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1
Zhu, Yanbin, Shan Li, Dengxin Li, Chunyan Liu, and Fang Ma. "Bioflocculation behaviours of microbial communities in water treatment." Water Science and Technology 69, no. 4 (November 18, 2013): 694–702. http://dx.doi.org/10.2166/wst.2013.746.
Повний текст джерелаАнотація:
We studied the flocculation behaviours of microbial communities in 21 soil, wastewater and activated sludge samples to clarify the effects of culture medium types on flocculation ability and screening efficiency, and to analyze diverse functions and microbial compositions. The bioflocculants produced by 33% of the microbial communities had flocculating efficiencies higher than 90%. Six out of the eight microbial communities with efficiencies over 94% were screened from the culture medium using dibutyl phthalate (DBP) as the carbon source. BF-BCT, which was derived from the Chinese cabbage soil sample, had the highest flocculating efficiency (99.6%), species diversity and uniformity. Nine highly efficient strains were separated and purified from seven different microbial communities, indicating that flocculating microorganisms are widely distributed in ecosystems. The 16S rRNA gene testing shows that the eight bacterial and the one fungal strains are common soil microorganisms. The flocculating abilities of BB11 (Sphingobacterium multivorum) and SE3 (Galactomyces geotrichum) have never been reported hitherto. Six strains, including the most flocculating-active TB13 and JB17, were screened from the culture medium using DBP as the sole carbon source. In particular, we compared the performance of culture media and analyzed analogous microbial communities with a Biolog automatic micro-analysis system for the first time.
2
Jebun, Nessa, Md Zahangir Alam, Abdullah Al Mamun, and Raha Ahmad Raus. "Novel Myco-Coagulant Produced by Lentinus squarrosulus for Removal of Water Turbidity: Fungal Identification and Flocculant Characterization." Journal of Fungi 8, no. 2 (February 16, 2022): 192. http://dx.doi.org/10.3390/jof8020192.
Повний текст джерелаАнотація:
Several river water fungal strains (RWF-1 to RWF-6) were isolated to investigate the potential of having coagulant properties from the metabolites produced by the fungus. The myco-coagulant produced from the liquid-state process was characterized and tested for flocculation of kaolin water. Molecular identification of the fungal strain isolated from river water and characterization of the myco-coagulant produced by the strain are presented in this paper. The genomic DNA of the fungal 18S ribosomal ribonucleic-acid (rRNA) and 28S rRNA genes were used and the species was identified as Lentinus squarrosulus strain 7-4-2 RWF-5. The characterization of myco-coagulant by Fourier-transform infrared spectroscopy (FTIR) showed that hydroxyl, carbonyl, amide and amine groups as principal functional groups were present in the new myco-coagulant. The mean zeta potential value of the myco-coagulant was −7.0 mV while the kaolin solution was −25.2 mV. Chemical analyses of the extracellular myco-coagulant revealed that it contained total sugar (5.17 g/L), total carbohydrate (237 mg/L), protein (295.4 mg/L), glucosamine (1.152 mg/L); and exhibited cellulase activity (20 units/L) and laccase activity (6.22 units/L). Elemental analyses of C, H, O, N and S showed that the weight fractions of each element in the myco-coagulant was 40.9, 6.0, 49.8, 1.7 and 1.4%, respectively. The myco-coagulant showed 97% flocculation activity at a dose of 1.8 mg/L, indicating good flocculation performance compared to that of polyaluminum chloride (PAC). The present work revealed that the fungal strain, L. squarrosulus 7-4-2 RWF-5 is able to produce cationic bio-coagulant. The flocculation mechanism of the novel myco-coagulant was a combination of polymer bridging and charge neutralization.
3
Gregori, Christa, Walter Glaser, Ingrid E. Frohner, Cristina Reinoso-Martín, Steffen Rupp, Christoph Schüller, and Karl Kuchler. "Efg1 Controls Caspofungin-Induced Cell Aggregation of Candida albicans through the Adhesin Als1." Eukaryotic Cell 10, no. 12 (October 28, 2011): 1694–704. http://dx.doi.org/10.1128/ec.05187-11.
Повний текст джерелаАнотація:
ABSTRACTEchinocandin drugs such as caspofungin (CASP), micafungin, and anidulafungin inhibit fungal cell wall biogenesis by blocking Fks1-mediated β-glucan deposition into the cell surface. Candins have become suitable drugs to treat life-threatening diseases caused by several fungal species, includingCandida albicans, that are pathogenic for humans.Here, we present the discovery of a novel CASP-induced flocculation phenotype ofC. albicans, which formed large cell aggregates in the presence of CASP. High concentrations of sugars such as mannose or glucose inhibit CASP-induced flocculation and improve survival ofC. albicanscells exposed to CASP. Notably, exposure ofC. albicanscells to CASP triggers Efg1-dependent expression of the adhesinALS1and induces invasive growth on agar plates. Indeed, cells lacking either Efg1 or Als1 show strongly diminished CASP-induced flocculation, and the absence of Efg1 leads to marked CASP hypersensitivity. On the other hand, CASP-induced invasive growth is enhanced in cells lacking Efg1. Hence, CASP stress drives an Efg1-dependent response, indicating that this multifunctional transcriptional regulator, which is otherwise involved in filamentation, white-to-opaque switching, and virulence, also modulates cell wall remodeling upon CASP challenge. Taken together, our data suggest that CASP-induced cell wall damage activates Efg1 in parallel with the known cell integrity stress signaling pathway to coordinate cell wall remodeling.
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Muradov, Nazim, Mohamed Taha, Ana F. Miranda, Digby Wrede, Krishna Kadali, Amit Gujar, Trevor Stevenson, Andrew S. Ball, and Aidyn Mouradov. "Fungal-assisted algal flocculation: application in wastewater treatment and biofuel production." Biotechnology for Biofuels 8, no. 1 (2015): 24. http://dx.doi.org/10.1186/s13068-015-0210-6.
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Bhattacharya, Arghya, Anushree Malik, and Hitendra K. Malik. "A mathematical model to describe the fungal assisted algal flocculation process." Bioresource Technology 244 (November 2017): 975–81. http://dx.doi.org/10.1016/j.biortech.2017.08.062.
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Pei, Xuan-Yuan, Hong-Yu Ren, and Bing-Feng Liu. "Flocculation performance and mechanism of fungal pellets on harvesting of microalgal biomass." Bioresource Technology 321 (February 2021): 124463. http://dx.doi.org/10.1016/j.biortech.2020.124463.
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Bhattacharya, Arghya, Megha Mathur, Pushpendar Kumar, Sanjeev Kumar Prajapati, and Anushree Malik. "A rapid method for fungal assisted algal flocculation: Critical parameters & mechanism insights." Algal Research 21 (January 2017): 42–51. http://dx.doi.org/10.1016/j.algal.2016.10.022.
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Faustina Patricia, Maria, Purwono, and Mochamad Arief Budihardjo. "Dose of Biocoagulant-Mixing Rate Combinations for Optimum Reduction of COD in Wastewater." E3S Web of Conferences 31 (2018): 03018. http://dx.doi.org/10.1051/e3sconf/20183103018.
Повний текст джерелаАнотація:
Chemical oxygen demand (COD) in domestic wastewater can be treated using flocculation-coagulation process with addition of Oyster mushroom (Pleurotus ostreatus) in powder form as biocoagulant. The fungal cell wall of Oyster mushroom comprises of chitin that is high polyelectrolyte and can be function as an absorbent of heavy metals in wastewater. The effectiveness of flocculation-coagulation process in treating wastewater depends on dose of coagulant and mixing rate. Therefore, this study aims to determine the best combination of three variation of dose of biocoagulant which are 600 mg/l, 1000 mg/l, and 2000 mg/l and mixing rate which are 100 rpm, 125 rpm, and 150 rpm that give the most reduction of COD in the wastewater. The result indicates that the combination of 1000 mg/l of biocoagulant and 100 rpm of mixing rate were found to be the most optimum combination to treat COD in the wastewater with COD reduction of 47.7%.
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Douglas, Lois M., Li Li, Yang Yang, and A. M. Dranginis. "Expression and Characterization of the Flocculin Flo11/Muc1, a Saccharomyces cerevisiae Mannoprotein with Homotypic Properties of Adhesion." Eukaryotic Cell 6, no. 12 (December 2007): 2214–21. http://dx.doi.org/10.1128/ec.00284-06.
Повний текст джерелаАнотація:
ABSTRACT The Flo11/Muc1 flocculin has diverse phenotypic effects. Saccharomyces cerevisiae cells of strain background Σ1278b require Flo11p to form pseudohyphae, invade agar, adhere to plastic, and develop biofilms, but they do not flocculate. We show that S. cerevisiae var. diastaticus strains, on the other hand, exhibit Flo11-dependent flocculation and biofilm formation but do not invade agar or form pseudohyphae. In order to study the nature of the Flo11p proteins produced by these two types of strains, we examined secreted Flo11p, encoded by a plasmid-borne gene, in which the glycosylphosphatidylinositol anchor sequences had been replaced by a histidine tag. A protein of approximately 196 kDa was secreted from both strains, which upon purification and concentration, aggregated into a form with a very high molecular mass. When secreted Flo11p was covalently attached to microscopic beads, it conferred the ability to specifically bind to S. cerevisiae var. diastaticus cells, which flocculate, but not to Σ1278b cells, which do not flocculate. This was true for the 196-kDa form as well as the high-molecular-weight form of Flo11p, regardless of the strain source. The coated beads bound to S. cerevisiae var. diastaticus cells expressing FLO11 and failed to bind to cells with a deletion of FLO11, demonstrating a homotypic adhesive mechanism. Flo11p was shown to be a mannoprotein. Bead-to-cell adhesion was inhibited by mannose, which also inhibits Flo11-dependent flocculation in vivo, further suggesting that this in vitro system is a useful model for the study of fungal adhesion.
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Subramanian, S. Bala, Song Yan, R. D. Tyagi, and R. Y. Surampalli. "A New, Pellet-Forming Fungal Strain: Its Isolation, Molecular Identification, and Performance for Simultaneous Sludge-Solids Reduction, Flocculation, and Dewatering." Water Environment Research 80, no. 9 (September 2008): 840–52. http://dx.doi.org/10.2175/106143008x304703.
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Wormley, F. L., G. Heinrich, J. L. Miller, J. R. Perfect, and G. M. Cox. "Identification and Characterization of an SKN7 Homologue in Cryptococcus neoformans." Infection and Immunity 73, no. 8 (August 2005): 5022–30. http://dx.doi.org/10.1128/iai.73.8.5022-5030.2005.
Повний текст джерелаАнотація:
ABSTRACT Cryptococcus neoformans is an encapsulated fungal pathogen that primarily infects the central nervous system of immunocompromised individuals, causing life-threatening meningoencephalitis. The capacity of C. neoformans to subvert host defenses and disseminate by intracellular parasitism of alveolar macrophages in the immune-compromised host has led to studies to evaluate genes associated with C. neoformans resistance to oxidative stress. In the present study, we identify and characterize a C. neoformans homologue to SKN7, a transcription factor in Saccharomyces cerevisiae that regulates the oxidative stress response, cell cycle, and cell wall biosynthesis. To examine the contribution of SKN7 in the pathogenesis of fungal infections, we created skn7 mutants via targeted disruption. The skn7 mutants were observed to be more susceptible to reactive oxygen species in vitro and were significantly less virulent than the wild-type strain and a reconstituted strain as measured by cumulative survival in the mouse inhalational model. The Skn7 protein was observed to be important for expression of thioredoxin reductase in response to oxidative challenge. Interestingly, skn7 mutants were also observed to flocculate following in vitro culture, a novel phenotype not observed in skn7 mutants derived from other fungi. These findings demonstrate that SKN7 contributes to the virulence composite but is not required for pathogenicity in C. neoformans. In addition, flocculation of C. neoformans skn7 mutants suggests a potentially unique function of SKN7 not previously observed in other cryptococcal strains or skn7 mutants.
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Gao, Mei, Hui Wang, and LiJuan Zhu. "Quercetin Assists Fluconazole to Inhibit Biofilm Formations of Fluconazole-Resistant Candida Albicans in In Vitro and In Vivo Antifungal Managements of Vulvovaginal Candidiasis." Cellular Physiology and Biochemistry 40, no. 3-4 (2016): 727–42. http://dx.doi.org/10.1159/000453134.
Повний текст джерелаАнотація:
Background: Vulvovaginal candidiasis (VVC) is a common gynecological disease. Candida albicans is believed to be mainly implicated in VVC occurrence, the biofilm of which is one of the virulence factors responsible for resistance to traditional antifungal agents especially to fluconazole (FCZ). Quercetin (QCT) is a dietary flavonoid and has been demonstrated to be antifungal against C. albicans biofilm. Methods: 17 C. albicans isolates including 15 clinical ones isolated from VVC patients were employed to investigate the effects of QCT and/or FCZ on the inhibition of C. albicans biofilm. Results: We observed that 64 µg/mL QCT and/or 128 µg/mL FCZ could (i) be synergistic against 10 FCZ-resistant planktonic and 17 biofilm cells of C. albicans, (ii) inhibit fungal adherence, cell surface hydrophobicity (CSH), flocculation, yeast-to-hypha transition, metabolism, thickness and dispersion of biofilms; (iii) down-regulate the expressions of ALS1, ALS3, HWP1, SUN41, UME6 and ECE1 and up-regulate the expressions of PDE2, NRG1 and HSP90, and we also found that (iv) the fungal burden was reduced in vaginal mucosa and the symptoms were alleviated in a murine VVC model after the treatments of 5 mg/kg QCT and/or 20 mg/kg FCZ. Conclusion: Together with these results, it could be demonstrated that QCT could be a favorable antifungal agent and a promising synergist with FCZ in the clinical management of VVC caused by C. albicans biofilm.
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Milstein, O., A. Haars, F. Krause, and A. Hüttermann. "Decrease of Pollutant Level of Bleaching Effluents and Winning Valuable Products by Successive Flocculation and Microbial Growth." Water Science and Technology 24, no. 3-4 (August 1, 1991): 199–206. http://dx.doi.org/10.2166/wst.1991.0476.
Повний текст джерелаАнотація:
The bulk of organic matter from spent bleaching effluent (SBE), either from chlorination and extraction stages or a mixture of both, can be precipitated with polycationic polymers. The mixtures of polyethy-lenimine and modified (containing cationic side groups) starches, can precipitate from bleaching effluent about 75% of adsorbable organic chlorine (AOX), 59% of chemical oxygen demand (COD) and 80% of colour. These mixtures contained less polyimine in comparison to when polyimine was used aline thus saving material costs. After removal of chloroorganics of high molecular mass by precipitation growth of microorganisms in SBE was facilitated. The supernatant of the treated SBE supplemented with glucose and ammonium sulfate supported active growth of fungi from different genera, particularly from Aspergillus spp., Penicillium spp., Basidiomycetes, Aureobasidium. The fungi tested showed appreciable degradation activity regarding monochlorophenols,as well as additional reduction of AOX. During the growth in the treated SBE, Aureobasidiumpullulans decreased the content of AOX remaining after precipitation, and at the same time synthesized and excreted in a surrounding media exopolysaccharides. Pullulan, synthesized in appreciable level by Aureobasidium sp, could easily be isolated from the media. Isolated exopolysaccharides did not contain organochlorine. Fungal polysaccharides synthesized in SBE might be considered as an additional benefit that eventually will be able to reduce further the running costs of the SBE treatment.
14
Cohen, Michael F., Xiang Y. Han, and Mark Mazzola. "Molecular and physiological comparison ofAzospirillumspp. isolated fromRhizoctonia solanimycelia, wheat rhizosphere, and human skin wounds." Canadian Journal of Microbiology 50, no. 4 (April 1, 2004): 291–97. http://dx.doi.org/10.1139/w04-007.
Повний текст джерелаАнотація:
Four phenotypically similar bacterial strains isolated from fungal, plant, and human sources were identified as Azospirillum species. Strains RC1 and LOD4 were isolated from the mycelium of the apple root pathogen Rhizoctonia solani AG 5 and from the rhizosphere of wheat grown in apple orchard soil, respectively. Strains C610 and F4626 isolated from human wounds were previously misclassified as Roseomonas genomospecies 3 and 6. All four strains demonstrated close similarities in 16S rRNA gene sequences, having [Formula: see text]97% identity to Azospirillum brasilense type strain ATCC 29145 and <90% identity to Roseomonas gilardii, the Roseomonas type strain. Extensive phenotypic similarities among the four strains included the ability of free-living cells to fix N2. Cells of strains RC1, LOD4, and C610 but not of strain F4626 could be induced to flocculate by incubation with 10 mmol·L–1glycerol or fructose in medium containing 0.5 mmol·L–1NO3–. Our results indicate a wide range of potential sources for Azospirillum spp. with the isolation of Azospirillum spp. from human wounds warranting further investigation.Key words: Azospirillum brasilense, Roseomonas fauriae, flocculation, Rhizoctonia solani.
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Paździor, Katarzyna, Julita Wrębiak, and Stanisław Ledakowicz. "Treatment of Industrial Textile Wastewater in Biological Aerated Filters – Microbial Diversity Analysis." Fibres and Textiles in Eastern Europe 28, no. 1(139) (February 29, 2020): 106–14. http://dx.doi.org/10.5604/01.3001.0013.5865.
Повний текст джерелаАнотація:
Investigated herein was the biodegradation of highly contaminated textile wastewater on a laboratory scale, with biological aerobic filters as a single treatment and in combination with the coagulation/flocculation process. Among the three support materials tested (Intalox saddles, ceramsite and beach shavings), the highest organic carbon compound removals (above 60% measured as COD and TOC) and steady operation were obtained for ceramsite. Effective and stable biological treatment was possible thanks to the development of biofilm of high bacterial and fungal diversity. The biodiversity of microflora was estimated on the basis of metagenomic analysis. The coagulation process with PAX 18 was effective in total phosphorus depletion (94%), while the coagulant Epoly CRD enabled up to 99% colour removal. The best results were obtained after the combined treatment, in which biodegradation was followed by coagulation (PAX 18). Such a combination enabled the removal of 98% of BOD5, 87% of COD, 88% of TOC, 48% of the total nitrogen, 98% of the total phosphorus, 98% of toxicity (towards Vibrio fisheri) and above 81% of colour.
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Mir-Tutusaus, J. A., E. Parladé, M. Llorca, M. Villagrasa, D. Barceló, S. Rodriguez-Mozaz, M. Martinez-Alonso, N. Gaju, G. Caminal, and M. Sarrà. "Pharmaceuticals removal and microbial community assessment in a continuous fungal treatment of non-sterile real hospital wastewater after a coagulation-flocculation pretreatment." Water Research 116 (June 2017): 65–75. http://dx.doi.org/10.1016/j.watres.2017.03.005.
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Journal, Baghdad Science. "Microalgae Chlorella Vulgaris Harvesting Via Co-Pelletization with Filamentous Fungus." Baghdad Science Journal 15, no. 1 (March 4, 2018): 31–36. http://dx.doi.org/10.21123/bsj.15.1.31-36.
Повний текст джерелаАнотація:
The objective of this study was to progress another method for coagulation/flocculation of the microalga Chlorella vulgaris via pellet-forming of the fungal species Aspergillus niger which was isolated from municipal wastewater mud and the facultative heterotrophic microalga "C.vulgaris was used. The main factors studies were spore inoculums, organic carbon concentration in medium as well as pH variation which had considerably positive effects on microalgae/fungi co-pelletization formation. The process parameters are an inoculum1×104 spores/ML, 15 g/l sucrose as carbon source and pH ranged from 5 - 7.0 were found optimal for efficient microalgae/fungi co-pelletization formation. For autotrophic growth, when pH of culture broth was adjusted to 5.0 -7.0 with organic carbon addition (15 g/L sucrose), almost complete harvesting efficiency of the microalga was achieved. Furthermore, it was observed that diameter and the concentration of microalgae/fungi pellets were pretentious by the shaker rotation. The new harvesting technology established in this study will decrease the microalga harvesting cost and will be possible to adapt this technique to all microalgal species as an alternative to other old-style harvesting approaches.
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Garcia-Sanchez, Angela M., Bernardino Machado-Moreira, Mário Freire, Ricardo Santos, Sílvia Monteiro, Diamantino Dias, Orquídia Neves, Amélia Dionísio, and Ana Z. Miller. "Characterization of Microbial Communities Associated with Ceramic Raw Materials as Potential Contributors for the Improvement of Ceramic Rheological Properties." Minerals 9, no. 5 (May 23, 2019): 316. http://dx.doi.org/10.3390/min9050316.
Повний текст джерелаАнотація:
Technical ceramics are being widely employed in the electric power, medical and engineering industries because of their thermal and mechanical properties, as well as their high resistance qualities. The manufacture of technical ceramic components involves complex processes, including milling and stirring of raw materials in aqueous solutions, spray drying and dry pressing. In general, the spray-dried powders exhibit an important degree of variability in their performance when subjected to dry-pressing, which affects the efficiency of the manufacturing process. Commercial additives, such as deflocculants, biocides, antifoam agents, binders, lubricants and plasticizers are thus applied to ceramic slips. Several bacterial and fungal species naturally occurring in ceramic raw materials, such as Sphingomonas, Aspergillus and Aureobasidium, are known to produce exopolysaccharides. These extracellular polymeric substances (EPS) may confer unique and potentially interesting properties on ceramic slips, including viscosity control, gelation, and flocculation. In this study, the microbial communities present in clay raw materials were identified by both culture methods and DNA-based analyses to select potential EPS producers based on the scientific literature for further assays based on the use of EPS for enhancing the performance of technical ceramics. Potential exopolysaccharide producers were identified in all samples, such as Sphingomonas sp., Pseudomonas xanthomarina, P. stutzeri, P. koreensis, Acinetobacter lwoffi, Bacillus altitudinis and Micrococcus luteus, among bacteria. Five fungi (Penicillium citrinum, Aspergillus niger, Fusarium oxysporum, Acremonium persicinum and Rhodotorula mucilaginosa) were also identified as potential EPS producers.
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Hsu, Po-Chen, Chun-Cheih Chao, Cheng-Yao Yang, Ya-Ling Ye, Fu-Chen Liu, Yung-Jen Chuang, and Chung-Yu Lan. "Diverse Hap43-Independent Functions of the Candida albicans CCAAT-Binding Complex." Eukaryotic Cell 12, no. 6 (March 29, 2013): 804–15. http://dx.doi.org/10.1128/ec.00014-13.
Повний текст джерелаАнотація:
ABSTRACTThe CCAAT motif is ubiquitous in promoters of eukaryotic genomes. The CCAAT-binding complex (CBC) is conserved across a wide range of organisms, specifically recognizes the CCAAT motif, and modulates transcription directly or in cooperation with other transcription factors. InCandida albicans, CBC is known to interact with the repressor Hap43 to negatively regulate iron utilization genes in response to iron deprivation. However, the extent of additional functions of CBC is unclear. In this study, we explored new roles of CBC inC. albicansand found that CBC pleiotropically regulates many virulence traitsin vitro, including negative control of genes responsible for ribosome biogenesis and translation and positive regulation of low-nitrogen-induced filamentation. In addition,C. albicansCBC is involved in utilization of host proteins as nitrogen sources and in repression of cellular flocculation and adhesin gene expression. Moreover, our epistasis analyses suggest that CBC acts as a downstream effector of Rhb1-TOR signaling and controls low-nitrogen-induced filamentation via the Mep2-Ras1-protein kinase A (PKA)/mitogen-activated protein kinase (MAPK) pathway. Importantly, the phenotypes identified here are all independent of Hap43. Finally, deletion of genes encoding CBC components slightly attenuatedC. albicansvirulence in both zebrafish and murine models of infection. Our results thus highlight new roles ofC. albicansCBC in regulating multiple virulence traits in response to environmental perturbations and, finally, suggest potential targets for antifungal therapies as well as extending our understanding of the pathogenesis of other fungal pathogens.
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Fellah, Maroua, MD ZAHANGIR ALAM, ABDULLAH AL-MAMUN, NASSERLDEEN AHMED KHABBASHI, NURUL SAKINAH ENGLIMAN, and SONIA HADJ ARAB. "Effect of the lignocellulolytic substrates and fermentation process parameters on myco-coagulant production for water treatment." IIUM Engineering Journal 24, no. 1 (January 4, 2023): 13–26. http://dx.doi.org/10.31436/iiumej.v24i1.2400.
Повний текст джерелаАнотація:
In the present research, a fungal strain was used to produce a myco-coagulant via solid-state bioconversion to reduce water turbidity. The production of myco-coagulant was achieved using several low-cost lignocellulolytic substrates, namely coco peat, sawdust, palm kernel cake, and rice bran as sources of carbon and nitrogen. This research involves the study of both the effect of lignocellulolytic substrates and the parameters involved in the fermentation process for myco-coagulant production. Coco peat was chosen as a suitable lignocellulolytic substrate to serve as a carbon source for producing myco-coagulant, potentially reducing the turbidity by 84.6% from the kaolin suspension. Sawdust, palm kernel cake, and rice bran showed 33.06%, 30.18, and 21.18 %, respectively. Furthermore, a statistical approach to the Plackett-Burman design was conducted to evaluate the significant parameters that affect the production of myco-coagulant. Eleven fermentation process parameters were selected: concentration of coco peat (2- 4 %), incubation time (5-9 days), temperature (25-35 °C), pH (5-9), glucose (0-2 %), malt extract (1-2 %), yeast extract (0-2%), wheat flour (0-2 %), ammonium sulfate (0-1 %), inoculum size (1-3 %) and potassium dihydrogen phosphate (0-0.5 %). The selected variables were assessed through statistical analysis (main effects) based on their significance. Based on the main effect of each variable on flocculation activity, three variables, namely glucose, malt extract, and pH influenced high levels. On the other hand, the remaining eight variables did not significantly affect the production of myco-coagulant. Furthermore, a deeper study was conducted to further optimize the three effective variables involved in the fermentation process to evaluate these factors' influence on flocculation activity. ABSTRAK: Penyelidikan ini adalah berkenaan strain fungus yang digunakan bagi menghasilkan miko-koagulan melalui penukaran-bio berkeadaan pepejal bagi mengurangkan kekeruhan air. Miko-koagulan dihasilkan dengan menggunakan beberapa substrat lignoselulolitik berkos rendah, iaitu habuk kelapa, habuk papan, hampas kelapa sawit, dan dedak padi sebagai sumber karbon dan nitrogen. Penyelidikan ini mengkaji kesan substrat lignoselulolitik dan faktor-faktor yang terlibat dalam proses fermentasi bagi menghasilkan miko-koagulan. Habuk kelapa dipilih sebagai substrat lignoselulolitik yang sesuai berfungsi sebagai sumber karbon dalam menghasilkan miko-koagulan, berpotensi mengurangkan kekeruhan sebanyak 84.6% daripada ampaian kaolin. Sebaliknya, habuk papan, hampas kelapa sawit, dan dedak padi menunjukkan 33.06%, 30.18, dan 21.18 %, masing-masing. Tambahan pula, pendekatan statistik ke atas reka bentuk Plackett-Burman telah dijalankan bagi menilai parameter penting yang mempengaruhi penghasilan miko-koagulan. Sebelas parameter proses penapaian telah dipilih: kepekatan habuk kelapa (2- 4 %), masa pengeraman (5-9 hari), suhu (25-35 C), pH (5-9), glukosa (0-2 %), ekstrak malt (1-2), tepung gandum (0-2 %), ammonium sulfat (0-1%), saiz inokulum (1-3 %) dan Kalium dihidrogen fosfat (0-0.5 %). Pemboleh ubah yang dipilih dinilai melalui analisis statistik berdasarkan kepentingannya. Berdasarkan kesan utama setiap pemboleh ubah terhadap aktiviti penggumpalan, tiga pemboleh ubah ini adalah glukosa, ekstrak malt, dan pH yang memberi kesan tertinggi. Sebaliknya, lapan pemboleh ubah lain tidak mempengaruhi penghasilan miko-koagulan dengan ketara. Tambahan lagi, kajian yang lebih mendalam telah dijalankan bagi membaiki tiga pemboleh ubah utama yang terlibat dalam proses fermentasi bagi menilai kesan yang mempengaruhi aktiviti penggumpalan.
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Fellah, M., M. Z. Alam, A. Al-Mamun, N. A. Kabbashi, and N. S. B. Engliman. "Evaluation of solid-state production of myco-coagulant using various lignocellulosic media to reduce water turbidity." IOP Conference Series: Materials Science and Engineering 1192, no. 1 (November 1, 2021): 012022. http://dx.doi.org/10.1088/1757-899x/1192/1/012022.
Повний текст джерелаАнотація:
Abstract High turbidity and suspended solids (SS) are among the significant issues that affect rivers due to the wastewater discharge, terrain condition, land cover, rainfall, agriculture, and other development activities. Chemical flocculants such as polyacrylamide and aluminum sulfate are widely employed for agro-industrial wastewater treatment. However, excessive use of chemical coagulants is harmful to human beings and the environment. Therefore, efficient and economically viable bio-coagulants from renewable biological sources is highly sought after. Myco-coagulant (My-coag) is an organic coagulant produced by fungi that are biodegradable and environmentally friendly. This research aimed to evaluate My-coag solid-state production from locally isolated fungal strains using various lignocellulosic media. The fungus was grown on different lignocellulosic substrates such as cocopeat, sawdust, rice bran, and palm kernel cake for 7 days with a pH of 7.0 at 30 °C. My-coag was extracted from the fungal culture using an aqueous buffer solution of pH 7. The fungal growth rate and dry mass were the highest on cocopeat supplement which was about 1.4 g of dry weight. My-coag extracted from the cocopeat showed good flocculating properties in kaolin suspension with the removal of 96.7% turbidity compared to other substrates such as sawdust, palm kernel cake, and rice bran with the removal of 53.7, 19.6, and 11%, respectively. It is expected that further optimization of this process parameters will lead to the efficient removal of turbidity and solids from water and wastewater to move forward in green technology for sustainable growth in the “Clean Water and Sanitation Sector” and protection of the environment too.
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Chan, Cho X. J., Sofiane El-Kirat-Chatel, Ivor G. Joseph, Desmond N. Jackson, Caleen B. Ramsook, Yves F. Dufrêne, and Peter N. Lipke. "Force Sensitivity in Saccharomyces cerevisiae Flocculins." mSphere 1, no. 4 (August 17, 2016). http://dx.doi.org/10.1128/msphere.00128-16.
Повний текст джерелаАнотація:
ABSTRACT The Saccharomyces cerevisiae flocculins mediate the formation of cellular aggregates and biofilm-like mats, useful in clearing yeast from fermentations. An important property of fungal adhesion proteins, including flocculins, is the ability to form catch bonds, i.e., bonds that strengthen under tension. This strengthening is based, at least in part, on increased avidity of binding due to clustering of adhesins in cell surface nanodomains. This clustering depends on amyloid-like β-aggregation of short amino acid sequences in the adhesins. In Candida albicans adhesin Als5, shear stress from vortex mixing can unfold part of the protein to expose aggregation-prone sequences, and then adhesins aggregate into nanodomains. We therefore tested whether shear stress from mixing can increase flocculation activity by potentiating similar protein remodeling and aggregation in the flocculins. The results demonstrate the applicability of the Als adhesin model and provide a rational framework for the enhancement or inhibition of flocculation in industrial applications. Many fungal adhesins have short, β-aggregation-prone sequences that play important functional roles, and in the Candida albicans adhesin Als5p, these sequences cluster the adhesins after exposure to shear force. Here, we report that Saccharomyces cerevisiae flocculins Flo11p and Flo1p have similar β-aggregation-prone sequences and are similarly stimulated by shear force, despite being nonhomologous. Shear from vortex mixing induced the formation of small flocs in cells expressing either adhesin. After the addition of Ca2+, yeast cells from vortex-sheared populations showed greatly enhanced flocculation and displayed more pronounced thioflavin-bright surface nanodomains. At high concentrations, amyloidophilic dyes inhibited Flo1p- and Flo11p-mediated agar invasion and the shear-induced increase in flocculation. Consistent with these results, atomic force microscopy of Flo11p showed successive force-distance peaks characteristic of sequentially unfolding tandem repeat domains, like Flo1p and Als5p. Flo11p-expressing cells bound together through homophilic interactions with adhesion forces of up to 700 pN and rupture lengths of up to 600 nm. These results are consistent with the potentiation of yeast flocculation by shear-induced formation of high-avidity domains of clustered adhesins at the cell surface, similar to the activation of Candida albicans adhesin Als5p. Thus, yeast adhesins from three independent gene families use similar force-dependent interactions to drive cell adhesion. IMPORTANCE The Saccharomyces cerevisiae flocculins mediate the formation of cellular aggregates and biofilm-like mats, useful in clearing yeast from fermentations. An important property of fungal adhesion proteins, including flocculins, is the ability to form catch bonds, i.e., bonds that strengthen under tension. This strengthening is based, at least in part, on increased avidity of binding due to clustering of adhesins in cell surface nanodomains. This clustering depends on amyloid-like β-aggregation of short amino acid sequences in the adhesins. In Candida albicans adhesin Als5, shear stress from vortex mixing can unfold part of the protein to expose aggregation-prone sequences, and then adhesins aggregate into nanodomains. We therefore tested whether shear stress from mixing can increase flocculation activity by potentiating similar protein remodeling and aggregation in the flocculins. The results demonstrate the applicability of the Als adhesin model and provide a rational framework for the enhancement or inhibition of flocculation in industrial applications.
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Salinas, Francisco, Vicente Rojas, Verónica Delgado, Javiera López, Eduardo Agosin, and Luis F. Larrondo. "Fungal Light-Oxygen-Voltage Domains for Optogenetic Control of Gene Expression and Flocculation in Yeast." mBio 9, no. 4 (July 31, 2018). http://dx.doi.org/10.1128/mbio.00626-18.
Повний текст джерелаАнотація:
ABSTRACT Optogenetic switches permit accurate control of gene expression upon light stimulation. These synthetic switches have become a powerful tool for gene regulation, allowing modulation of customized phenotypes, overcoming the obstacles of chemical inducers, and replacing their use by an inexpensive resource: light. In this work, we implemented FUN-LOV, an optogenetic switch based on the photon-regulated interaction of WC-1 and VVD, two LOV (light-oxygen-voltage) blue-light photoreceptors from the fungus Neurospora crassa. When tested in yeast, FUN-LOV yields light-controlled gene expression with exquisite temporal resolution and a broad dynamic range of over 1,300-fold, as measured by a luciferase reporter. We also tested the FUN-LOV switch for heterologous protein expression in Saccharomyces cerevisiae, where Western blot analysis confirmed strong induction upon light stimulation, surpassing by 2.5 times the levels achieved with a classic GAL4/galactose chemical-inducible system. Additionally, we utilized FUN-LOV to control the ability of yeast cells to flocculate. Light-controlled expression of the flocculin-encoding gene FLO1, by the FUN-LOV switch, yielded flocculation in light (FIL), whereas the light-controlled expression of the corepressor TUP1 provided flocculation in darkness (FID). Altogether, the results reveal the potential of the FUN-LOV optogenetic switch to control two biotechnologically relevant phenotypes such as heterologous protein expression and flocculation, paving the road for the engineering of new yeast strains for industrial applications. Importantly, FUN-LOV’s ability to accurately manipulate gene expression, with a high temporal dynamic range, can be exploited in the analysis of diverse biological processes in various organisms. IMPORTANCE Optogenetic switches are molecular devices which allow the control of different cellular processes by light, such as gene expression, providing a versatile alternative to chemical inducers. Here, we report a novel optogenetic switch (FUN-LOV) based on the LOV domain interaction of two blue-light photoreceptors (WC-1 and VVD) from the fungus N. crassa. In yeast cells, FUN-LOV allowed tight regulation of gene expression, with low background in darkness and a highly dynamic and potent control by light. We used FUN-LOV to optogenetically manipulate, in yeast, two biotechnologically relevant phenotypes, heterologous protein expression and flocculation, resulting in strains with potential industrial applications. Importantly, FUN-LOV can be implemented in diverse biological platforms to orthogonally control a multitude of cellular processes.
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Speers. "Assessing the Effect of Fungal Infection of Barley and Malt on Premature Yeast Flocculation." Journal of the American Society of Brewing Chemists, 2014. http://dx.doi.org/10.1094/asbcj-2014-0204-01.
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Nie, Yong, Zimin Wang, Wei Wang, Zhengyu Zhou, Yanli Kong, and Jiangya Ma. "Bio-flocculation of Microcystis aeruginosa by using fungal pellets of Aspergillus oryzae: Performance and mechanism." Journal of Hazardous Materials, July 2022, 129606. http://dx.doi.org/10.1016/j.jhazmat.2022.129606.
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Nie, Yong, Zimin Wang, Wei Wang, Zhengyu Zhou, Yanli Kong, and Jiangya Ma. "Bio-Flocculation of Microcystis Aeruginosa by Using Fungal Pellets of Aspergillus Oryzae: Performance and Mechanism." SSRN Electronic Journal, 2022. http://dx.doi.org/10.2139/ssrn.4105017.
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Saguez, Cyril, David Viterbo, Stéphane Descorps-Declère, Brendan P. Cormack, Bernard Dujon, and Guy-Franck Richard. "Functional variability in adhesion and flocculation of yeast megasatellite genes." Genetics, March 11, 2022. http://dx.doi.org/10.1093/genetics/iyac042.
Повний текст джерелаАнотація:
Abstract Megasatellites are large tandem repeats found in all fungal genomes but especially abundant in the opportunistic pathogen Candida glabrata. They are encoded in genes involved in cell–cell interactions, either between yeasts or between yeast and human cells. In the present work, we have been using an iterative genetic system to delete several Candida glabrata megasatellite-containing genes and found that 2 of them were positively involved in adhesion to epithelial cells, whereas 3 genes negatively controlled adhesion. Two of the latter, CAGL0B05061g or CAGL0A04851g, were also negative regulators of yeast-to-yeast adhesion, making them central players in controlling Candida glabrata adherence properties. Using a series of synthetic Saccharomyces cerevisiae strains in which the FLO1 megasatellite was replaced by other tandem repeats of similar length but different sequences, we showed that the capacity of a strain to flocculate in liquid culture was unrelated to its capacity to adhere to epithelial cells or to invade agar. Finally, to understand how megasatellites were initially created and subsequently expanded, an experimental evolution system was set up, in which modified yeast strains containing different megasatellite seeds were grown in bioreactors for more than 200 generations and selected for their ability to sediment at the bottom of the culture tube. Several flocculation-positive mutants were isolated. Functionally relevant mutations included general transcription factors as well as a 230-kbp segmental duplication.
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Ma, Yan, Ying Ji, Wen Cen, Zusha Qiao, Yan Gao, Lu He, and Wenli Feng. "Assessment of the Clinical Diagnosis of Onychomycosis by Dermoscopy." Frontiers in Surgery 9 (March 16, 2022). http://dx.doi.org/10.3389/fsurg.2022.854632.
Повний текст джерелаАнотація:
BackgroundAs a common clinical superficial fungal infection, the diagnosis of onychomycosis relies on clinical features, traditional KOH direct microscopy and fungal culture. In recent years, dermoscopy has been widely used in the diagnosis and treatment of infectious diseases and has provided new options for the diagnosis of onychomycosis.ObjectiveTo evaluate the value of dermoscopy in the clinical diagnosis of onychomycosis and to explore the relationship between each clinical subtype and the dermoscopic pattern.MethodsA retrospective study of 114 cases of clinically suspected onychomycosis was conducted to compare the differences between dermoscopy and fungal pathogenic examination (microscopy and culture) in the diagnostic sensitivity of onychomycosis and to analyze the relationship between nine common dermoscopic modalities and clinical subtypes of onychomycosis.ResultsAmong the 114 proposed patients, 87 nails with positive fluorescent staining microscopy and/or positive fungal cultures were diagnosed as onychomycosis. The sensitivity and specificity of dermatoscopy, using the mycological findings as a reference, were 86.21 and 33.33%, respectively. The incidence of common dermatoscopic patterns in the 87 nails with confirmed onychomycosis was as follows: white flocculation in 76 cases (87.35%), longitudinal nail pattern in 72 cases (82.76%), jagged changes in the distal nail plate in 69 cases (79.31%) and yellow staining in 46 cases (52.87%), these four patterns were more commonly seen in the distal lateral subungual onychomycosis and total dystrophic onychomycosis, but there was no statistical difference in the positive dermatoscopic pattern between these two types (P > 0.05).ConclusionDermoscopy can be an important aid in the diagnosis of onychomycosis, especially when fungal microscopy or culture is not appropriate, but this method is still not a substitute for fungal microscopy and culture.
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Nie, Yong, Zimin Wang, Wei Wang, Zhengyu Zhou, Yanli Kong, and Jiangya Ma. "Bio-Flocculation of Microcystis Aeruginosa by Using Fungal Pellets of Aspergillus Oryzae: Harvesting Performance and Mechanism." SSRN Electronic Journal, 2022. http://dx.doi.org/10.2139/ssrn.4084274.
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Qin, Qingqing, Jia Liu, Shumin Hu, Junhong Yu, Lei Zhang, Shuxia Huang, Mei Yang, and Lushan Wang. "Exploring Fungal Species Diversity in the Premature Yeast Flocculation (PYF) of Barley Malt Using Deep Sequencing." Journal of the American Society of Brewing Chemists, March 2, 2022, 1–7. http://dx.doi.org/10.1080/03610470.2021.2025329.
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Miranda, Isabel, Ana Silva-Dias, Rita Rocha, Rita Teixeira-Santos, Carolina Coelho, Teresa Gonçalves, Manuel A. S. Santos, et al. "Candida albicans CUG Mistranslation Is a Mechanism To Create Cell Surface Variation." mBio 4, no. 4 (June 25, 2013). http://dx.doi.org/10.1128/mbio.00285-13.
Повний текст джерелаАнотація:
ABSTRACT In the human fungal pathogen Candida albicans, the CUG codon is translated 97% of the time as serine and 3% of the time as leucine, which potentially originates an array of proteins resulting from the translation of a single gene. Genes encoding cell surface proteins are enriched in CUG codons; thus, CUG mistranslation may influence the interactions of the organism with the host. To investigate this, we compared a C. albicans strain that misincorporates 28% of leucine at CUGs with a wild-type parental strain. The first strain displayed increased adherence to inert and host molecules. In addition, it was less susceptible to phagocytosis by murine macrophages, probably due to reduced exposure of cell surface β-glucans. To prove that these phenotypes occurred due to serine/leucine exchange, the C. albicans adhesin and invasin ALS3 was expressed in Saccharomyces cerevisiae in its two natural isoforms (Als3p-Leu and Als3p-Ser). The cells with heterologous expression of Als3p-Leu showed increased adherence to host substrates and flocculation. We propose that CUG mistranslation has been maintained during the evolution of C. albicans due to its potential to generate cell surface variability, which significantly alters fungus-host interactions. IMPORTANCE The translation of genetic information into proteins is a highly accurate cellular process. In the human fungal pathogen Candida albicans, a unique mistranslation event involving the CUG codon occurs. The CUG codon is mainly translated as serine but can also be translated as leucine. Leucine and serine are two biochemically distinct amino acids, hydrophobic and hydrophilic, respectively. The increased rate of leucine incorporation at CUG decoding triggers C. albicans virulence attributes, such as morphogenesis, phenotypic switching, and adhesion. Here, we show that CUG mistranslation masks the fungal cell wall molecule β-glucan that is normally recognized by the host immune system, delaying its response. Furthermore, we demonstrate that two different proteins of the adhesin Als3 generated by CUG mistranslation confer increased hydrophobicity and adhesion ability on yeast cells. Thus, CUG mistranslation functions as a mechanism to create protein diversity with differential activities, constituting an advantage for a mainly asexual microorganism. This could explain its preservation during evolution.
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Olusola-makinde, Olubukola, Michael Bayode, and Eniola Dawodu. "BIO-FLOCCULATION AND ANTIMICROBIAL ACTIVITIES OF POWDERED MORINGA OLEIFERA (LAM) SEEDS AND ALUM ON DOMESTIC WASTEWATER MICROBIAL CONSORTIA." Bacterial Empire, May 25, 2021, e267. http://dx.doi.org/10.36547/be.267.
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Introduction: Moringa oleifera seed is a bio-flocculant liable to purify water and verified to be one of the generally efficient prime coagulants for water treatment. M. oleifera seeds also have the potentials to eliminate a broad variety of bacteria, including Escherichia coli, Bacillus subtilis, B. cereus, Pseudomonas aeruginosa and Enterobacter ludwigii, from domestic wastewater. Objective: The comparative bio-flocculating ability and antimicrobial activities of powdered Moringa oleifera seeds and alum for the treatment of domestic wastewater from a university student’ hostels were explored. Methods: Collection of wastewater samples, physicochemical analysis of wastewater samples and treatment of the wastewater samples with powdered M. oleifera seeds and alum were conducted using standard techniques. Enumeration and identification of bacteria using biochemical depiction and (16S RNA) with fungi after treatment were employed via standard protocols. Results: The optimum pH obtained using powdered M. oleifera seeds was 6.00 – 7.38 and in line with the recommended WHO standard. This study revealed that the bacterial count in wastewater samples of Jibowu and Abiola hostels after treatment with 2g of powdered M. oleifera seeds and 6g of alum was high (199.67±0.89 CFU/ml); low (26.00±0.57 CFU/ml) for powdered M. oleifera seeds and high (87.00±0.57 CFU/ml); low (6.33±0.57 CFU/ml) for alum respectively. The fungal count of the wastewater samples for Akindeko and Jibowu hostels after treatment with 2g of powdered M. oleifera seeds and 6g of alum was high (26.00±0.57 Sfu/ml); low (5.00±0.57 Sfu/ml) for powdered M. oleifera seeds and high (19.00±0.58 Sfu/ml); low (2.00±0.57 Sfu/ml) for alum respectively. Escherichia coli, Bacillus subtilis with NCBI-certified B. cereus mkbk1, Pseudomonas aeruginosa mkbk 2 and Enterobacter ludwigii mkbk 3 were isolated from the wastewater samples. Conclusion: The findings of this study suggest that the bio-flocculating ability of powdered M. oleifera seeds accentuated better antimicrobial efficacy of M. oleifera over alum as a proviso to the blend of powdered M. oleifera seeds and alum for the treatment of domestic wastewaters.
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Flanagan, Peter R., Ning-Ning Liu, Darren J. Fitzpatrick, Karsten Hokamp, Julia R. Köhler, and Gary P. Moran. "The Candida albicans TOR-Activating GTPases Gtr1 and Rhb1 Coregulate Starvation Responses and Biofilm Formation." mSphere 2, no. 6 (November 15, 2017). http://dx.doi.org/10.1128/msphere.00477-17.
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ABSTRACT Candida albicans is the major fungal pathogen of humans and is responsible for a wide range of infections, including life-threatening systemic infections in susceptible hosts. Target of rapamycin complex 1 (TORC1) is an essential regulator of metabolism in this fungus, and components of this complex are under increased investigation as targets for new antifungal drugs. The present study characterized the role of GTR1, encoding a putative GTPase, in TORC1 activation. This study shows that GTR1 encodes a protein required for activation of TORC1 activity in response to amino acids and regulation of nitrogen starvation responses. GTR1 mutants show increased cell-cell adhesion and biofilm formation and increased expression of genes involved in these processes. This study demonstrates that starvation responses and biofilm formation are coregulated by GTR1 and suggests that these responses are linked to compete with the microbiome for space and nutrients. Target of rapamycin complex 1 (TORC1) is an essential regulator of metabolism in eukaryotic cells and in the fungal pathogen Candida albicans regulates morphogenesis and nitrogen acquisition. Gtr1 encodes a highly conserved GTPase that in Saccharomyces cerevisiae regulates nitrogen sensing and TORC1 activation. Here, we characterize the role of C. albicans GTR1 in TORC1 activation and compare it with the previously characterized GTPase Rhb1. A homozygous gtr1/gtr1 mutant exhibited impaired TORC1-mediated phosphorylation of ribosomal protein S6 and increased susceptibility to rapamycin. Overexpression of GTR1 impaired nitrogen starvation-induced filamentous growth, MEP2 expression, and growth in bovine serum albumin as the sole nitrogen source. Both GTR1 and RHB1 were shown to regulate genes involved in ribosome biogenesis, amino acid biosynthesis, and expression of biofilm growth-induced genes. The rhb1/rhb1 mutant exhibited a different pattern of expression of Sko1-regulated genes and increased susceptibility to Congo red and calcofluor white. The homozygous gtr1/gtr1 mutant exhibited enhanced flocculation phenotypes and, similar to the rhb1/rhb1 mutant, exhibited enhanced biofilm formation on plastic surfaces. In summary, Gtr1 and Rhb1 link nutrient sensing and biofilm formation and this connectivity may have evolved to enhance the competitiveness of C. albicans in niches where there is intense competition with other microbes for space and nutrients. IMPORTANCE Candida albicans is the major fungal pathogen of humans and is responsible for a wide range of infections, including life-threatening systemic infections in susceptible hosts. Target of rapamycin complex 1 (TORC1) is an essential regulator of metabolism in this fungus, and components of this complex are under increased investigation as targets for new antifungal drugs. The present study characterized the role of GTR1, encoding a putative GTPase, in TORC1 activation. This study shows that GTR1 encodes a protein required for activation of TORC1 activity in response to amino acids and regulation of nitrogen starvation responses. GTR1 mutants show increased cell-cell adhesion and biofilm formation and increased expression of genes involved in these processes. This study demonstrates that starvation responses and biofilm formation are coregulated by GTR1 and suggests that these responses are linked to compete with the microbiome for space and nutrients.
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David, O. M., O. A. Oluwole, O. E. Ayodele, and T. Lasisi. "Characterisation of Fungal Bioflocculants and Its Application in Water Treatment." Current Journal of Applied Science and Technology, April 26, 2019, 1–9. http://dx.doi.org/10.9734/cjast/2019/v34i630159.
Повний текст джерелаАнотація:
Bioflocculants of microbial origin have the advantage of being safe, biodegradable and harmless to the environment. Production of bioflocculant by two fungi isolates and the factors affecting its production were investigated in this study. Primary screening of fungi for the production of bioflocculants, efficiencies and conditions for the optimum production of the bioflocculants were determined using standard microbiological and chemical methods. Aspergillus flavus MCB 271 and Aspergillus niger MCBF 08 were the best bioflocculant producers among the fourteen fungal isolates screened. Aspergillus flavus optimally produced bioflocculant with glucose and peptone as sole carbon and nitrogen sources respectively. Calcium ions (Ca2+) at 78.4% served as best cation sources for bioflocculant production with optimal pH of 7 and temperature of 40°C. Aspergillus niger MCBF 08 produced bioflocculant optimally when the media had peptone as a nitrogen source and maltose as a sole carbon source. The two species achieved the maximum flocculating activity of 97% (A. flavus MCBF 271) and 86% (A. niger MCBF 08) at pH values of 7 on the 3rd day of the study and caused a reduction in bacterial load of the wastewater samples by 58.73% and 60.85% respectively. These bioflocculants are thus potential replacement for synthetic flocculants conventionally used for wastewater treatment.