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Pesquisa : B01.300.107.795.905 [Categoria DeCS]
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  1 / 22 MEDLINE  
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[PMID]:26615855
[Au] Autor:Yeo AY; Toh MZ; Liu SQ
[Ad] Endereço:1 Food Science and Technology Programme, Department of Chemistry, 3 Science Drive 3, National University of Singapore, Singapore 117543, Singapore.
[Ti] Título:Enhancement of bifidobacteria survival by Williopsis saturnus var. saturnus in milk.
[So] Source:Benef Microbes;7(1):135-144, 2016 Feb.
[Is] ISSN:1876-2891
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The viability of three strains of probiotic Bifidobacterium lactis that were inoculated into UHT milk was examined with and without the presence of the yeast, Williopsis saturnus var. saturnus NCYC 22, in polypropylene tubes at 30 C. The B. lactis viable cell count for strains HN019 and BB-12 remained above 6.0 Log cfu/ml, while strain B94 had 5.7 Log cfu/ml after six weeks of incubation in the presence of the co-inoculated yeast. Incubating the bifidus milk without added yeast under anaerobic condition did not improve the survival of B. lactis HN019, indicating that oxygen removal may not be responsible for W. saturnus NCYC 22's viability enhancing property. The addition of yeast supernatant or non-viable yeast also did not show any stabilising effects, suggesting that physical contact and/or interaction between viable W. saturnus and B. lactis plays an important role in sustaining the viability of the probiotic. W. saturnus NCYC 22 could increase the survival of B. lactis in bifidus milk under ambient temperature regardless of the initial concentration of yeast cells inoculated due to yeast growth. This study demonstrated the viability enhancing effect of viable W. saturnus NCYC 22 on B. lactis HN019, which could help towards extending the shelf-life of dairy beverages containing probiotic bifidobacteria.
[Mh] Termos MeSH primário: Bifidobacterium/fisiologia
Leite/microbiologia
Probióticos
Williopsis/fisiologia
[Mh] Termos MeSH secundário: Aerobiose
Anaerobiose
Animais
Bifidobacterium/crescimento & desenvolvimento
Armazenamento de Alimentos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170208
[Lr] Data última revisão:
170208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151201
[St] Status:MEDLINE
[do] DOI:10.3920/BM2015.0012


  2 / 22 MEDLINE  
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[PMID]:23862159
[Au] Autor:Yilmaztekin M; Cabaroglu T; Erten H
[Ad] Endereço:Inonu University, Faculty of Engineering, Department of Food Engineering, 44280 Malatya, Turkey. murat.yilmaztekin@inonu.edu.tr
[Ti] Título:Effects of fermentation temperature and aeration on production of natural isoamyl acetate by Williopsis saturnus var. saturnus.
[So] Source:Biomed Res Int;2013:870802, 2013.
[Is] ISSN:2314-6141
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Isoamyl acetate is a natural flavour ester, widely used as a source of banana flavour by the food industry. Williopsis saturnus var. saturnus is a yeast which can produce isoamyl acetate by esterification of amyl alcohols with acetyl coenzyme A via fermentation. The evaluation of this kind of production as an alternative way to obtain natural banana flavour could be possible, if the levels produced were high enough to make a commercial product. In this study, the effects of temperature (15°C and 25°C) and aeration (aerobic, semiaerobic, and anaerobic) on the production of isoamyl acetate by Williopsis saturnus var. saturnus from sugar beet molasses were examined. According to the results obtained, isoamyl acetate production rate and specific productivity were higher at 25°C than at 15°C and at semiaerobic condition than aerobic and anaerobic conditions. Williopsis saturnus var. saturnus showed a production rate of 0.703 mg (-1) h(-1) and a specific productivity of 0.0297 mg L(-1) cell(-1) h(-1) isoamyl acetate with semiaerobic condition at 25°C. The maximum amount of isoamyl acetate reached with these conditions was 118 mg/L.
[Mh] Termos MeSH primário: Fermentação/fisiologia
Pentanóis/metabolismo
Temperatura Ambiente
Williopsis/metabolismo
[Mh] Termos MeSH secundário: Aerobiose
Anaerobiose
Viabilidade Microbiana
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Pentanols); Z135787824 (isoamyl acetate)
[Em] Mês de entrada:1402
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130718
[St] Status:MEDLINE
[do] DOI:10.1155/2013/870802


  3 / 22 MEDLINE  
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[PMID]:23530838
[Au] Autor:Smitherman C; Gadda G
[Ad] Endereço:Department of Chemistry, Georgia State University, Atlanta, Georgia 30302-4098, USA.
[Ti] Título:Evidence for a transient peroxynitro acid in the reaction catalyzed by nitronate monooxygenase with propionate 3-nitronate.
[So] Source:Biochemistry;52(15):2694-704, 2013 Apr 16.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nitronate monooxygenase is a flavin-dependent enzyme that catalyzes the denitrification of propionate 3-nitronate (P3N) and other alkyl nitronates. The enzyme was previously known as 2-nitropropane dioxygenase, until its reclassification in 2010 by the IUBMB. Physiologically, the monooxygenase from fungi protects the organism from the environmental occurrence of P3N, which shuts down the Krebs cycle by inactivating succinate dehydrogenase and fumarase. The inhibition of these enzymes yields severe neurological disorders or death. Here, we have used for the first time steady-state and rapid kinetics, viscosity and pH effects, and time-resolved absorbance spectroscopy of the enzyme in turnover with P3N and the substrate analogue ethyl nitronate (EN) to elucidate the mechanism of the reaction. A transient increase in absorbance at ∼300 nm, never reported before, was seen during steady-state turnover of the enzyme with P3N and oxygen, with no concomitant changes between 400 and 600 nm. The transient species was not detected when oxygen was absent. Anaerobic reduction of the enzyme with P3N yielded anionic flavosemiquinone and was fast (e.g., ≥1900 s(-1)). Steady-state kinetics demonstrated that oxygen reacts before the release of the product of P3N oxidation from the enzyme. No pH effects were seen with P3N on kcat/Km, kcat/Koxygen, and kcat; in contrast, with EN, the kcat/Km and kcat decreased with increasing pH defining two plateaus and a pKa ∼ 8.0. Solvent viscosity at the pH optima suggested product release as being partially controlling the overall rate of turnover with the physiological substrate and its analogue. A mechanism that satisfies the kinetic results is proposed.
[Mh] Termos MeSH primário: Dioxigenases/química
Dioxigenases/metabolismo
Nitrocompostos/química
Propionatos/química
Williopsis/enzimologia
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Cinética
Nitrocompostos/metabolismo
Propionatos/metabolismo
Solventes
Análise Espectral/métodos
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Nitro Compounds); 0 (Propionates); 0 (Solvents); EC 1.13.11.- (Dioxygenases); EC 1.13.12.16 (2-nitropropane dioxygenase); QY4L0FOX0D (3-nitropropionic acid)
[Em] Mês de entrada:1307
[Cu] Atualização por classe:151119
[Lr] Data última revisão:
151119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130328
[St] Status:MEDLINE
[do] DOI:10.1021/bi400030d


  4 / 22 MEDLINE  
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[PMID]:23171032
[Au] Autor:Lee PR; Kho SH; Yu B; Curran P; Liu SQ
[Ad] Endereço:Food Science and Technology Programme, Department of Chemistry, National University of Singapore, Science Drive 3, Singapore.
[Ti] Título:Yeast ratio is a critical factor for sequential fermentation of papaya wine by Williopsis saturnus and Saccharomyces cerevisiae.
[So] Source:Microb Biotechnol;6(4):385-93, 2013 Jul.
[Is] ISSN:1751-7915
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The growth kinetics and fermentation performance of Williopsis saturnus and Saccharomyces cerevisiae at ratios of 10:1, 1:1 and 1:10 (W.:S.) were studied in papaya juice with initial 7-day fermentation by W.saturnus, followed by S. cerevisiae. The growth kinetics of W. saturnus were similar at all ratios, but its maximum cell count decreased as the proportion of S. cerevisiae was increased. Conversely, there was an early death of S. cerevisiae at the ratio of 10:1. Williopsis saturnus was the dominant yeast at 10:1 ratio that produced papaya wine with elevated concentrations of acetate esters. On the other hand, 1:1 and 1:10 ratios allowed the coexistence of both yeasts which enabled the flavour-enhancing potential of W.saturnus as well as the ethyl ester and alcohol-producing abilities of S. cerevisiae. In particular, 1:1 and 1:10 ratios resulted in production of more ethyl esters, alcohols and 2-phenylethyl acetate. However, the persistence of both yeasts at 1:1 and 1:10 ratios led to formation of high levels of acetic acid. The findings suggest that yeast ratio is a critical factor for sequential fermentation of papaya wine by W.saturnus and S. cerevisiae as a strategy to modulate papaya wine flavour.
[Mh] Termos MeSH primário: Carica/metabolismo
Saccharomyces cerevisiae/metabolismo
Williopsis/metabolismo
Vinho/microbiologia
[Mh] Termos MeSH secundário: Acetatos/metabolismo
Ácido Acético/metabolismo
Etanol/metabolismo
Fermentação
Aromatizantes/metabolismo
Álcool Feniletílico/análogos & derivados
Álcool Feniletílico/metabolismo
Saccharomyces cerevisiae/crescimento & desenvolvimento
Williopsis/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetates); 0 (Flavoring Agents); 3K9958V90M (Ethanol); 67733846OW (2-phenylethyl acetate); ML9LGA7468 (Phenylethyl Alcohol); Q40Q9N063P (Acetic Acid)
[Em] Mês de entrada:1312
[Cu] Atualização por classe:150222
[Lr] Data última revisão:
150222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:121123
[St] Status:MEDLINE
[do] DOI:10.1111/1751-7915.12008


  5 / 22 MEDLINE  
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[PMID]:22800660
[Au] Autor:Li X; Chan LJ; Yu B; Curran P; Liu SQ
[Ad] Endereço:Food Science and Technology Programme, Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
[Ti] Título:Fermentation of three varieties of mango juices with a mixture of Saccharomyces cerevisiae and Williopsis saturnus var. mrakii.
[So] Source:Int J Food Microbiol;158(1):28-35, 2012 Aug 01.
[Is] ISSN:1879-3460
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:This study was carried out to ascertain the behavior and fermentation performance of mixed yeasts in mango juices of three varieties. Saccharomyces cerevisiae MERIT.ferm and Williopsis saturnus var. mrakii NCYC500 at a ratio of 1:1000 were simultaneously inoculated into juices of three mango (Mangifera indica L.) varieties (R2E2, Harum Manis and Nam Doc Mai). Both yeasts grew well in all juices and there was no early growth arrest of either yeast, but there was late death of W. saturnus var. mrakii NCYC500 in the Nam Doc Mai juice. Fructose, glucose and sucrose were consumed to trace levels in all juices. Changes in citric, tartaric, malic, acetic and succinic acids varied with mango varieties. While the changes of major volatiles were similar in all varieties, there were significant varietal differences in the volatile composition of the resultant mango wines. The volatiles, especially most of the terpenes, of the juices decreased drastically and new volatiles such as ß-citronellol were formed. R2E2 wine had more fruity, sweet and creamy notes, and retained more of its original character due to a higher retention of ketones/lactones. Harum Manis wine had the lowest aroma intensity with more green and terpenic notes associated with higher levels of residual terpenes than the other two varieties. Nam Doc Mai wine possessed the highest aroma intensity with winey, yeasty, fruity and floral notes attributed to higher amounts of alcohols, acetate esters and ethyl esters. These findings may help develop different styles of mango wine.
[Mh] Termos MeSH primário: Fermentação
Mangifera
Saccharomyces cerevisiae/crescimento & desenvolvimento
Williopsis/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Acetatos
Álcoois
Bebidas
Ésteres
Saccharomycetales
Olfato
Paladar
Vinho
Leveduras/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetates); 0 (Alcohols); 0 (Esters)
[Em] Mês de entrada:1212
[Cu] Atualização por classe:120731
[Lr] Data última revisão:
120731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120718
[St] Status:MEDLINE
[do] DOI:10.1016/j.ijfoodmicro.2012.06.015


  6 / 22 MEDLINE  
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[PMID]:22464989
[Au] Autor:Francis K; Nishino SF; Spain JC; Gadda G
[Ad] Endereço:Department of Chemistry, Georgia State University, Atlanta, GA 30302-409, USA.
[Ti] Título:A novel activity for fungal nitronate monooxygenase: detoxification of the metabolic inhibitor propionate-3-nitronate.
[So] Source:Arch Biochem Biophys;521(1-2):84-9, 2012 May.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nitronate monooxygenase (NMO; E.C. 1.13.12.16) oxidizes alkyl nitronates to aldehydes and nitrite. Although the biochemistry of the enzyme from fungal sources has been studied extensively, the physiological role is unknown. The ability of NMO to detoxify propionate-3-nitronate was tested by measuring growth of recombinant Escherichia coli containing the gene encoding for the enzyme in either the absence or presence of the nitronate and its conjugate acid 3-nitropropionate. The mixture propionate-3-nitronate/3-nitropropionate is toxic to E. coli cells lacking expression of NMO, but the toxicity is overcome through either induction of the gene for NMO or through addition of exogenous enzyme to the cultures. Both Williopsis saturnus and Neurospora crassa were able to grow in the presence of 0.4mM propionate-3-nitronate and 19.6mM 3-nitropropionate, while a knockout mutant of N. crassa lacking NMO was inhibited by concentrations of propionate-3-nitronate and 3-nitropropionate >0.3 and 600µM, respectively. These results strongly support the conclusion that NMO functions to protect the fungi from the environmental occurrence of the metabolic toxin.
[Mh] Termos MeSH primário: Antimetabólitos/metabolismo
Proteínas Fúngicas/metabolismo
Nitrocompostos/metabolismo
Oxirredutases/metabolismo
Propionatos/metabolismo
[Mh] Termos MeSH secundário: Antimetabólitos/toxicidade
Escherichia coli/efeitos dos fármacos
Escherichia coli/metabolismo
Proteínas Fúngicas/genética
Técnicas de Inativação de Genes
Genes Fúngicos
Cinética
Desentoxicação Metabólica Fase I
Neurospora crassa/efeitos dos fármacos
Neurospora crassa/enzimologia
Neurospora crassa/genética
Neurospora crassa/crescimento & desenvolvimento
Nitrocompostos/toxicidade
Oxirredutases/genética
Propionatos/toxicidade
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Especificidade por Substrato
Superóxidos/metabolismo
Williopsis/enzimologia
Williopsis/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Antimetabolites); 0 (Fungal Proteins); 0 (Nitro Compounds); 0 (Propionates); 0 (Recombinant Proteins); 11062-77-4 (Superoxides); EC 1.- (Oxidoreductases); EC 1.7.3.- (propionate-3-nitronate oxidase); QY4L0FOX0D (3-nitropropionic acid)
[Em] Mês de entrada:1206
[Cu] Atualização por classe:151119
[Lr] Data última revisão:
151119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120403
[St] Status:MEDLINE
[do] DOI:10.1016/j.abb.2012.03.015


  7 / 22 MEDLINE  
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[PMID]:22370952
[Au] Autor:Tan AW; Lee PR; Seow YX; Ong PK; Liu SQ
[Ad] Endereço:Food Science and Technology Programme, Department of Chemistry, National University of Singapore, Science Drive 3, Singapore.
[Ti] Título:Volatile sulphur compounds and pathways of L-methionine catabolism in Williopsis yeasts.
[So] Source:Appl Microbiol Biotechnol;95(4):1011-20, 2012 Aug.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Volatile sulphur compounds (VSCs) are important to the food industry due to their high potency and presence in many foods. This study assessed for the first time VSC production and pathways of L: -methionine catabolism in yeasts from the genus Williopsis with a view to understanding VSC formation and their potential flavour impact. Five strains of Williopsis saturnus (var. saturnus, var. subsufficiens, var. suavolens, var. sargentensis and var. mrakii) were screened for VSC production in a synthetic medium supplemented with L: -methionine. A diverse range of VSCs were produced including dimethyl disulphide, dimethyl trisulphide, 3-(methylthio)-1-propanal (methional), 3-(methylthio)-1-propanol (methionol), 3-(methylthio)-1-propene, 3-(methylthio)-1-propyl acetate, 3-(methylthio)-1-propanoic acid (methionic acid) and ethyl 3-(methylthio)-1-propanoate, though the production of these VSCs varied between yeast strains. W. saturnus var. saturnus NCYC22 was selected for further studies due to its relatively high VSC production. VSC production was characterised step-wise with yeast strain NCYC22 in coconut cream at different L: -methionine concentrations (0.00-0.20%) and under various inorganic sulphate (0.00-0.20%) and nitrogen (ammonia) supplementation (0.00-0.20%), respectively. Optimal VSC production was obtained with 0.1% of L: -methionine, while supplementation of sulphate had no significant effect. Nitrogen supplementation showed a dramatic inhibitory effect on VSC production. Based on the production of VSCs, the study suggests that the Ehrlich pathway of L: -methionine catabolism is operative in W. saturnus yeasts and can be manipulated by adjusting certain nutrient parameters to control VSC production.
[Mh] Termos MeSH primário: Metionina/metabolismo
Compostos de Enxofre/metabolismo
Williopsis/metabolismo
[Mh] Termos MeSH secundário: Meios de Cultura
Fermentação
Volatilização
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Culture Media); 0 (Sulfur Compounds); AE28F7PNPL (Methionine)
[Em] Mês de entrada:1211
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120229
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-012-3963-x


  8 / 22 MEDLINE  
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[PMID]:22209575
[Au] Autor:Wang XX; Chi Z; Peng Y; Wang XH; Ru SG; Chi ZM
[Ad] Endereço:UNESCO Chinese Center of Marine Biotechnology and Institute of Marine Biodiversity and Evolution, Ocean University of China, Yushan Road, No. 5, Qingdao, China.
[Ti] Título:Purification, characterization and gene cloning of the killer toxin produced by the marine-derived yeast Williopsis saturnus WC91-2.
[So] Source:Microbiol Res;167(9):558-63, 2012 Oct 12.
[Is] ISSN:1618-0623
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:As the killer toxin produced by Williopsis saturnus WC91-2 could kill many sensitive yeast strains, including the pathogenic ones, the extracellular killer toxin in the supernatant of cell culture of the marine yeast strain was purified and characterized. The molecular mass of the purified killer toxin was estimated to be 11.0 kDa according to the data from SDS-PAGE. The purified killer toxin had killing activity, but could not hydrolyze laminarin. The optimal conditions for action of the purified killer toxin against the pathogenic yeast Metschnikowia bicuspidate WCY were the assay medium with 10% NaCl, pH 3-3.5 and temperature 16 °C. The gene encoding the killer toxin from the marine killer yeast WC91-2 was cloned and the ORF of the gene was 378 bp. The deduced protein from the cloned gene encoding the killer toxin had 125 amino acids with calculated molecular weight of 11.6 kDa. It was also found that the N-terminal amino acid sequence of the purified killer toxin had the same corresponding sequence deduced from the cloned killer toxin gene in this marine yeast, confirming that the purified killer toxin was indeed encoded by the cloned gene.
[Mh] Termos MeSH primário: Clonagem Molecular
Fatores Matadores de Levedura/genética
Fatores Matadores de Levedura/isolamento & purificação
Água do Mar/microbiologia
Williopsis/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Fatores Matadores de Levedura/química
Fatores Matadores de Levedura/farmacologia
Dados de Sequência Molecular
Peso Molecular
Filogenia
Alinhamento de Sequência
Williopsis/classificação
Williopsis/genética
Williopsis/isolamento & purificação
Leveduras/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Killer Factors, Yeast)
[Em] Mês de entrada:1302
[Cu] Atualização por classe:121012
[Lr] Data última revisão:
121012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120103
[St] Status:MEDLINE


  9 / 22 MEDLINE  
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[PMID]:21984025
[Au] Autor:Xu JL; Zhang X; Sun HY; Chi ZM
[Ad] Endereço:UNESCO Chinese Center of Marine Biotechnology, Ocean University of China, Yushan Road, No. 5, Qingdao, China.
[Ti] Título:Disruption of the gene encoding ß-1, 3-glucanase in marine-derived Williopsis saturnus WC91-2 enhances its killer toxin activity.
[So] Source:Mar Biotechnol (NY);14(3):261-9, 2012 Jun.
[Is] ISSN:1436-2236
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:As the ß-1, 3-glucanase produced by the marine-derived Williopsis saturnus WC91-2 could inhibit the activity of the killer toxin produced by the same yeast, the WsEXG1 gene encoding exo-ß-1, 3-glucanase in W. saturnus WC91-2 was disrupted. The disruptant WC91-2-2 only produced a trace amount of ß-1, 3-glucanase but had much higher activity of killer toxin than W. saturnus WC91-2. After the disruption of the WsEXG1 gene, the expression of the gene was significantly decreased from 100% in the cells of W. saturnus WC91-2 to 27% in the cells of the disruptant WC91-2-2 while the expression of the killer toxin gene in W. saturnus WC91-2 and the disruptant WC91-2-2 was almost the same. During 2-l fermentation, the disruptant WC91-2-2 could produce the highest amount of killer toxin (the size of the inhibition zone was 22 ± 0.7 mm) within 36 h when the cell growth reached the middle of the log phase.
[Mh] Termos MeSH primário: Inativação Gênica/fisiologia
Glucana 1,3-beta-Glucosidase/metabolismo
Fatores Matadores de Levedura/isolamento & purificação
Fatores Matadores de Levedura/metabolismo
Microbiologia da Água
Williopsis/metabolismo
[Mh] Termos MeSH secundário: Glucana 1,3-beta-Glucosidase/genética
Fatores Matadores de Levedura/genética
Oceanos e Mares
Williopsis/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Killer Factors, Yeast); EC 3.2.1.58 (Glucan 1,3-beta-Glucosidase)
[Em] Mês de entrada:1208
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:111011
[St] Status:MEDLINE
[do] DOI:10.1007/s10126-011-9409-0


  10 / 22 MEDLINE  
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[PMID]:20967498
[Au] Autor:Ochigava I; Collier PJ; Walker GM; Hakenbeck R
[Ad] Endereço:Department of Microbiology, University of Kaiserslautern, Paul-Ehrlich St 23, 67663 Kaiserslautern, Germany.
[Ti] Título:Williopsis saturnus yeast killer toxin does not kill Streptococcus pneumoniae.
[So] Source:Antonie Van Leeuwenhoek;99(3):559-66, 2011 Mar.
[Is] ISSN:1572-9699
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Streptococcus pneumoniae is an important human bacterial pathogen, and the increase in antibiotic resistance demands the development of new antimicrobial compounds. Several reports have suggested that yeast killer toxins show activity against bacteria and we therefore investigated the activity of K9 killer toxin from the yeast Williopsis saturnus var. mrakii NCYC 500 against S. pneumoniae. However, no inhibition of bacterial growth was observed with concentrated K9 preparations in agar diffusion assays and in liquid culture. Although cell morphology was slightly affected by K9 treatment, no effect on cellular viability was detectable, and K9 had no stimulatory effect on cell lysis induced by ß-lactams or Triton X-100. This indicated that K9 did not contribute to cell wall damage. Moreover, flow cytometry was used as a sensitive assessment of integrity of cells exposed to killer toxin. No significant damage of S. pneumoniae cells was evident, although minor changes in fluorescence suggested that K9 killer toxin may interact with bacterial surface components.
[Mh] Termos MeSH primário: Anti-Infecciosos/farmacologia
Fatores Matadores de Levedura/farmacologia
Streptococcus pneumoniae/efeitos dos fármacos
Williopsis/metabolismo
[Mh] Termos MeSH secundário: Anti-Infecciosos/metabolismo
Citometria de Fluxo
Fatores Matadores de Levedura/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Killer Factors, Yeast)
[Em] Mês de entrada:1106
[Cu] Atualização por classe:110217
[Lr] Data última revisão:
110217
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:101023
[St] Status:MEDLINE
[do] DOI:10.1007/s10482-010-9524-3



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