Academic literature on the topic 'Hafnia alvei'

SUMMARY The genus Hafnia, a member of the family Enterobacteriaceae, consists of gram-negative bacteria that are occasionally implicated in both intestinal and extraintestinal infections in humans. Despite the fact that the genus currently contains only a single species (H. alvei), more extensive phylogenetic depth (two or more species) is apparent based upon DNA relatedness and 16S rRNA gene sequencing studies. Hafnia causes a variety of systemic infections, including septicemia and pneumonia; however, its role as a gastrointestinal pathogen is controversial. Many of the data supporting a role for hafniae as enteric pathogens were incorrectly attributed to this genus rather than to the actual pathogen, Escherichia albertii. There are numerous gaps in our understanding of this genus, including ecologic habitats and population genetics, disease-producing role in animals, phenetic and genetic methods useful in distinguishing genomospecies within the H. alvei complex, and bona fide pathogenicity factors.

It has been shown previously, based largely on DNA–DNA hybridizations and partial 16S rRNA gene sequencing, that Hafnia alvei is genotypically heterogeneous and consists of at least two DNA hybridization groups (HGs). In the present study, the taxonomic status of H. alvei HGs 1 and 2 was reassessed. A panel of 24 reference strains and isolates previously assigned to one of the two HGs in H. alvei was subjected to (GTG)5-PCR fingerprinting; this resulted in the delineation of two (GTG)5-PCR clusters in perfect accordance with the respective HG designations. Based on full 16S rRNA gene sequencing of a selection of reference strains, H. alvei HGs 1 and 2 showed internal sequence similarities of 99.8 and 99.5 %, respectively. Between the two groups, sequence similarities ranged from 98.8 to 99.1 %. Mean DNA–DNA hybridization values of 74.7–99.9 % were obtained within each of the two HGs, whereas cross-hybridizations between members of H. alvei HG 1 (including ATCC 13337T) and HG 2 revealed only 32.7–48.7 % DNA–DNA hybridization. Previously published and new phenotypic data revealed that a combination of malonate assimilation and β-glucosidase activity enabled correct assignment of Hafnia isolates to one of the two HGs. Collectively, taxonomic data from this study confirm that H. alvei comprises at least two taxa at the species level, of which HG 1 corresponds to H. alvei sensu stricto because it includes the type strain ATCC 13337T. Strains formerly classified as members of H. alvei HG 2 represent a novel species, for which the name Hafnia paralvei sp. nov. is proposed; ATCC 29927T (=CDC 4510-73T =LMG 24706T), the former reference strain of H. alvei HG 2, is designated the type strain.

Hafnia alvei, a Gram negative motile bacillus that belongs to Enterobacteriaceae family is rarely associated with infection in pediatric patients and is exceptionally rare in the neonatal period. H. alvei is ubiquitous in the environment, causing infections in debilitated and immuno-compromised patients with few cases being reported in neonates. We report two cases of late onset sepsis in term neonates caused by H. alvei that were successfully treated in our unit. To the best of our knowledge, infection due to H. alvei has not been reported in neonates from India. Hafnia alvei causes infection rarely in neonates. Because it can cause nosocomial outbreaks, awareness regarding this uncommon pathogen and initiation of appropriate antibiotic therapy improves the outcome and prevents mortality.

Syftet med denna magisteruppsats är att gå vidare med resultat från en kandidatuppsats (Westling, 2013) gällande opastöriserade franska mögel- och kittostar genom att undersöka vilka Enterobacteriaceae-arter som ett urval av de analyserade ostarna innehöll. API 20E används som identifieringssystem. Tre Enterobacteriaceae-arter gav acceptabel till utmärkt identifiering av 40 analyserade isolat från de fyra ostarna, nämligen Hafnia alvei, Escherichia coli och Klebsiella pneumoniae. Inga skillnader mellan de identifierade arterna vad gäller inverkan på smak- och doftupplevelser hos opastöriserade franska mögel- och kittostar gick att urskilja med tillgänglig sensorisk data från kandidatuppsatsen (Westling, 2013). Utifrån denna magisteruppsats räcker det inte med att dofta på ostarna för att säkerställa hygienisk kvalitet, ytterligare undersökningar behövs för att kunna identifiera vilka Enterobacteriaceae-arter de innehåller. Däremot skulle en förstudie i form av en sensorisk bedömning av opastöriserade mögel- och kittostar kunna påvisa om ett högt antal Enterobacteriaceae föreligger, vilka vid konsumtion kan vara sjukdomsframkallande.

L’objectif de ce travail était de mieux comprendre les mécanismes moléculaires de l’adaptation microbienne à l’environnement fromager par des approches de génomique fonctionnelle via le modèle de Brevibacterium, un genre bactérien largement utilisé en technologie fromagère, mais dont l’implantation est parfois difficile à maîtriser.L’analyse génomique comparative de 23 souches de Brevibacterium, dont 12 issues de fromages, a révélé des différences en déterminants génétiques impliqués dans la capacité à croître à la surface du fromage. Parmi ces différences, plusieurs sont corrélées à la phylogénie des souches, et d’autres résultent de transferts horizontaux, notamment dans le cas des gènes liés à l’acquisition du fer et à la biosynthèse de bactériocines. Nous avons identifié des îlots génomiques correspondant à des transferts de gènes d’acquisition du fer entre des souches fromagères de Brevibacterium et des bactéries d’affinage appartenant à d’autres genres. Nous avons également mis en évidence un transposon conjugatif codant pour la synthèse de bactériocines présent chez des souches de Brevibacterium d'origine fromagère mais aussi chez une souche fromagère du genre Corynebacterium.L’étude fonctionnelle des interactions biotiques entre Brevibacterium et Hafnia alvei, une autre bactérie d’affinage du fromage, a été menée dans un modèle fromager développé au cours de ce travail. En couplant des analyses microbiologiques, biochimiques et transcriptomiques (RNA-seq), nous avons mis en évidence l’existence de différents mécanismes d’interaction entre ces bactéries. Ceux-ci concernent notamment l’acquisition du fer, la protéolyse, la lipolyse, le métabolisme soufré et le catabolisme du D-galactonate. Nos résultats suggèrent que dans la relation mutualiste observée entre certaines souches de Brevibacterium et H. alvei, cette dernière sécrète des sidérophores qui sont utilisés par Brevibacterium pour capter le fer plus efficacement, stimulant ainsi sa croissance. En contrepartie, Brevibacterium sécrète des lipases et des protéases qui dégradent les caséines et triglycérides du fromage en constituants énergétiques favorisant la croissance de H. alvei. Ce type d’interaction est intéressant à considérer pour la formulation des ferments d'affinage car il en résulte une meilleure capacité de tous les partenaires à coloniser le fromage, et ainsi à générer les propriétés technologiques recherchées<br>The objective of this study was to better understand the molecular mechanisms of microbial adaptation to the cheese habitat by functional genomic approaches using Brevibacterium as a model microorganism. This bacterium is widely used for the manufacturing of cheese but its growth on the cheese surface is sometimes difficult to control.Comparative genomic analysis of 23 Brevibacterium strains, including 12 strains isolated from cheeses, revealed differences in genetic determinants involved in the growth on the cheese surface. Some of them are correlated to strain phylogeny and others are the result of gene transfers, especially those involved in iron acquisition and bacteriocin biosynthesis. We identified genomic islands corresponding to transfers of genes involved in iron acquisition between cheese-associated Brevibacterium strains and cheese-associated strains belonging to other genera. We also detected a conjugative transposon encoding bacteriocin production, which is present in cheese-associated Brevibacterium strains as well as in a cheese-associated Corynebacterium strain.Functional study of biotic interactions between Brevibacterium and Hafnia alvei, another cheese-ripening bacterium, was performed in a model cheese developed in this study. By coupling microbial, biochemical and transcriptomic (RNA-seq) analyses, we revealed several interaction mechanisms between these bacteria. These concern, in particular, iron acquisition, proteolysis, lipolysis, sulfur metabolism and D-galactonate catabolism. Our findings suggest that in the mutualistic relationship between some Brevibacterium strains and H. alvei, the latter stimulates Brevibacterium growth by the secretion of siderophores, which can be used by Brevibacterium to capture iron more efficiently. In return, Brevibacterium secretes lipases and proteases, which degrade cheese caseins and triglycerides into energetic substrates that stimulate H. alvei growth. This type of interaction is interesting to consider in the formulation of ripening cultures because it results in a better ability of all partners to colonize the cheese, and thus to generate the desired technological properties

L’objectif de ce travail était de mieux comprendre les mécanismes moléculaires de l’adaptation microbienne à l’environnement fromager par des approches de génomique fonctionnelle via le modèle de Brevibacterium, un genre bactérien largement utilisé en technologie fromagère, mais dont l’implantation est parfois difficile à maîtriser.L’analyse génomique comparative de 23 souches de Brevibacterium, dont 12 issues de fromages, a révélé des différences en déterminants génétiques impliqués dans la capacité à croître à la surface du fromage. Parmi ces différences, plusieurs sont corrélées à la phylogénie des souches, et d’autres résultent de transferts horizontaux, notamment dans le cas des gènes liés à l’acquisition du fer et à la biosynthèse de bactériocines. Nous avons identifié des îlots génomiques correspondant à des transferts de gènes d’acquisition du fer entre des souches fromagères de Brevibacterium et des bactéries d’affinage appartenant à d’autres genres. Nous avons également mis en évidence un transposon conjugatif codant pour la synthèse de bactériocines présent chez des souches de Brevibacterium d'origine fromagère mais aussi chez une souche fromagère du genre Corynebacterium.L’étude fonctionnelle des interactions biotiques entre Brevibacterium et Hafnia alvei, une autre bactérie d’affinage du fromage, a été menée dans un modèle fromager développé au cours de ce travail. En couplant des analyses microbiologiques, biochimiques et transcriptomiques (RNA-seq), nous avons mis en évidence l’existence de différents mécanismes d’interaction entre ces bactéries. Ceux-ci concernent notamment l’acquisition du fer, la protéolyse, la lipolyse, le métabolisme soufré et le catabolisme du D-galactonate. Nos résultats suggèrent que dans la relation mutualiste observée entre certaines souches de Brevibacterium et H. alvei, cette dernière sécrète des sidérophores qui sont utilisés par Brevibacterium pour capter le fer plus efficacement, stimulant ainsi sa croissance. En contrepartie, Brevibacterium sécrète des lipases et des protéases qui dégradent les caséines et triglycérides du fromage en constituants énergétiques favorisant la croissance de H. alvei. Ce type d’interaction est intéressant à considérer pour la formulation des ferments d'affinage car il en résulte une meilleure capacité de tous les partenaires à coloniser le fromage, et ainsi à générer les propriétés technologiques recherchées<br>The objective of this study was to better understand the molecular mechanisms of microbial adaptation to the cheese habitat by functional genomic approaches using Brevibacterium as a model microorganism. This bacterium is widely used for the manufacturing of cheese but its growth on the cheese surface is sometimes difficult to control.Comparative genomic analysis of 23 Brevibacterium strains, including 12 strains isolated from cheeses, revealed differences in genetic determinants involved in the growth on the cheese surface. Some of them are correlated to strain phylogeny and others are the result of gene transfers, especially those involved in iron acquisition and bacteriocin biosynthesis. We identified genomic islands corresponding to transfers of genes involved in iron acquisition between cheese-associated Brevibacterium strains and cheese-associated strains belonging to other genera. We also detected a conjugative transposon encoding bacteriocin production, which is present in cheese-associated Brevibacterium strains as well as in a cheese-associated Corynebacterium strain.Functional study of biotic interactions between Brevibacterium and Hafnia alvei, another cheese-ripening bacterium, was performed in a model cheese developed in this study. By coupling microbial, biochemical and transcriptomic (RNA-seq) analyses, we revealed several interaction mechanisms between these bacteria. These concern, in particular, iron acquisition, proteolysis, lipolysis, sulfur metabolism and D-galactonate catabolism. Our findings suggest that in the mutualistic relationship between some Brevibacterium strains and H. alvei, the latter stimulates Brevibacterium growth by the secretion of siderophores, which can be used by Brevibacterium to capture iron more efficiently. In return, Brevibacterium secretes lipases and proteases, which degrade cheese caseins and triglycerides into energetic substrates that stimulate H. alvei growth. This type of interaction is interesting to consider in the formulation of ripening cultures because it results in a better ability of all partners to colonize the cheese, and thus to generate the desired technological properties

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-06-28T09:33:23Z No. of bitstreams: 1 texto completo.pdf: 1338198 bytes, checksum: 5403979ea8250d61a6a0c78ac9f2e904 (MD5)<br>Made available in DSpace on 2016-06-28T09:33:23Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1338198 bytes, checksum: 5403979ea8250d61a6a0c78ac9f2e904 (MD5) Previous issue date: 2008-07-30<br>Fundação de Amparo à Pesquisa do Estado de Minas Gerais<br>Quando em alta densidade populacional, muitas bactérias são capazes de coordenar a expressão de genes via produção e recepção de sinais químicos, por meio de mecanismo denominado quorum sensing. O objetivo deste trabalho foi obter mutantes HalI - das estirpes psicrotróficas isoladas do leite cru refrigerado, 068 e 071 de Hafnia alvei e 067 de Enterobacter cloacae. O gene halI codifica a sintase responsável pela produção de acil homoserina lactonas (AHLs) que são as moléculas sinalizadoras de quorum sensing em H. alvei e E. cloacae. Para obtenção dos mutantes, foi utilizado o vetor suicida pGP704, onde foi clonado o gene halI. Em seguida este gene foi interrompido com o gene que codifica a proteína gentamicina- 3-acetiltransferase, que confere resistência ao antibiótico gentamicina e o plasmídeo foi denominado pGP704halI068::Gm. A transformação das estirpes psicrotróficas com esse vetor resultou em transformantes resistentes a 25 μg mL -1 de gentamicina, mas que ainda produziam AHL, constatada por meio da indução da estirpe monitora de AHL, Chromobacterium violaceum CV 026. A inativação da expressão do gene halI no DNA cromossômico foi obtida após nova transformação desses transformantes com o vetor pUT::Tn5, pertencente ao mesmo grupo de compatibilidade de pGP704. O uso deste sistema de incompatibilidade propiciou a seleção de estirpes onde ocorreu a recombinação homóloga entre o gene halI interrompido pelo gene que confere resistência a gentamicina com o gene halI presente no DNA cromossômico. A confirmação da recombinação do gene halI inativado e clonado no plasmideo com o gene halI cromossômico, foi feita selecionando-se os transformantes em ágar Luria Bertani contendo 50 μg mL -1 de canamicina e gentamicina. Por ensaio de indução de C. violaceum CV026, foi confirmado que os transformantes resistentes a canamicina e gentamicina não induziram a produção do pigmento violaceína pela estirpe monitora. A inativação do gene halI no cromossoma torna essas estirpes ferramentas importantes para elucidação da regulação da expressão de genes pelo mecanismo de quorum sensing.<br>When population density is high, several bacteria are able to coordinate gene expression by production and reception of chemical signals by means of a mechanism called quorum sensing. The scope of this work was to produce HalI - mutants from psychotrophic bacterias found in fresh cooled milk, 068 and 071 of Hafnia alvei and 067 of Enterobacter cloacae. The halI gene encondes the synthase responsible for the production of acyl-homoserine lactones (AHLs) which are the signaling molecules of quorum sensing for H. alvei and E. cloacae. In order to produce the mutants, it was used the suicide vector pGP704, where the halI gene was cloned. After that, this gene was interrupted with a gene that encodes the protein gentamicin 3-acetyltransferase, responsible for giving resistance to the gentamicin antibiotic. This vector was called pGP704halI068::Gm. The transformation of psychotrophic strain with such vector resulted in transformants cells resistant to 25 μg mL -1 of gentamicin, but they would still produce AHL. AHL production was confirmed by the induction of the monitored strain of AHL, Chromobacterium violaceum CV 026. Expression inactivation of the hall gene in the chromosomic DNA was achieved after new transformation of former transformants with the pUT::Tn5 vector, which belong to the same compatible group of pGP704. The use of this system of incompatibility provided the selection of strain that showed homologous recombination between the hall gene interrupted by the gene that affords resistance to gentamicin and the hall gene of the present chromosomal DNA. Recombination assurance of the halI gene inactivated and cloned in the plasmidium with the halI chromosomic gene was done by selecting the transformants in Luria- Bertani agar containing 50 μg mL -1 of kanamicyn and gentamicin. By means of an induction trial of C. violaceum CV026, it was confirmed that the transformants resistant to kanamicyn and gentamicin did not induced the production of the violacein pigment by the strain being monitored. Inactivation of the halI gene in the chromosome makes these strains important tools for elucidating gene expression regulation by the quorum sensing mechanism.<br>Dissertação antiga

Cette thèse eu deux objectifs: A) Déterminer la présence de peptides bioactifs avec des activités antioxydantes ou inhibitrices d´enzyme de conversion de l'angiotensine (ECA) dans les fromages mexicains. B) Observer l'effet de la composition et de la structure de matrices laitières dans la survie des microorganismes laitières pendant la digestion. Les fromages ont été analysés séparément: fromage Cotija, affiné 6 mois et fromage de chèvre frais (non affiné) produit à partir de lait cru et pasteurisé. L´activité antioxydante a été plus élevé dans les fractions contenant des petits peptides. Le fromage Cotija jeune a donné des valeurs similaires au fromage de chèvre frais mais l'activité augmente pendant l´affinage (en raison de la production de peptides solubles). La pasteurisation n'a pas impacté l'activité antioxydante dans les fromages de chèvre frais. Cette activité a été corrélée avec les peptides hydrophiles. Les deux fromages ont une activité inhibitrice de l´ECA qui a été plus élevée dans le fromage de chèvre que dans le fromage Cotija jeune. Cette activité était corrélée avec les peptides hydrophobes. Les fromages de chèvre frais, fait avec du lait pasteurisés, ont une concentration en peptides hydrophobes plus élevé. La libération de peptides bioactifs dans le fromage a toujours été considérée comme dépendante de la protéolyse par action des microorganismes. Certains de ces microorganismes sont capables de survivre à la digestion et l'hypothèse que la présence d'une matrice alimentaire pourrait améliorer leur résistance pendant la digestion a été testée. Nous avons mesuré la viabilité des microorganismes; Streptococcus thermophilus, Brevibacterium aurantiacum et Hafnia alvei pendant la digestion (in vitro et in vivo). Les microorganismes ont été inclus dans des matrices laitières liquides et gélifiées avec et sans matière grasse: lait écrème (SM), lait entier (WM), gel présure de lait écrèmé (GSM) et gel présure de lait entier (GWM). La digestion in vitro a été réalisée sur un digesteur dynamique (DIDGI) qui simule l'estomac, le duodénum et l'intestin grêle. Les paramètres de la digestion ont été les mêmes pour toutes les matrices. La dégradation des matrices pendant digestion in vitro a été analysée par électrophorèse et GC-Mass. La microscopie confocale à balayage laser (CLSM) a été aussi réalisée pour observer la microstructure. Pendant la digestion in vitro, il a été montré que S. thermophilus était très sensible au stress gastrique, et n'a pas été trouvé dans le compartiment duodénale. B. auranticum était modérément sensible au stress gastrique, mais résistant au stress duodénale. H. alvei était très résistant aux deux stress, par contre aucun effet des matrices laitières n'a été observé. Les images de CLSM ont montré l'effet de l´acidité sur la survie des microorganismes. Mais les analyse in vivo n’ont pas réussi à confirmer les observations in vitro parce que les microorganismes testés ne sont pas détectés<br>This thesis was realized to respond to two particular objectives a) to determine the presence of bioactive peptides with activities as antioxidants and inhibitors of the angiotensin converting enzyme (ACE) in Mexican cheeses; and b), to observe the effect of composition and structure of dairy matrices in survival of dairy microorganism through digestion. Two Mexican cheeses were analyzed separately: Cotija cheeses ripened 6 months; and Fresh goat cheese (unripened) produced from raw and pasteurized milk. Studied cheeses had important antioxidant activity that was higher in fractions with smaller peptides. Young Cotija cheese had similar values than Fresh goat cheese. But activity increased throughout ripening (because of the production of soluble peptides). Milk pasteurization (Fresh goat cheeses) did not affect the antioxidant activity. This activity was correlated with the hydrophilic peptides. Also, both cheeses possess ACE inhibitor activity that was higher in Fresh goat cheese than in young Cotija cheese. This inhibitor activity was more correlated with the hydrophobic peptides. Pasteurization of Fresh goat cheeses increased the production of hydrophobic peptides. The release of bioactive peptides in cheeses has always been considered as dependent of the proteolysis caused by cheese microbiota. Some of these microorganisms are capable to survive digestion. It has been hypothesized that the presence of a food matrix could enhance their resistance through digestion.We measured the viability of three dairy microorganisms; Streptococcus thermophilus, Brevibacterium aurantiacum and Hafnia alvei during (in vitro and in vivo) digestion. Microorganisms were included in liquid and gel dairy matrices with and without fat: Skim milk (SM), whole milk (WM), rennet gel of skim milk (GSM) and rennet gel of whole milk (GWM). In vitro digestion was carried on with a dynamic digester (DIDGI) that simulated the stomach, duodenum and small intestine. Parameters of digestion were the same for all the matrices tested. The degradation of the dairy matrices through in vitro digestion was analyzed by electrophoreses and GC-Mass. Confocal laser scanning microscopy (CLSM) was performed to observe matrix microstructure.During in vitro digestion, the microorganisms had different survival rates; S. thermophilus was highly sensitive to gastric stress, and was not found in the duodenal compartment. B. auranticum was moderately sensitive to gastric stress but resistant to duodenal stress. H. alvei was highly resistant to both stresses. Despite its buffer capacity, we did not observe any effect of the dairy matrices on microorganisms survival. CLSM images, probed the effect of low pH on microorganisms survival. However our in vivo analyses failed to confirm in vitro observations and tested microorganisms were not detected

Fikolina H jest surowiczą cząsteczką rozpoznającą wzorce (PRR), posiadającą zdolność wiązania grup acetylowych i reszt cukrowych. Skompleksowana z proteazami serynowymi MASP fikolina wiąże ligandy na powierzchni drobnoustrojów, co prowadzi do aktywacji układu dopełniacza na drodze lektynowej. Pomimo, że fikolina H często w literaturze przedstawiana jest jako czynnik odporności wrodzonej, opisano jedynie kilka przykładów bakterii rozpoznawanych przez tę lektynę. Jedną z nich jest Hafnia alvei – oportunistyczny patogen, którego lipopolisacharyd (w przypadku niektórych szczepów) zawiera motywy cukrowe wiązane przez fikolinę H. Celem przedstawionej rozprawy doktorskiej było określenie roli fikoliny H w odporności wrodzonej. Badano zdolność tej cząsteczki do zabijania bakterii, modulacji odpowiedzi komórkowej na LPS i jej udział w aktywacji układu krzepnięcia. Ponadto, by ocenić kliniczne znaczenie przeciwzakaźne fikoliny H, mierzono stężenia tego białka (i cząsteczek występujących z nim w kompleksach) w próbach surowicy pacjentów poddawanych operacji korekcji wrodzonych wad serca. W niniejszej pracy dowiedziono, że fikolina H stanowi ważny czynnik odporności wrodzonej, który może działać na trzech różnych płaszczyznach. Po pierwsze, prowadzi do zabijania bakterii poprzez ich aglutynację, ułatwianie fagocytozy czy też w wyniku inicjacji kaskady dopełniacza, powodującej lizę komórki. Po drugie, fikolina H może przyczyniać do hamowania rozwoju infekcji poprzez unieruchomienie patogenu w miejscu zakażenia przez tworzący się skrzep. Wykazano bowiem, że badane białko bezpośrednio wiąże i aktywuje ludzki fibrynogen, przez co może uczestniczyć w aktywacji układu krzepnięcia. Po trzecie, udowodniono, że fikolina H jest zaangażowana w odpowiedź komórkową indukowaną endotoksyną. Preinkubacja fikoliny z LPS hamowała aktywację NF-κB w komórkach i wydzielanie chemokin prozapalnych. Jednak, mimo, że badania in vitro udowodniły anty-bakteryjny charakter fikoliny H, nie zaobserowano różnic w stężeniu tego białka między surowicami pacjentów bez powikłań a cierpiącymi na pooperacyjne zakażenia. Zaobserwowano natomiast niższe stężenia badanego białka i MAp44 (kontrolującego aktywację dopełniacza na drodze lektynowej) w próbach surowicy pacjentów z pooperacyjnym SIRS (z uszkodzeniami wielonarządowymi) w odniesieniu do grupy kontrolnej. Otrzymane wyniki wskazują na konieczność kontynuowania badań w celu wyjaśnienia klinicznego znaczenia fikoliny H wobec zakażeń.<br>Badania były finansowane: •ze środków Ministerstwa Nauki i Szkolnictwa Wyższego przyznanych na realizację projektu badawczego: „Badania molekularnych mechanizmów rozpoznawania bakteryjnych endotoksyn przez fikolinę H i analiza efektów biologicznych tego procesu (Grant N N401 267339, kierownik: Dr hab. Jolanta Łukasiewicz) •ze środków Narodowego Centrum Nauki przyznanych na realizację projektu badawczego: „Badanie znaczenia czynników aktywacji dopełniacza na drodze lektynowej dla rozwoju powikłań po operacji wad wrodzonych serca u dzieci z użyciem krążenia pozaustrojowego”(UMO- 2011/03/B/NZ6/00052, kierownik Dr hab. Izabela Pągowska–Klimek) •ze środków Narodowego Centrum Nauki przyznanych w ramach programu stypendialnego ETIUDA 3: „Badanie oddziaływania fikoliny H z endotoksynami bakteryjnymi i efekty biologiczne tych interakcji” (UMO-2015/16/T/NZ6/00412, beneficjent mgr Mateusz Michalski)

Thesis (M.S.)--University of Wisconsin--Madison, 1997.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 116-130).

Hafnia alvei HA4597® is a novel probiotic strain producing an anorexigenic mimetic protein. This report summarizes the innovative approach leading to the discovery of the precision probiotic H. alvei HA4597® and its benefits on body weight and metabolic parameters. H. alvei HA4597® has been identified after the striking findings on the effects of the bacterial metabolite ClpB (Caseinolytic peptidase B) on appetite regulation, through a screening of ClpB-producing strains. Its efficacy in humans has been validated by a multicentric, double-blind, randomized placebo-controlled trial including 236 overweight adults. The successful results on body weight loss of the clinical study support the use of H. alvei HA4597® in the global management of excess weight.