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1
LOPES, HELENA RODRIGUES, ALBA LUCIA SOLINO NOLETO, MARC DIAZ de LAS HERAS, and MERLIN S. BERGDOLL. "Selective Enterotoxin Production in Foods by Staphylococcus aureus Strains That Produce More Than One Enterotoxin." Journal of Food Protection 56, no. 6 (June 1, 1993): 538–40. http://dx.doi.org/10.4315/0362-028x-56.6.538.
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Staphylococcus aureus strain S-6, producer of enterotoxins A and B; strain FRI-913, producer of enterotoxins A, C, and E; and strain FRI-196E, producer of enterotoxins A and D, were grown in milk (pH 6.8), potato salad with mayonnaise, and boiled egg white (pH 8.0–8.5). Enterotoxins were detectable in milk incubated at 26°C when colony counts were less than 106. Enterotoxin production by strain S-6 was detectable in potato salad at 106 CFU at both 26 and 37°C. Enterotoxin A production by strain FRI-913 was detectable at approximately 106 CFU/g, whereas enterotoxin C was detectable only when growth reached approximately 108 CFU/g. Production of enterotoxins A and D by strain FRI-196E was detectable when growth was greater than 107 CFU/g. Production of enterotoxins A and B by strain S-6 in boiled egg white was detectable at greater than 106 CFU/g. In most experiments, enterotoxins A and C from strain FRI-913 were detectable when cell counts were greater than 107 CFU/g, whereas enterotoxin A and enterotoxin D production by strain FRI-196E was detectable at counts between 105 and 106 CFU/g. It can be concluded that enterotoxin production is influenced by the time of incubation and the composition and pH of the food.
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Chopra, A. K., and C. W. Houston. "Purification and partial characterization of a cytotonic enterotoxin produced by Aeromonas hydrophila." Canadian Journal of Microbiology 35, no. 7 (July 1, 1989): 719–27. http://dx.doi.org/10.1139/m89-117.
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This report describes the purification and partial characterization of a cytotonic enterotoxin produced by a human diarrheal isolate (SSU) of Aeromonas hydrophila. The extracellular enterotoxin was purified by (NH4)2SO4 precipitation, hydrophobic column chromatography, and chromatofocusing. The highly purified enterotoxin exhibited a molecular mass of 44 kDa and an isoelectric point in the range of 4.3–5.5 as determined by chromatofocusing. Western blot analysis using Aeromonas anti-enterotoxin revealed a single band at 44 kDa; however, cholera antitoxin failed to detect the enterotoxin antigen. This non-cholera toxin cross-reactive (non-CTC) enterotoxin was biologically active in vivo as determined by rabbit ligated ileal loop and rabbit skin vascular permeability assays. Biological activity also was expressed in vitro by this toxin as measured by the elongation of Chinese hamster ovary (CHO) cells. The enterotoxic activity associated with this molecule was neutralized completely by homologous antibodies but not by cholera antitoxin. The purified toxin preparation was free of hemolytic and cytotoxic activities as determined by its inability to lyse rabbit red blood cells or damage CHO cells, respectively. Furthermore, this toxin induced the elevation of cAMP in CHO cells suggesting thereby that the mechanism of action of Aeromonas non-CTC enterotoxin may be similar to heat-labile enterotoxins of Escherichia coli and Vibrio cholerae.Key words: Aeromonas hydrophila, cytotonic enterotoxin, cholera toxin, cAMP
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CENCI-GOGA, B. T., M. KARAMA, P. V. ROSSITTO, R. A. MORGANTE, and J. S. CULLOR. "Enterotoxin Production by Staphylococcus aureus Isolated from Mastitic Cows." Journal of Food Protection 66, no. 9 (September 1, 2003): 1693–96. http://dx.doi.org/10.4315/0362-028x-66.9.1693.
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Staphylococcus aureus is an important cause of mastitis in cows. The ability of S. aureus strains to produce one or more enterotoxins in milk and dairy products is linked to staphylococcal food poisoning. To determine whether staphylococci causing bovine mastitis could cause human foodborne intoxication, the production of staphylococcal enterotoxins A through D (SEA, SEB, SEC, and SED) by 160 S. aureus isolates was evaluated with the use of a reverse passive latex agglutination enterotoxin kit. All S. aureus strains were isolated over a 9-month period from 2,343 routine submissions of a composite quarter collection of individual mastitic cows at 18 dairy farms in the San Joaquin Valley in California. Prior to enterotoxin detection, isolates were grown by a method that enhances the in vitro synthesis of enterotoxin. Twenty-two of 160 S. aureus isolates produced enterotoxin. Seven produced SEC, 12 produced SED, and 3 produced both SEC and SED. None of the isolates produced SEA or SEB.
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Valihrach, L., K. Demnerová, R. Karpíšková, and I. Melenová. "The expression of selected genes encoding enterotoxins in Staphylococcus aureus strains." Czech Journal of Food Sciences 27, Special Issue 2 (January 3, 2010): 56–65. http://dx.doi.org/10.17221/208/2009-cjfs.
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Staphylococcus aureus is an important food-borne pathogen, which produces many toxic substances that cause a variety of illnesses. Some strains of S. aureus produce thermostable enterotoxins that can be responsible for alimentary intoxication. The aim of this work was to establish a protocol for the study of 9 enterotoxin genes expression (sea-sej). First, a method for the detection of genes encoding enterotoxins was established and then a method for the determination of the expression of these genes was optimised, using a range of the PCR techniques (multiplex, touchdown and real-time). The expression of staphylococcal enterotoxin genes was evaluated both qualitatively and quantitatively. In present study were used S. aureus strains from culture collections as well as those newly-isolated from raw milk samples. The obtained results indicate the various expression of the different genes for enterotoxin. However the main benefit of this work is the established protocol for the study of enterotoxin gene expression, which can provide a better understanding of the conditions for the enterotoxins production.
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Thomas, Damien, Olivier Dauwalder, Virginie Brun, Cedric Badiou, Tristan Ferry, Jerome Etienne, François Vandenesch, and Gerard Lina. "Staphylococcus aureus Superantigens Elicit Redundant and Extensive Human Vβ Patterns." Infection and Immunity 77, no. 5 (March 2, 2009): 2043–50. http://dx.doi.org/10.1128/iai.01388-08.
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ABSTRACT Staphylococcus aureus can produce a wide variety of exotoxins, including toxic shock syndrome toxin 1 (TSST-1), staphylococcal enterotoxins, and staphylococcal enterotoxin-like toxins. These toxins share superantigenic activity. To investigate the β chain (Vβ) specificities of each of these toxins, TSST-1 and all known S. aureus enterotoxins and enterotoxin-like toxins were produced as recombinant proteins and tested for their ability to induce the selective in vitro expansion of human T cells bearing particular Vβ T-cell receptors (TCR). Although redundancies were observed between the toxins and the Vβ populations, each toxin induced the expansion of distinct Vβ subsets, including enterotoxin H and enterotoxin-like toxin J. Surprisingly, the Vβ signatures were not associated with a specific phylogenic group of toxins. Interestingly, each human Vβ analyzed in this study was stimulated by at least one staphylococcal superantigen, suggesting that the bacterium derives a selective advantage from targeting the entire human TCR Vβ panel.
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Radoslava, Savić Radovanović, Zdravković Nemanja, and Velebit Branko. "Occurrence and Characterization of Enterotoxigenic Staphylococci Isolated from Soft Cheeses in Serbia." Acta Veterinaria 70, no. 2 (June 1, 2020): 238–54. http://dx.doi.org/10.2478/acve-2020-0017.
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AbstractA total of 415 cheese samples produced with raw or cooked milk collected from local markets were analysed for the presence of coagulase-positive staphylococci. In 85 (20.48%) samples the presence of coagulase positive staphylococci was detected. The ELFA technique VIDAS SET2 (BioMerieux, France) was used for testing coagulase-positive staphylococci strains to produce classical enterotoxins (SEA, SEB, SEC, SED, SEE), and to determine the enterotoxins in cheese samples. The number of coagulase-positive staphylococci in cheese samples ranged from 1-5.79 log CFU g-1. Out of 85 coagulase-positive strains 26 (30.59%) produced enterotoxins. The presence of genes for the synthesis of staphylococcal enterotoxins (SE) in the obtained extracts of DNA from 26 enterotoxigenic strains was detected by conventional multiplex PCR technique (for genes sea and seb) i.e. the Real-Time PCR technique for genes sec, sed and see. In all 26 strains of coagulase-positive staphylococci (originating from cheeses produced from raw or cooked milk, which were enterotoxin producers) sea was present, and in 24 strains in addition to sea gene, seb was detected. None of the isolates possessed genes for the synthesis of enterotoxin C (SEC), D (SED) and E (SEE). Out of 26 tested cheese samples positive for enterotoxigenic coagulase-positive staphylococci, enterotoxin was detected in 2 (7.69%) samples of sweet-coagulating cheese, in which the number of enterotoxigenic coagulase-positive staphylococci exceeded 5 log CFU g-1. In sweet-coagulating cheeses in which the number of coagulase-positive staphylococci exceeds 5 log CFU g-1 and the pH value was higher than 5.0, enterotoxins may be present in amounts sufficient to cause intoxication.
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Al Bustan, M. A., E. E. Udo, and T. D. Chugh. "Nasal carriage of enterotoxin-producingStaphylococcus aureusamong restaurant workers in Kuwait City." Epidemiology and Infection 116, no. 3 (June 1996): 319–22. http://dx.doi.org/10.1017/s0950268800052638.
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SUMMARYEnterotoxin-producingStaphylococcus aureusis a common cause of staphylococcal food poisoning. To determine the incidence of carriage of enterotoxin-producingS. aureusin a sample of the healthy population in Kuwait city, restaurant workers in the city were screened for nasal carriage ofS. aureus. 26·6% of 500 workers studied carriedS. aureusand 86·6% of theS. aureusproduced staphylococcal enterotoxins. 28 % produced enterotoxin A, 28·5 % produced enterotoxin B, 16·4% produced enterotoxin C and 3·5% produced enterotoxin D. Ten isolates produced both enterotoxins A and B or A and C. 73 % of the isolates were untypeable with standard phages. However, 17·1%, 3% and 6% belonged to phage groups I, II and III respectively. The results demonstrated a high level of enterotoxigenicS. aureuscarriage among restaurant workers which although lower than that reported for the general population and hospital workers may be important in the restaurant industry.
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Melconian, A. K., J. Fleurette, and Y. Brun. "Studies on staphylococci from toxic shock syndrome in France, 1981–1983." Journal of Hygiene 94, no. 1 (February 1985): 23–29. http://dx.doi.org/10.1017/s002217240006109x.
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SUMMARYStaphylococci from 22 cases of toxic shock syndrome with onsets between 1981 and March 1983 have been studied. Another four cases were detected by abstract surveillance. Three of these patients died. The case histories show that the syndrome occurs in women during menstruation as well as in males and in children, and is associated withStaphylococcus aureusinfections.The production of enterotoxins (A, B, C) and toxic shock toxin byS. aureusisolates from toxic shock syndrome was investigated. Twenty-two of the 23 isolates were found to be toxigenie: 7 produced enterotoxin A, 8 produced enterotoxin B, 3 produced enterotoxin C and 13 produced toxic shock toxin. The latter was found with enterotoxin A in five cases, and with enterotoxins A and B in only one case.Sixty-three percent of 40S. aureusstrains isolated from the vagina of patients with diseases other than toxic shock syndrome produced toxin; eight of these strains produced toxic shock toxin.
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KIM, JUNG-BEOM, JAI-MOUNG KIM, SO-YEONG KIM, JONG-HYUN KIM, YONG-BAE PARK, NA-JUNG CHOI, and DEOG-HWAN OH. "Comparison of Enterotoxin Production and Phenotypic Characteristics between Emetic and Enterotoxic Bacillus cereus." Journal of Food Protection 73, no. 7 (July 1, 2010): 1219–24. http://dx.doi.org/10.4315/0362-028x-73.7.1219.
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Bacillus cereus was divided into emetic toxin (cereulide)– and enterotoxin-producing strains, but emetic toxin–producing B. cereus is difficult to detect immunochemically. Screening methods for emetic toxin–producing B. cereus are needed. The objectives of this study were to identify and detect emetic toxin–producing B. cereus among 160 B. cereus strains, and to compare enterotoxin production and phenotypic characteristics between the emetic toxin–producing and enterotoxin-producing strains. Forty emetic toxin–producing B. cereus strains were determined with high-pressure liquid chromatography–mass spectrometry analysis. Among the emetic toxin–producing strains (n = 40), 31 (77.5%) and 3 (7.5%) strains produced nonhemolytic enterotoxin (NHE) and hemolysin BL (HBL) enterotoxins, respectively. In addition, 107 (89.2%) and 100 (83.3%) strains produced NHE and HBL enterotoxins among the enterotoxin-producing strains (n = 120). The number of strains positive for starch hydrolysis, salicin fermentation, and hemolysis among the emetic toxin–producing strains were 3 (7.5%), 3 (7.5%), and 26 (65.0%), respectively, and among enterotoxin-producing strains, these numbers were 101 (84.2%), 100 (83.3%), and 111 (92.5%), respectively. In particular, the three emetic toxin–producing B. cereus strains (JNHE 6, JNHE 36, and KNIH 28) produced the HBL and NHE enterotoxins and were capable of starch hydrolysis and salicin fermentation. The absence of HBL enterotoxin and certain phenotypic properties, such as starch hydrolysis and salicin fermentation, indicates that these properties were not critical characteristics of the emetic toxin–producing B. cereus tested in this study.
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MANTIS (Α.Ι. ΜΑΝΤΗΣ), A. J., and D. K. PAPAGEORGIOU (Δ.Κ. ΠΑΠΑΓΕΩΡΓΙΟΥ). "Conditions of staphylococcal enterotoxin production in milk and milk products." Journal of the Hellenic Veterinary Medical Society 54, no. 3 (December 19, 2017): 242. http://dx.doi.org/10.12681/jhvms.15267.
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The authors reviewed the existing scientific data, concerning the ability of Staphylococcus aureus to grow and produce enterotoxins in milk and in dairy products particularly in cheeses. S. aureus can grow well in liquid raw or pasteurized milks and produce enterotoxins if the product is stored in favorable for the pathogen temperature. Cream also supports growth of S. aureus and enterotoxin production, but butter as well as fermented products like yogurt and buttermilk are not favorable substrates for the production of enterotoxins. Cheeses represent a complex environment, due to their great variety in processing technology and environment. Fresh cheeses, soft cheeses and semi-hard and hard cheeses can support growth of S. aureus during the first stages of production up to 48 hours. Normally, the pathogen, if it is present in the milk, will multiply for 3-4 logs and after that, when acidity develops, the populations of S. aureus decrease and usually disappear by the end of the ripening period. However, if enterotoxins are produced during the multiplication phase of the pathogen, it will remain active in the cheese for a long time. Internal mould ripened cheeses (e.g. blue cheese), pasta filata cheeses or the processed cheeses do not represent favorable substrates for the multiplication of S. aureus and enterotoxin production. On the contrary, whey cheeses form a very favorable environment for the enterotoxins' production, because of their high pH and the absence of antagonistic bacterial flora.
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Bergdoll, Merlin S. "Staphylococcus aureus." Journal of AOAC INTERNATIONAL 74, no. 4 (July 1, 1991): 706–10. http://dx.doi.org/10.1093/jaoac/74.4.706.
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Abstract The analytical methods for the detection of the staphylococcal enterotoxins can be divided into 2 categories: (1) methods for detection of enterotoxin-producing staphylococcal strains; (2) methods for detection of enterotoxin in foods. Gel diffusion methods (Ouchterlony, microslide), in which the enterotoxin produced by any given strain is compared to one of the identified enterotoxins, are used most frequently for strain testing. The sensitivity of these methods is from 0.1 to 0.5 μg enterotoxin/mL, which is normally adequate to determine the enterotoxigenicity of strains. The methods for the detection of enterotoxin in foods need to be much more sensitive to detect less than 1 ng of enterotoxin/g of food that may be present. The radioimmunoassay (RIA), the enzymelinked immunosorbent assay (ELISA), and the reversed passive latex agglutination (RPLA) method have the necessary sensitivity to detect 1 ng/g of enterotoxin in foods without the use of complicated extraction-concentration procedures. Kits based on the ELISA and RPLA methods are now available commercially for the detection of enterotoxins in foods. Tests have shown that the ELISA methods are somewhat more sensitive than the RPLA method.
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Pajić, Marija, Stanko Boboš, Branko Velebit, Zoran Rašić, Vera Katić, Miodrag Radinović, Aleksandra Nikolić, Dušan Simonović, and Milijana Babić. "Prevalence and Molecular Characterization of Enterotoxin-Producing Strains of Staphylococcus Aureus Isolated from Serbian Dairy Cows." Acta Veterinaria 66, no. 4 (December 1, 2016): 466–77. http://dx.doi.org/10.1515/acve-2016-0040.
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AbstractStaphylococcus aureus is known worldwide as a frequent cause of mastitis in dairy cattle. Due to the production of heath resistant enterotoxins, this pathogen is also a major cause of food poisoning among humans, with symptoms of often severe vomiting and diarrhea. The aim of our study was to determine the prevalence of enterotoxinproducing strains of S. aureus originating from samples of cows with subclinical and clinical mastitis in the Republic of Serbia. Furthermore, we analyzed the type of staphylococcal enterotoxin they produce and phylogenetic relatedness among the S. aureus isolates recovered from milk in this study. Production of staphylococcal enterotoxins A, B, C, D and E was determined by commercial immunoenzyme assay VIDAS® SET2, and presence of corresponding genes encoding enterotoxin synthesis in positive isolates confi rmed by Polymerase Chain Reaction. Enterotoxin production was determined in 5 out of 75 (6.67%) isolates of S. aureus and all of them produced staphylococcal enterotoxins C. After analyzing the nucleotide sequence of the gene encoding the synthesis of staphylococcal protein A, S. aureus isolates were assigned into 2 phylogenetic groups, including 7 clusters. All S. aureus isolates with the presence of sec gene formed one cluster even dough they originated from milk samples from different farms.
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STELMA, GERARD N., RONALD G. CRAWFORD, PROCTER L. SPAULDING, and ROBERT M. TWEDT. "Evidence That Clostridium perfringens Produces Only One Enterotoxin." Journal of Food Protection 48, no. 3 (March 1, 1985): 232–33. http://dx.doi.org/10.4315/0362-028x-48.3.232.
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Thirteen Clostridium perfringens isolates classified as nonenterotoxigenic by radioimmunoassay (RIA) were tested for biological activity in rabbit ileal loops to determine whether these organisms produced enterotoxins serologically unrelated to the classical C. perfringens enterotoxin. None of these strains was active in the ileal loop assays. The large number of RIA-negative isolates obtained from food-poisoning outbreaks is more likely due to the failure to isolate causative strains rather than to the existence of novel enterotoxins.
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SU, YI-CHENG, and AMY C. LEE WONG. "Detection of Staphylococcal Enterotoxin H by an Enzyme-Linked Immunosorbent Assay." Journal of Food Protection 59, no. 3 (March 1, 1996): 327–30. http://dx.doi.org/10.4315/0362-028x-59.3.327.
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A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the detection of a newly identified staphylococcal enterotoxin H (SEH). Peroxidase was conjugated to antibodies specific to the enterotoxin. 2,2′ Azino-bis(3-ethylbenz-thiazoline-6-sulfonic acid)(ABTS) in hydrogen peroxide solution was used as the enzyme substrate. A standard curve of purified SEH was prepared with concentrations ranging from 1.3 to 50 ng/ml. SEH at levels equal to 2.5 ng/ml and higher were detected by this procedure. Culture supernatant from the growth of selected Staphylococcus aureus strains was analyzed by using the ELISA. SEH was produced by three of 20 strains that produced one identified enterotoxin. Ten of 21 strains, previously shown to produce substances that induced emesis in monkeys but not any known enterotoxins (A through E), were also positive for SEH production. The other 11 strains gave negative results in the ELISA, indicating that other unidentified serological types of enterotoxin exist.
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Necidová, Lenka, Šárka Bursová, Alena Skočková, Bohdana Janštová, Pavla Prachařová, Žaneta Ševčíková, and Bohumíra Janštová. "Growth and enterotoxin production of Bacillus cereus in cow, goat, and sheep milk." Acta Veterinaria Brno 83, no. 10 (2014): S3—S8. http://dx.doi.org/10.2754/avb201483s10s3.
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The aim of this study was to compare Bacillus cereus growth rates and diarrhoeal enterotoxin production in raw and pasteurized goat, sheep, and cow milk in terms of storage conditions. Milk samples were inoculated with B. cereus (CCM 2010), which produces diarrhoeal enterotoxins. Enterotoxin production was tested by ELISA (Enzyme-Linked Immunosorbent Assay), and the count of B. cereus was determined by the plate method. With raw cow milk, B. cereus growth and enterotoxin production can be completely suppressed; in raw goat and sheep milk, enterotoxin was produced at 22 °C. In pasteurized cow, goat, and sheep milk, the B. cereus count increased under all storage conditions, with more rapid growth being observed at 15 °C (sheep milk) and 22 °C (cow and goat milk). Enterotoxin presence was detected at 15 °C and 22 °C, and with pasteurized cow milk also at 8 °C. Our model experiments have determined that B. cereus multiplication and subsequent enterotoxin production depend on storage temperature and milk type.
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Mohammed, Srwa A., Mohammed I. J. Al-ani, Dereh L. Mohammed, Lina R. Salar, and Banaz M. Rasul. "Inhibition of Staphylococcus aureus enterotoxin genes by using plant extracts." Innovaciencia Facultad de Ciencias Exactas Físicas y Naturales 6, no. 2 (December 28, 2018): 1–8. http://dx.doi.org/10.15649/2346075x.469.
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Introduction: Enterotoxigenic Staphylococcus aureus is an important pathogen that causes septicemia and bacteremia and is often associated with serious complications, such as endocarditis and osteomyelitis. Some Staphylococcus enterotoxins require only minute quantities to be toxic in humans. The present study focused on investigation how to remove this problematic issue. Objectives: This study was conducted to inhibit S. aureus enterotoxin genes that obtained from positive blood culture bottles of patients at the pediatric hospital in Sulaimania city. Methods: Twenty five isolates of S. aureus were isolated among 100 positive blood culture bottles and determined the strains that produce enterotoxins through culture method. Then, the enterotoxin genes that located on plasmids were cured by two medicinal plants (Eugenia caryophyllata and Cinnamomum zeylanicum). Results: The results showed that nine out of 25 isolates were released enterotoxins from which the plasmid encoding enterotoxin genes were confirmed in four of them. And, two of the isolates were transferred to recipient DH10B E. coli isolate successfully. Methanol extracts of (E. caryophyllata and C. zeylanicum) were used at sub minimum inhibition concentration as curing agents. Conclusion: Methanol extracts of (E. caryophyllata and C. zeylanicum) have grate effect on eliminating the plasmidsencoding enterotoxin gene of S. aureus.
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SU, YI-CHENG, and AMY C. L. WONG. "Optimal Condition for the Production of Unidentified Staphylococcal Enterotoxins." Journal of Food Protection 56, no. 4 (April 1, 1993): 313–16. http://dx.doi.org/10.4315/0362-028x-56.4.313.
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The sac culture method in combination with 6% NZ-Amine A plus 1% yeast extract was found to be the optimal condition for staphylococcal enterotoxins A (SEA) and D (SED) production. This growth condition was tested for the production of unidentified staphylococcal enterotoxins (SEs). Twenty-one Staphylococcus aureus strains that previously showed an emetic response in monkeys but were negative for any of the identified SEs when cultured by the membrane-over-agar method were grown by the sac culture method. All 21 strains produced at least one known SE. One strain produced only enterotoxin C (SEC). Nine strains produced only SED. One strain produced both SEA and SED. Four produced both SEC and SED. One produced SEA, enterotoxin B (SEB), and SED. Two produced SEA, SEC, and SED. Three produced SEA, SEB, SEC, and SED. One of these strains, FRI-569, that produced only SED at a low level (10 ng/ml) was selected to confirm the production of an unidentified SE by the monkey feeding test. Emesis was induced in five out of six monkeys. The total amount of SED in the supernatant fluids fed to monkeys was only 0.5 μg, or 2.5% of the 50% emetic dose (20 μg). Production of an unidentified SE by strain FRI-569 was therefore confirmed. This optimal condition can be used to produce increased amounts of unidentified SEs for purification.
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BENNETT, REGINALD W. "Staphylococcal Enterotoxin and Its Rapid Identification in Foods by Enzyme-Linked Immunosorbent Assay–Based Methodology." Journal of Food Protection 68, no. 6 (June 1, 2005): 1264–70. http://dx.doi.org/10.4315/0362-028x-68.6.1264.
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The problem of Staphylococcus aureus and other species as contaminants in the food supply remains significant on a global level. Time and temperature abuse of a food product contaminated with enterotoxigenic staphylococci can result in formation of enterotoxin, which can produce foodborne illness when the product is ingested. Between 100 and 200 ng of enterotoxin can cause symptoms consistent with staphylococcal intoxication. Although humans are the primary reservoirs of contamination, animals, air, dust, and food contact surfaces can serve as vehicles in the transfer of this pathogen to the food supply. Foods may become contaminated during production or processing and in homes or food establishments, where the organism can proliferate to high concentrations and subsequently produce enterotoxin. The staphylococcal enterotoxins are highly heat stable and can remain biologically active after exposure to retort temperatures. Prior to the development of serological methods for the identification of enterotoxin, monkeys (gastric intubation) and later kittens (intravenous injection) were used in assays for toxin detection. When enterotoxins were identified as mature proteins that were antigenic, serological assays were developed for use in the laboratory analysis of foods suspected of containing preformed enterotoxin. More recently developed methods are tracer-labeled immunoassays. Of these methods, the enzyme-linked immunosorbent assays are highly specific, highly sensitive, and rapid for the detection of enterotoxin in foods.
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Lampugnani, Camila, Maike Taís Maziero Montanhini, Maria Emilene Martino Campos‐Galvão, Luis Augusto Nero, and Luciano dos Santos Bersot. "Enterotoxins production, biofilm formation and antimicrobial resistance of Staphylococcus aureus strains isolated from refrigerated raw cow milk." Acta Scientiarum. Technology 42 (November 29, 2019): e45231. http://dx.doi.org/10.4025/actascitechnol.v42i1.45231.
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This study aimed to isolate Staphylococcus aureus in refrigerated raw cow milk, and identify the presence of enterotoxin-expression genes, enterotoxin production and adherence ability, and antimicrobial resistance potential of the isolated strains. Fifty raw milk samples obtained in different dairy farms were analyzed for S. aureus and evaluated in the isolates the presence of genes associated with the production of major staphylococcal enterotoxins and biofilm formation. In vitro assays were also performed to evaluate the production of enterotoxins and adherence ability, and the antimicrobial resistance. One half (25/50) of raw milk samples presented coagulase-positive staphylococci and 95.2% of the isolates were confirmed to be S. aureus. Among them, 42.4% were carrying genes for enterotoxins production; however, only one isolate was able to produce enterotoxins. All S. aureus isolates were carrying at least two genes associated with biofilm formation and 95.2% isolates was able to adhere upon the in vitro assay. All isolates demonstrated antimicrobial resistance potential to one or more of the tested antibiotics.
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SOKARI, TOKUBIYE G., and SAUL O. ANOZIE. "Occurrence of Enterotoxin Producing Strains of Staphylococcus aureus in Meat and Related Samples from Traditional Markets in Nigeria." Journal of Food Protection 53, no. 12 (December 1, 1990): 1069–70. http://dx.doi.org/10.4315/0362-028x-53.12.1069.
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Coagulase-positive Staphylococcus aureus were isolated from 449 (84.7%) of 530 meat and related samples obtained from traditional markets in Nigeria. All 100 fresh beef and associated 40 wash water and 40 drip water samples examined yielded coagulase-positive S. aureus compared with 258 (86%) of 300 Suya and 61 (61%) of 100 fried beef samples. Of the 449 coagulase-positive strains of S. aureus, 243 (54.1%) elaborated various enterotoxins. Suya (condiment - coated thin slices of skewered beef roasted over wood or charcoal flame) and fried beef yielded the highest proportions of enterotoxin producing strains of 59.3% and 58%, respectively. Relatively lower proportions of strains from fresh beef (52%) and water associated with fresh beef (45%) produced enterotoxin. Most of the organisms tested (139/57.2%) synthesized enterotoxin A (SEA). A few, 37 (15.2%), produced enterotoxin B (SEB), with fewer still producing enterotoxins D (SED, 6.2%) and C (SEC, 5.3%). It is suggested that the high level of contamination with S. aureus of the samples examined resulted from cross contamination, reflecting excessive hand contact with the foodstuffs.
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Korpysa-Dzirba, Weronika, and Jacek Osek. "Detection of classical genes and enterotoxins of Staphylococcus aureus isolated from raw milk in the south-east region of Poland." Bulletin of the Veterinary Institute in Pulawy 58, no. 4 (December 1, 2014): 559–61. http://dx.doi.org/10.2478/bvip-2014-0086.
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Abstract The aim of the study was to investigate if the enterotoxigenic strains of S. aureus isolated from raw milk are able to produce staphylococcal enterotoxins (SEs) A - E. A total of 168 of S. aureus isolates from raw milk collected in the south - east region of Poland (Lubelskie Province) were tested for SE production by the ELFA, while multiplex PCR was applied for detection of enterotoxin genes (sea, seb, sec, sed, see). It was found that 20 (11.9%) out of 168 strains were positive for one or more classical SE markers and 19 of them produced a detectable level of enterotoxins. The results obtained by mPCR and ELFA were in agreement, when the presence of A, B, and D toxin types was tested; whereas SEC was not found by the ELFA although the S. aureus was positive for the respective gene. The results of the two methods showed that mPCR identified one more strain potentially producing enterotoxin than the ELFA, which may suggest that the enterotoxigenic S. aureus are not always able to express the toxin protein.
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Beckers, H. J., F. M. van Leusden, and P. D. Tips. "Growth and enterotoxin production ofStaphylococcus aureusin shrimp." Journal of Hygiene 95, no. 3 (December 1985): 685–93. http://dx.doi.org/10.1017/s0022172400060794.
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SUMMARYStrains ofStaphylococcus aureusisolated from shrimp were examined for phage pattern and enterotoxin production; 63% of the strains isolated from North Sea shrimp were typable with the International and additional set of phages, as were 38% of the strains isolated from South-East Asian shrimp. Staphylococcal enterotoxin(s) (SE) were produced by 48% and 35% of strains isolated from North Sea and South-East Asian shrimp respectively. Growth and enterotoxin production byS. aureusin shrimp was examined in storage experiments at 22 °C.S. aureusincreased by 1–2 log units in 24 h when the organism was only a minor part of the total microflora of shrimp. WhenS. aureuswas an equivalent part of the total flora its numbers increased by 3–4 log units in 24 h. Enterotoxins A and B became detectable when the number ofS. aureusexceeded 107per g in aseptically peeled shrimp. Results indicate thatS. aureusis able to produce enterotoxin in shrimp, but its production depends upon a number of factors, including the relationship betweenS. aureusand competitive micro-organisms. It is concluded that the presence ofS. aureuson commercially produced shrimp represents a potential hazard to health.
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Piechota, M., B. Kot, E. Zdunek, J. Mitrus, J. Wicha, and M. K. Wolska. "Distribution of classical enterotoxin genes in staphylococci from milk of cows withand without mastitis and the cowshed environment." Polish Journal of Veterinary Sciences 17, no. 3 (September 1, 2014): 407–11. http://dx.doi.org/10.2478/pjvs-2014-0058.
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AbstractThe aim of this study was to analyze by PCR 185 isolates of Staphylococcus from milk of cows with- and without mastitis and from the cowsheds environment for their potential ability to produce five classical staphylococcal enterotoxins. Among S. aureus isolates 8 (32%) carried enterotoxin genes and only 2 of them had more than one gene. The enterotoxin genes were detected in 22 (13.7%) coagulase-negative staphylococci (CNS) isolates, among them in 9 (11.4%) isolates of S. xylosus, 5 (16.7%) S. sciuri, 3 (10.3%) S. epidermidis and in 5 (22.7%) Staphylococcus spp. In some CNS 2 or 3 genes were detected simultaneously. Among the investigated enterotoxin genes, sec was the most prevalent (70%). The genes encoding enterotoxin B and D were detected in 5 (16.7%) and 6 (20%) isolates, respectively. The lowest number of isolates had sea and see genes.The genes encoding enterotoxins were often identified in staphylococci from milk of cows with mastitis (73.4% of detected genes), while only 6 (20%) isolates from milk of cows without mastitis and 2 (6.6%) isolates from cowshed environment were positive for enterotoxin genes.The results showed that CNS from bovine milk, like S. aureus, carried enterotoxin genes and may pose a risk for public health.
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Jarraud, Sophie, Grégoire Cozon, François Vandenesch, Michèle Bes, Jerome Etienne, and Gerard Lina. "Involvement of Enterotoxins G and I in Staphylococcal Toxic Shock Syndrome and Staphylococcal Scarlet Fever." Journal of Clinical Microbiology 37, no. 8 (1999): 2446–49. http://dx.doi.org/10.1128/jcm.37.8.2446-2449.1999.
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We investigated the involvement of the recently described staphylococcal enterotoxins G and I in toxic shock syndrome. We reexamined Staphylococcus aureus strains isolated from patients with menstrual and nonmenstrual toxic shock syndrome (nine cases) or staphylococcal scarlet fever (three cases). These strains were selected because they produced none of the toxins known to be involved in these syndromes (toxic shock syndrome toxin 1 and enterotoxins A, B, C, and D), enterotoxin E or H, or exfoliative toxin A or B, despite the fact that superantigenic toxins were detected in a CD69-specific flow cytometry assay measuring T-cell activation. Sets of primers specific to the enterotoxin G and I genes (seg andsei, respectively) were designed and used for PCR amplification. All of the strains were positive for seg andsei. Sequence analysis confirmed that the PCR products, corresponded to the target genes. We suggest that staphylococcal enterotoxins G and I may be capable of causing human staphylococcal toxic shock syndrome and staphylococcal scarlet fever.
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SCHUBERT, JUSTYNA, SYLWIA KRAKOWIAK, and JACEK BANIA. "Production of staphylococcal enterotoxins in food." Medycyna Weterynaryjna 74, no. 1 (2018): 16–22. http://dx.doi.org/10.21521/mw.5837.
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Staphylococcal food poisoning results from ingestion of food contaminated with toxins produced by enterotoxigenic Staphylococcus aureus strains. Common symptoms of this intoxication include vomiting, diarrhea, and abdominal cramps. Staphylococcal enterotoxins are resistant to heat and a number of environmental factors. Certain cheeses, milk powder, and whey powder are the only foodstuffs that are being routinely examined for the presence of staphylococcal enterotoxins SEA-SEE. The newly identified enterotoxins are not included in the current examination scheme. Enterotoxin-producing staphylococci were already isolated from meat, meat products, milk, dairy products, fermented food products, vegetables, pastries and fish products. It has been demonstrated that many environmental factors associated with food processing and storage can significantly influence the level of secreted enterotoxins by S. aureus strains. Nevertheless, only a few studies on the production of staphylococcal enterotoxins were conducted in foodstuffs. Most data on their expression is based on experiments performed with a low number of S. aureus strains, and usually only SEA-SEE enterotoxins are investigated. These results inclined many authors to the conclusion that milk and dairy products are unfavorable environments for expression of staphylococcal enterotoxins. However, recent research has indicated a significant heterogeneity in the ability of enterotoxin production in milk among S. aureus strains derived from diverse sources. S. aureus strains able to secrete high levels of enterotoxins in milk and meat juice were described. This research indicates that a high number of S. aureus strains should be used for studying staphylococcal enterotoxins expression in food. It seems to be the appropriate way to assess the risk of staphylococcal food poisoning....
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Rowan, Neil J., George Caldow, Curtis G. Gemmell, and Iain S. Hunter. "Production of Diarrheal Enterotoxins and Other Potential Virulence Factors by Veterinary Isolates of Bacillus Species Associated with Nongastrointestinal Infections." Applied and Environmental Microbiology 69, no. 4 (April 2003): 2372–76. http://dx.doi.org/10.1128/aem.69.4.2372-2376.2003.
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ABSTRACT With the exceptions of Bacillus cereus and Bacillus anthracis, Bacillus species are generally perceived to be inconsequential. However, the relevance of other Bacillus species as food poisoning organisms and etiological agents in nongastrointestinal infections is being increasingly recognized. Eleven Bacillus species isolated from veterinary samples associated with severe nongastrointestinal infections were assessed for the presence and expression of diarrheagenic enterotoxins and other potential virulence factors. PCR studies revealed the presence of DNA sequences encoding hemolysin BL (HBL) enterotoxin complex and B. cereus enterotoxin T (BceT) in five B. cereus strains and in Bacillus coagulans NB11. Enterotoxin HBL was also harbored by Bacillus polymyxa NB6. After 18 h of growth in brain heart infusion broth, all seven Bacillus isolates carrying genes encoding enterotoxin HBL produced this toxin. Cell-free supernatant fluids from all 11 Bacillus isolates demonstrated cytotoxicity toward human HEp-2 cells; only one Bacillus licheniformis strain adhered to this test cell line, and none of the Bacillus isolates were invasive. This study constitutes the first demonstration that Bacillus spp. associated with serious nongastrointestinal infections in animals may harbor and express diarrheagenic enterotoxins traditionally linked to toxigenic B. cereus.
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Seyoum, Eyasu Tigabu, Tesfu Kassa Mekonene, Daniel Asrat Woldetsadik, Bayleyegn Molla Zewudie, and Wondwossen Abebe Gebreyes. "Enterotoxin gene profile of Staphylococcus aureus isolates recovered from bovine milk produced in central Ethiopia." Journal of Infection in Developing Countries 10, no. 02 (February 28, 2016): 138–42. http://dx.doi.org/10.3855/jidc.6797.
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Introduction: Staphylococcal food intoxication is dependent on the production of enterotoxins, the single most important virulence factors. Various studies conducted in Ethiopia have depicted the prevalence of S. aureus in bovine milk. However, there is no published data regarding the enterotoxin gene profile of S. aureus isolates in Ethiopia. The aim of this study was, therefore, to evaluate enterotoxin gene carriage profile of S. aureus isolates recovered from bovine milk samples from central Ethiopia. Methodology: In this study, 109 S. aureus isolates recovered from bovine milk were analyzed for carriage of the classical enterotoxin genes. Genomic DNA extraction was performed using a commercially available kit. Two sets of multiplex polymerase chain reaction (PCR) assays were used to detect the five classical enterotoxin-coding genes and the toxic shock syndrome toxin gene. Results: At least one type of S. aureus enterotoxin gene (SE) was carried in 73 (66.9%) of the isolates. The most frequently encountered gene was sea (40; 36.7%) followed by seb (19; 17.4%), see (18; 16.5%), tst (16; 14.7%), sec-1 (12; 11.01%), and sed (7; 6.4%). Of the 73 S. aureus isolates harboring at least one of the enterotoxin genes, 26 (35.6%) strains harbored more than one enterotoxin gene. Conclusions: More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk specimens contaminated by S. aureus could have a high chance of causing food intoxication.
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HALPIN-DOHNALEK, MARGARET I., and ELMER H. MARTH. "Staphylococcus aureus: Production of Extracellular Compounds and Behavior in Foods - A Review." Journal of Food Protection 52, no. 4 (April 1, 1989): 267–82. http://dx.doi.org/10.4315/0362-028x-52.4.267.
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Growth of Staphylococcus aureus is accompanied by production of such extracellular compounds as hemolysins, nuclease, coagulase, lipase, and enterotoxins. Enterotoxins that can cause food poisoning are produced by about one-third of the coagulase-positive strains of S. aureus. The enterotoxins are a heterogeneous group of heat-stable, water-soluble, single-chain globular proteins having a molecular weight between 28,000 and 35,000 daltons. Production of enterotoxin by appropriate strains of S. aureus is affected by the nutritional quality and pH of the substrate, temperature, atmosphere, sodium chloride (and hence water activity), other chemicals, and competing microorganisms. Outbreaks of staphylococcal food poisoning most often are associated with processed red meats, poultry products (especially chicken salad), sauces, dairy products (especially cheeses), and custard- or cream-filled bakery products. Ham and associated products often are involved in as many as 30% of outbreaks of staphylococcal food poisoning. Most outbreaks result from the combined effects of contamination of the food, often through unsanitary handling, with S. aureus and holding the food at the wrong temperature thus allowing growth and synthesis of enterotoxin by the pathogen.
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Dietrich, Richard, Maximilian Moravek, Christine Bürk, Per Einar Granum, and Erwin Märtlbauer. "Production and Characterization of Antibodies against Each of the Three Subunits of the Bacillus cereus Nonhemolytic Enterotoxin Complex." Applied and Environmental Microbiology 71, no. 12 (December 2005): 8214–20. http://dx.doi.org/10.1128/aem.71.12.8214-8220.2005.
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ABSTRACT The nonhemolytic enterotoxin (Nhe) is one of the two three-component enterotoxins which are responsible for diarrheal food poisoning syndrome caused by Bacillus cereus. To facilitate the detection of this toxin, consisting of the subunits NheA, NheB, and NheC, a complete set of high-affinity antibodies against each of the three components was established and characterized. A rabbit antiserum specific for the C-terminal part (15 amino acids) of NheC was produced using a respective synthetic peptide coupled to a protein carrier for immunization. Using purified B. cereus exoprotein preparations as immunogens, one monoclonal antibody against NheA and several antibodies against NheB were obtained. No cross-reactivity with other proteins produced by different strains of B. cereus was observed. Antibodies against the NheB component were able to neutralize the cytotoxic activity (up to 98%) of Nhe. Based on indirect enzyme immunoassays, the antibodies developed in this study were successfully used in the characterization of the enterotoxic activity of several B. cereus strains. For the first time, it could be shown that strains carrying the nhe genes usually express the complete set of the three components, including NheC. However, the amount of toxin produced varies considerably between the different strains.
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BRYANT, RAYMOND G., JOSEPHINE JARVIS, and GERRY GUIBERT. "Selective Enterotoxin Production by a Staphylococcus aureus Strain Implicated in a Foodborne Outbreak." Journal of Food Protection 51, no. 2 (February 1, 1988): 130–31. http://dx.doi.org/10.4315/0362-028x-51.2.130.
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More than 80 of 230 participants (>34.7%) at a literary conference became ill with acute gastroenteritis 3 to 14 h after a catered meal. Attack rate data implicated cheese tortellini as the suspect food (p=0.0087). Selective plating of partially prepared and finished tortellini produced Staphylcoccus aureus counts of 6.0 × 107 and 1.0 × 106 CFU per gram, respectively. Enterotoxin, phage typing, antibiotic sensitivity testing, and other biotyping studies were applied to S. aureus isolates from the suspect food and the single food-handler involved. All isolates reacted identically by all criteria, and each isolate produced both type A and C staphylococcal enterotoxins. Type A enterotoxin (0.90 ug/100 g) alone was detected in samples of the suspect food. The production of type C enterotoxin by the outbreak strain was delayed approximately 4 h relative to production of enterotoxin A when grown in Heart Infusion broth (pH 5.5). This study serves as an example of selective enterotoxin production by S. aureus in suspect foods which can be misleading to outbreak investigators.
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LOPES, HELENA RODRIGUES, ALBA LUCIA SOLINO NOLETO, and MERLIN S. BERGDOLL. "Production of Staphylococcal Enterotoxins A, D, and E by Sac Culture." Journal of Food Protection 54, no. 8 (August 1, 1991): 650–52. http://dx.doi.org/10.4315/0362-028x-54.8.650.
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The use of the sac culture method for production of relatively large amounts of enterotoxins A (SEA), D (SED), and E (SEE) for use in purification of the enterotoxins was investigated. One-hundred milliliters of medium per sac, made from Union Carbide sausage casing, with a shaking speed of 150 rpm was chosen as the optimum condition for the enterotoxin production. Brain heart infusion (BHI) broth was the medium of choice for production of SEA by strain FRI-722, with over 100 μg/ml being produced. Strain 1151m produced 20 μg/ml of SED in BHI medium which was 10 times that produced in shake flasks. The production of SEE was best in the Biosate + yeast extract medium, with adequate amounts being produced for purification.
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GÓMEZ-LUCÍA, ESPERANZA, JOAQUÍN GOYACHE, JOSÉ A. ORDEN, ANA DOMÉNECH, F. JAVIER HERNÁNDEZ, JOSÉ A. RUIZ-SANTA-QUITERIA, and GUILLERMO SUÁREZ. "Influence of Temperature of Incubation on Staphylococcus aureus Growth and Enterotoxin Production in Homemade Mayonnaise." Journal of Food Protection 53, no. 5 (May 1, 1990): 386–90. http://dx.doi.org/10.4315/0362-028x-53.5.386.
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Homemade mayonnaise, in which pH had been adjusted to a range between 5.0 and 5.8 by the addition of vinegar, was inoculated with eight Staphylococcus aureus strains known to be enterotoxigenic. They were incubated for a maximum of 7 days at 22, 28, 37, and 44°C. Periodically, staphylococcal growth and pH were determined. Mayonnaise samples were examined on d 7 for the presence of enterotoxins A, B, C, and D. Staphylococcal growth was higher at 22°C (average log10 7.21 cfu/g), than at the other temperatures tested (log10 7.15, 6.77, and 5.93 cfu/g, respectively for 28, 37, and 44°C), suggesting a better growth in mayonnaise at low room temperature. Enterotoxin synthesis took place mainly at 28°C, as 33.3% of the total enterotoxins produced were detected at this temperature. However, some strains synthesized high amounts of enterotoxin even at 22°C.
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Dietrich, R., C. Fella, S. Strich, and E. Märtlbauer. "Production and Characterization of Monoclonal Antibodies against the Hemolysin BL Enterotoxin Complex Produced byBacillus cereus." Applied and Environmental Microbiology 65, no. 10 (October 1, 1999): 4470–74. http://dx.doi.org/10.1128/aem.65.10.4470-4474.1999.
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ABSTRACT A total of five hybridoma cell lines that produced monoclonal antibodies against the components of the hemolysin BL (HBL) enterotoxin complex and sphingomyelinase produced by Bacillus cereuswere established and characterized. Monoclonal antibody 2A3 was specific for the B component, antibodies 1A12 and 8B12 were specific for the L2 component, and antibody 1C2 was specific for the L1 protein of the HBL enterotoxin complex. No cross-reactivity with other proteins produced by different strains ofB. cereus was observed for monoclonal antibodies 2A3, 1A12, and 8B12, whereas antibody 1C2 cross-reacted with an uncharacterized protein of approximately 93 kDa and with a 39-kDa protein, which possibly represents one component of the nonhemolytic enterotoxin complex. Antibody 2A12 finally showed a distinct reactivity withB. cereus sphingomyelinase. The monoclonal antibodies developed in this study were also successfully applied in indirect enzyme immunoassays for the characterization of the enterotoxic activity of B. cereus strains. About 50% of the strains tested were capable of producing the HBL enterotoxin complex, and it could be demonstrated that all strains producing HBL were also highly cytotoxic.
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Sulakvelidze, Alexander, Arnold Kreger, Aaron Joseph, Roy M. Robins-Browne, Alessio Fasano, Georges Wauters, Norma Harnett, Louis DeTolla, and J. Glenn Morris. "Production of Enterotoxin by Yersinia bercovieri, a Recently Identified Yersinia enterocolitica-Like Species." Infection and Immunity 67, no. 2 (February 1, 1999): 968–71. http://dx.doi.org/10.1128/iai.67.2.968-971.1999.
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ABSTRACT Yersinia bercovieri, a recently identified Y. enterocolitica-like species, produces a heat-stable enterotoxin (designated YbST) which has biologic activity in infant mice and increases short circuit current in Ussing chambers. Although YbST has some properties in common with the heat-stable enterotoxins of Y. enterocolitica (YST I and YST II), it appears to be a novel toxin because (i) it was not neutralized by anti-YST I antiserum, (ii) YbST-neutralizing antiserum did not neutralize YST I, and (iii)Y. bercovieri strains did not hybridize with genetic probes for yst I, yst II, and other known enterotoxins.
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Grispoldi, Luca, Paul Alexanderu Popescu, Musafiri Karama, Vito Gullo, Giusi Poerio, Elena Borgogni, Paolo Torlai, et al. "Study on the Growth and Enterotoxin Production by Staphylococcus aureus in Canned Meat before Retorting." Toxins 11, no. 5 (May 23, 2019): 291. http://dx.doi.org/10.3390/toxins11050291.
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Possible contamination by Staphylococcus aureus of the production environment and of the meat of a canned meat production factory was analysed. A total of 108 samples were taken from nine critical control points, 13 of them were positive for S. aureus. None of the isolates produced enterotoxins. To determine how much time can elapse between can seaming and sterilisation in the autoclave without any risk of enterotoxin production by S. aureus, the growth and enterotoxin production of three enterotoxin A producing strains of S. aureus (one ATCC strain and two field strains) in canned meat before sterilisation was investigated at three different temperatures (37, 20 and 10 °C). Two types of meat were used, one with and one without sodium nitrite. In the canned products, the spiked bacteria spread throughout the meat and reached high levels. Enterotoxin production was shown to start 10 hours after incubation at 37 °C and after 48 h after incubation at 20 °C; the production of enterotoxin was always detected in the transition between the exponential and the stationary growth phase. At 10 °C, the enterotoxin was never detected. The statistical analysis of the data showed that the difference between the two different types of meat was not statistically significant (p value > 0.05). Since it is well known that following heat treatment, staphylococcal enterotoxins, although still active (in in vivo assays), can be undetectable (loss of serological recognition) depending on the food matrix and pH, it is quite difficult to foresee the impact of heat treatment on enterotoxin activity. Therefore, although the bacteria are eliminated, the toxins may remain and cause food poisoning. The significance of the results of this study towards implementing good manufacturing practices and hazard analysis critical control points in a canned meat factory are discussed with reference to the management of pre-retorting steps after seaming.
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Munson, Sibyl H., Mary T. Tremaine, Marsha J. Betley, and Rodney A. Welch. "Identification and Characterization of Staphylococcal Enterotoxin Types G and I fromStaphylococcus aureus." Infection and Immunity 66, no. 7 (July 1, 1998): 3337–48. http://dx.doi.org/10.1128/iai.66.7.3337-3348.1998.
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ABSTRACT Staphylococcal enterotoxins are exotoxins produced byStaphylococcus aureus that possess emetic and superantigenic properties. Prior to this research there were six characterized enterotoxins, staphylococcal enterotoxin types A to E and H (referred to as SEA to SEE and SEH). Two new staphylococcal enterotoxin genes have been identified and designated segand sei (staphylococcal enterotoxin types G and I, respectively). seg and sei consist of 777 and 729 nucleotides, respectively, encoding precursor proteins of 258 (SEG) and 242 (SEI) deduced amino acids. SEG and SEI have typical bacterial signal sequences that are cleaved to form toxins with 233 (SEG) and 218 (SEI, predicted) amino acids, corresponding to mature proteins of 27,043 Da (SEG) and 24,928 Da (SEI). Biological activities for SEG and SEI were determined with recombinant S. aureus strains. SEG and SEI elicited emetic responses in rhesus monkeys upon nasogastric administration and stimulated murine T-cell proliferation with the concomitant production of interleukin 2 (IL-2) and gamma interferon (IFN-γ), as measured by cytokine enzyme-linked immunoassays. SEG and SEI are related to other enterotoxins of S. aureus and to streptococcal pyrogenic exotoxin A (SpeA) and streptococcal superantigen (SSA) of Streptococcus pyogenes. Phylogenetic analysis and comparisons of amino acid and nucleotide sequence identities were performed on related staphylococcal and streptococcal protein toxins to group SEG and SEI among the characterized toxins. SEG is most similar to SpeA, SEB, SEC, and SSA (38 to 42% amino acid identity), while SEI is most similar to SEA, SEE, and SED (26 to 28% amino acid identity). Polyclonal antiserum was generated against purified histidine-tagged SEG and SEI (HisSEG and HisSEI). Immunoblot analysis of the enterotoxins, toxic-shock syndrome toxin 1, and SpeA with antiserum prepared against HisSEG and HisSEI revealed that SEG shares some epitopes with SEC1 while SEI does not.
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LOPES, Ana Carolina Amaral, Luciano Moura MARTINS, Maria Silvia Viccari GATTI, Cristhiane Moura FALAVINA DOS REIS, Ernesto HOFER, and Tomomasa YANO. "DIARRHEA OUTBREAK IN PERNAMBUCO, BRAZIL, ASSOCIATED WITH A HEAT-STABLE CYTOTOXIC ENTEROTOXIN PRODUCED BY Aeromonas caviae." Revista do Instituto de Medicina Tropical de São Paulo 57, no. 4 (August 2015): 349–51. http://dx.doi.org/10.1590/s0036-46652015000400013.
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SUMMARY In the present study enterotoxic and cytotoxic activities of twenty Aeromonas caviaestrains were examined. They originated from fecal specimens of patients with acute diarrhea during an outbreak in Brazil in 2004. Culture supernatants of fourteen strains (70%) caused fluid accumulation in rabbit ileal intestinal loops and in suckling mice assays, and also showed a cytotoxic activity in Vero and Caco-2 cells. The enterotoxic and cytotoxic factors were heat-stable after culture supernatants treatment at 100 ºC. The results revealed that A. caviaestrains produce a putative diarrheagenic virulence factor, a heat-stable cytotoxic enterotoxin that could be linked to the diarrhea outbreak that took place in Brazil.
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BARON, FLORENCE, MARIE-FRANÇOISE COCHET, NOËL GROSSET, MARIE-NOËLLE MADEC, ROMAIN BRIANDET, SABINE DESSAIGNE, SÉVERINE CHEVALIER, MICHEL GAUTIER, and SOPHIE JAN. "Isolation and Characterization of a Psychrotolerant Toxin Producer, Bacillus weihenstephanensis, in Liquid Egg Products." Journal of Food Protection 70, no. 12 (December 1, 2007): 2782–91. http://dx.doi.org/10.4315/0362-028x-70.12.2782.
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A psychrotolerant bacteria of the Bacillus cereus group was found responsible for the spoilage of whole liquid egg products. By sequencing a 16S rRNA region and performing a PCR amplification of specific 16S rRNA and cspA signatures, a Bacillus weihenstephanensis was identified. Characterization of this strain shows its ability to grow in defined medium as well as in whole liquid egg at refrigerated temperatures. The strain isolated possesses genes encoding for hemolysin BL, nonhemolytic enterotoxin, and B. cereus enterotoxins and produces enterotoxins with cytotoxic activity in whole liquid egg, even at refrigerated temperatures. The isolate exhibits a clear ability to stick and form biofilms on stainless steel, the most common material used in egg breaking factories, as well as on model hydrophilic (glass) and hydrophobic (polytetrafluoroethylene) materials. These findings show the necessity to monitor for Bacillus contamination in egg products that are often used in the composition of particularly susceptible finished products such as cream, dessert, dairy, meat, and seafood.
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Moura, Emmanuella O., Adriano H. N. Rangel, Cláudia S. Macêdo, Stela A. Urbano, Luciano P. Novaes, and Dorgival M. Lima Júnior. "Enterotoxin-encoding genes in Staphylococcus aureus from buffalo milk." Pesquisa Veterinária Brasileira 39, no. 8 (August 2019): 587–91. http://dx.doi.org/10.1590/1678-5150-pvb-6011.
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ABSTRACT: This paper investigated the occurrence of Staphylococcus aureus and the detection of enterotoxin-encoding genes of these strains in milk collected from 30 Murrah buffaloes used to produce dairy products in Brazil. A total of 68 strains of Staphylococcus aureus were found as identified by conventional laboratory tests, and thus screened for sea, seb, sec, sed, see, seg, seh and sei enterotoxin-encoding genes by polymerase chain reaction (PCR). Twelve strains containing enterotoxin-amplified genes were found, with higher expression for the sei and seh genes. These results can be attributed to animal health and inadequate cleaning of the equipment, indicating the need for better quality control in animal production and health lines. The results of this study with the presence of pathogens and their enterotoxigenic potential indicate a source of food poisoning, as well as being a pioneering study in the detection of new enterotoxins for buffalo milk.
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DAMBROSIO, ANGELA, NICOLETTA CRISTIANA QUAGLIA, MARA SARACINO, MARIA MALCANGI, COSIMO MONTAGNA, MARCELLO QUINTO, VANESSA LORUSSO, and GIOVANNI NORMANNO. "Microbiological Quality of Burrata Cheese Produced in Puglia Region: Southern Italy." Journal of Food Protection 76, no. 11 (November 1, 2013): 1981–84. http://dx.doi.org/10.4315/0362-028x.jfp-13-067.
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Burrata cheese is a popular typical Italian food product, produced in Puglia (an administrative region of southern Italy), and this study investigated the microbiological quality of 404 samples of this cheese. The samples were analyzed in order to quantify Escherichia coli and to detect the presence of Staphylococcus aureus, Salmonella spp., and Listeria monocytogenes. No sample exceeded the values of E. coli set by EC Regulation 1441/07 for some dairy products, while 15 (3.7%) samples tested coagulase-positive staphylococci positive, with values greater than 103 CFU/g. One strain of S. aureus was identified and characterized from each of these positive samples, and of these strains, 7 (46.6%) produced staphylococcal enterotoxin A, 5 (33.3%) produced staphylococcal enterotoxin C, 2 (13.3%) produced staphylococcal enterotoxin D, and 1 (6.6%) produced both staphylococcal enterotoxins A and D. All strains were mecA negative. The 15 S. aureus isolates were tested for their antimicrobial resistance patterns, and all analyzed strains showed antimicrobial resistance properties for at least one of the tested antibiotics. Testing for the other pathogens mentioned above gave negative results. The results of our study mean that the microbiological quality of Burrata cheese can be assumed to be good, although care must be taken with raw materials and good hygiene during processing in order to guarantee greater food safety.
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GOMEZ-LUCIA, ESPERANZA, JOAQUIN GOYACHE, JOSE L. BLANCO, JOSE F. F. GARAYZABAL, JOSE A. ORDEN, and GUILLERMO SUAREZ. "Growth of Staphylococcus aureus and Enterotoxin Production in Homemade Mayonnaise Prepared with Different pH Values." Journal of Food Protection 50, no. 10 (October 1, 1987): 872–75. http://dx.doi.org/10.4315/0362-028x-50.10.872.
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The ability of Staphylococcus aureus to grow and produce enterotoxins in homemade mayonnaise prepared at different pH values was studied. Ten enterotoxigenic strains, producing one or two enterotoxin types (A, B, C, or D) were inoculated into mayonnaise samples with pH adjusted to values ranging between 4.0 and 5.8, and incubated at 37°C for 7 d. Counts were made on days 1, 3, 5, and 7 and extracts were prepared on day 7 to detect enterotoxin by ELISA. An important difference was seen between those samples prepared with pH below or equal to 4.9 and those over or equal to 5.0; in the range of pH between 4.0 and 4.9 the average of staphylococcal population was 100 CFU/g; at pH 5.0 it was 1.6 × 105, and at pH 5.15 and above it was at least 8 × 106 CFU/g. Enterotoxin was detected only at initial pH over 5.15 and when final pH was not less than 4.7. The highest amount of enterotoxin corresponded to 157.8 ng of SEB/100 g of mayonnaise.
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Minh, Nghiêm Ngọc, Nguyễn Thị Hoài Thu, Phạm Thùy Linh, Thân Đức Dương, Vũ Thị Thu Hằng, and Lê Văn Phan. "Screening of hybridoma cell lines secreting monoclonal antibodies specific for staphylococcal enterotoxin B (SEB) derived from Staphylococcus aureus." Vietnam Journal of Biotechnology 14, no. 1 (March 30, 2016): 23–28. http://dx.doi.org/10.15625/1811-4989/14/1/9288.
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Staphylococcus aureus (S. aureus) produces 11 types of toxins and more than 20 different Staphylococcal enterotoxins (SEs), including SEA to SEE, SEG to SER and SEU. Among them, enterotoxin type B (Staphylococcal enterotoxin B - SEB) is quite heat stable and causes gastrointestinal diseases in food poisoning. The symptoms of SEB intoxication begin with the onset of sudden fever, about 40oC to 41oC, chills, headache, muscle aches and dry cough. Some patients feel shortness of breath and chest pain. Although SEB is not considered lethal, high level of exposure can lead to shock and death. Therefore, a nontoxic SEB recombinant antigen was produced to immunize mice to create B lymphocytes. Myeloma cells were fused with the B lymphocytes to generate hybridoma lines. The screening of monoclonal antibodies for the SEB antigen was determined by ELISA and Western blot tests. This study demonstrates that an SEB recombinant antigen can immunize a response against SEB in BALB/c mice. The production of monoclonal antibodies will be used to make a rapid detection strip for SEB based on immunochromatography.
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Singh, Itender, and Jugsharan S. Virdi. "Production of Yersinia stable toxin (YST) and distribution of yst genes in biotype 1A strains of Yersinia enterocolitica." Journal of Medical Microbiology 53, no. 11 (November 1, 2004): 1065–68. http://dx.doi.org/10.1099/jmm.0.45527-0.
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Two hundred and fifty nine isolates of Yersinia enterocolitica and related species were examined for the production of heat-stable enterotoxin (Yersinia stable toxin; YST) as well as for the prevalence of enterotoxin genes, viz. ystA, ystB and ystC. Under the conventional conditions used for the production of Y. enterocolitica enterotoxin, i.e. in tryptic soy broth (TSB) supplemented with yeast extract at 28 °C for 48 h, 77.7 % of clinical isolates and 62.3 % of swine isolates showed enterotoxigenicity in infant mice. All isolates that produced enterotoxin at 28 °C also showed enterotoxic activity at 37 °C after 48 h incubation under an alkaline pH of 7.5, the pH present in the ileum. All Yersinia intermedia and Yersinia frederiksenii isolates were negative for enterotoxin production. All clinical isolates and 96.3 % of Y. enterocolitica isolates from swine hybridized with a probe for ystB, which indicated that the ystB gene was most prevalent in Y. enterocolitica biotype 1A strains. None of the Y. enterocolitica isolates showed hybridization with oligonucleotide probes for ystA or ystC. The study indicated that YST-b was the major contributor to diarrhoea produced by biotype 1A strains of Y. enterocolitica.
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Necidová, Lenka, Bohdana Janštová, and Renata Karpíšková. "Dynamics of staphylococcal enterotoxin production in model experiments simulating the fresh cheese environment." Acta Veterinaria Brno 81, no. 4 (2012): 391–96. http://dx.doi.org/10.2754/avb201281040391.
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The aim of this study was to evaluate the impact of internal factors (pH, NaCl) and external factors (temperature, incubation time) on the ability of Staphylococcus aureus to grow and to produce staphylococcal enterotoxins SEA, SEB, and SEC. The fresh cheese environment was modelled in Brain Heart Infusion Broth media and food matrices (pasteurized milk from retail outlets) by internal and external factors (pH = 4.5 and 5.5, 2% NaCl, and t = 8 °C and 15 °C). The counts of enterotoxigenic strains of S. aureus at baseline, i.e. at the time of inoculation of model samples, corresponded to those encountered in the production of fresh cheeses as a result of post-pasteurization contamination. Enumeration of S. aureus was performed in accordance with EN ISO 6888-1, using agar medium. Staphylococcal enterotoxins were detected by the enzyme-linked fluorescence assay. The pH (4.5) and refrigeration temperature (8 °C) used prevented S. aureus from achieving the critical count of 105 cfu·ml-1 specified in Commission Regulation (EC) No. 2073/2005. The highest rates of enterotoxin production were recorded for enterotoxin A. The growth curves of S. aureus derived from model experiments were compared with the growth curve generated by a predictive microbiology program - Pathogen Modelling Program. The results of this study proved the Pathogen Modelling Program to be suitable for use in the Hazard Analysis Critical Control Points system in the process of the fresh cheese production to help manufacturers prevent the growth of S. aureus and enterotoxin production.
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HARIRAM, UPASANA, and RONALD LABBÉ. "Spore Prevalence and Toxigenicity of Bacillus cereus and Bacillus thuringiensis Isolates from U.S. Retail Spices." Journal of Food Protection 78, no. 3 (March 1, 2015): 590–96. http://dx.doi.org/10.4315/0362-028x.jfp-14-380.
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Recent incidents of foodborne illness associated with spices as the vehicle of transmission prompted this examination of U.S. retail spices with regard to Bacillus cereus. This study focused on the levels of aerobic-mesophilic spore-forming bacteria and B cereus spores associated with 247 retail spices purchased from five states in the United States. Samples contained a wide range of aerobic-mesophilic bacterial spore counts (< 200 to 8.3 × 107 CFU/g), with 19.1% of samples at levels above 105 CFU/g. For examples, paprika, allspice, peppercorns, and mixed spices had high levels of aerobic spores (>107 CFU/g). Using a novel chromogenic agar, B. cereus and B. thuringiensis spores were isolated from 77 (31%) and 11 (4%) samples, respectively. Levels of B. cereus were <3 to 1,600 MPN/g. Eighty-eight percent of B. cereus isolates and 91%of B. thuringiensis isolates possessed at least one type of enterotoxin gene: HBL (hemolysin BL) or nonhemolytic enterotoxin (NHE). None of the 88 isolates obtained in this study possessed the emetic toxin gene (ces). Using commercially available immunological toxin detection kits, the toxigenicity of the isolates was confirmed. The NHE enterotoxin was expressed in 98% of B. cereus and 91% of B. thuringiensis isolates that possessed the responsible gene. HBL enterotoxin was detected in 87% of B. cereus and 100% of B. thuringiensis PCR-positive isolates. Fifty-two percent of B. cereus and 54% of B. thuringiensis isolates produced both enterotoxins. Ninety-seven percent of B. cereus isolates grew at 12°C, although only two isolates grew well at 9°C. The ability of these spice isolates to form spores, produce diarrheal toxins, and grow at moderately abusive temperatures makes retail spices an important potential vehicle for foodborne illness caused by B. cereus strains, in particular those that produce diarrheal toxins.
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Albert, M. John, M. Ansaruzzaman, Kaisar A. Talukder, Ashok K. Chopra, Inger Kuhn, Motiur Rahman, A. S. G. Faruque, M. Sirajul Islam, R. Bradley Sack, and Roland Mollby. "Prevalence of Enterotoxin Genes in Aeromonas spp. Isolated From Children with Diarrhea, Healthy Controls, and the Environment." Journal of Clinical Microbiology 38, no. 10 (2000): 3785–90. http://dx.doi.org/10.1128/jcm.38.10.3785-3790.2000.
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Aeromonads are causative agents of a number of human infections. Even though aeromonads have been isolated from patients suffering from diarrhea, their etiological role in gastroenteritis is unclear. In spite of a number of virulence factors produced byAeromonas species, their association with diarrhea has not been clearly linked. Recently, we have characterized a heat-labile cytotonic enterotoxin (Alt), a heat-stable cytotonic enterotoxin (Ast), and a cytotoxic enterotoxin (Act) from a diarrheal isolate ofAeromonas hydrophila. Alt and Ast are novel enterotoxins which are not related to cholera toxin; Act is aerolysin related and has hemolytic, cytotoxic, and enterotoxic activities. We studied the distribution of the alt, ast, andact enterotoxin genes in 115 of 125 aeromonads isolated from 1,735 children with diarrhea, in all 27 aeromonads isolated from 830 control children (P = 7 × 10−4for comparison of rates of isolation of aeromonads from cases versus those from controls), and in 120 randomly selected aeromonads from different components of surface water in Bangladesh.Aeromonas isolates which were positive only for the presence of the alt gene had similar distributions in the three sources; the number of isolates positive only for the presence of the ast gene was significantly higher for the environmental samples than for samples from diarrheal children; and isolates positive only for the presence of the act gene were not found in any of the three sources. Importantly, the number of isolates positive for both the alt and ast genes was significantly higher for diarrheal children than for control children and the environment. Thus, this is the first study to indicate that the products of both the alt and ast genes may synergistically act to induce severe diarrhea. In 26 patients,Aeromonas spp. were isolated as the sole enteropathogen. Analysis of clinical data from 11 of these patients suggested that isolates positive for both the alt and astgenes were associated with watery diarrhea but that isolates positive only for the alt gene were associated with loose stools. Most of the isolates from the three sources could be classified into seven phenospecies and eight hybridization groups. For the first time,Aeromonas eucrenophila was isolated from two children, one with diarrhea and another without diarrhea.
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Asadpoor, Mostafa, Georgia-Nefeli Ithakisiou, Paul A. J. Henricks, Roland Pieters, Gert Folkerts, and Saskia Braber. "Non-Digestible Oligosaccharides and Short Chain Fatty Acids as Therapeutic Targets against Enterotoxin-Producing Bacteria and Their Toxins." Toxins 13, no. 3 (February 25, 2021): 175. http://dx.doi.org/10.3390/toxins13030175.
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Enterotoxin-producing bacteria (EPB) have developed multiple mechanisms to disrupt gut homeostasis, and provoke various pathologies. A major part of bacterial cytotoxicity is attributed to the secretion of virulence factors, including enterotoxins. Depending on their structure and mode of action, enterotoxins intrude the intestinal epithelium causing long-term consequences such as hemorrhagic colitis. Multiple non-digestible oligosaccharides (NDOs), and short chain fatty acids (SCFA), as their metabolites produced by the gut microbiota, interact with enteropathogens and their toxins, which may result in the inhibition of the bacterial pathogenicity. NDOs characterized by diverse structural characteristics, block the pathogenicity of EPB either directly, by inhibiting bacterial adherence and growth, or biofilm formation or indirectly, by promoting gut microbiota. Apart from these abilities, NDOs and SCFA can interact with enterotoxins and reduce their cytotoxicity. These anti-virulent effects mostly rely on their ability to mimic the structure of toxin receptors and thus inhibiting toxin adherence to host cells. This review focuses on the strategies of EPB and related enterotoxins to impair host cell immunity, discusses the anti-pathogenic properties of NDOs and SCFA on EPB functions and provides insight into the potential use of NDOs and SCFA as effective agents to fight against enterotoxins.
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Hennekinne, Jacques-Antoine, Martine Gohier, Tiphaine Maire, Christiane Lapeyre, Bertrand Lombard, and Sylviane Dragacci. "First Proficiency Testing To Evaluate the Ability of European Union National Reference Laboratories To Detect Staphylococcal Enterotoxins in Milk Products." Journal of AOAC INTERNATIONAL 86, no. 2 (March 1, 2003): 332–39. http://dx.doi.org/10.1093/jaoac/86.2.332.
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Abstract The European Commission has designed a network of European Union-National Reference Laboratories (EU-NRLs), coordinated by a Community Reference Laboratory (CRL), for control of hygiene of milk and milk products (Council Directive 92/46/ECC). As a common contaminant of milk and milk products such as cheese, staphylococcal enterotoxins are often involved in human outbreaks and should be monitored regularly. The main tasks of the EU-CRLs were to select and transfer to the EU-NRLs a reference method for detection of enterotoxins, and to set up proficiency testing to evaluate the competency of the European laboratory network. The first interlaboratory exercise was performed on samples of freeze-dried cheese inoculated with 2 levels of staphylococcal enterotoxins (0.1 and 0.25 ng/g) and on an uninoculated control. These levels were chosen considering the EU regulation for staphylococcal enterotoxins in milk and milk products and the limit of detection of the enzyme-linked immunosorbent assay test recommended in the reference method. The trial was conducted according to the recommendations of ISO Guide 43. Results produced by laboratories were compiled and compared through statistical analysis. Except for data from 2 laboratories for the uninoculated control and cheese inoculated at 0.1 ng/g, all laboratories produced satisfactory results, showing the ability of the EU-NRL network to monitor the enterotoxin contaminant.
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Godjevargova, Tzonka, Zlatina Becheva, Yavor Ivanov, and Andrey Tchorbanov. "Immunofluorescence Assay Using Monoclonal and Polyclonal Antibodies for Detection of Staphylococcal Enterotoxins A in Milk." Open Biotechnology Journal 13, no. 1 (November 15, 2019): 137–45. http://dx.doi.org/10.2174/187407070190130137.
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Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.
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Thu, Nguyễn Thị Hoài, and Nghiêm Ngọc Minh. "Staphylococcal enterotoxin B (SEB) toxin of Staphylococcus aureus and the detection methods." Vietnam Journal of Biotechnology 15, no. 2 (April 20, 2018): 211–21. http://dx.doi.org/10.15625/1811-4989/15/2/12336.
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Staphylococcal enterotoxins (SEs) secreted by Staphylococcus aureus is one of the principal causes of food poisoning. The SEs are superantigens; they are highly stable, resisting most proteolytic enzymes and thus keeping activity in the gastrointestinal tract after being ingestion. In particular, heat-stable enterotoxin is one of the most important property related to food safety. They are not degraded at 100°C for 30 minutes, even at 121oC for 28 minutes, the SEs retain biological activity. Heat resistance of SEs in foods is higher than in the culture medium. Staphylococcus aureus (S. aureus) produces more than 20 different types of enterotoxins, including SEA to SEE, SEG to SER and SEU. Among these, Staphylococcal enterotoxin B (SEB) is a powerful toxin, heat-stable, water-soluble and is a common cause of food poisoning. Moreover, SEB is one of the harmful or hazardous agents used as biological weapons in bioterrorism or biological warfare. Therefore, determining presence of SEB toxin in food is extremely important. In this review, we introduce the most basic features about S. aureus; about SEB toxin and conventional methods for SEB diagnosis, detection. Especially, we focus on rapid detection strip based on an immunochromatography; this technique is an highly sensitive, rapid, easy for use and storage.