Analytical differentiation of wine fermentations using pure and mixed yeast cultures

The superiority of methods involving the use of sporulation media containing acetate, first introduced by Stantial and Elder, over several commonly employed methods is established. A new method for obtaining ascospores from bakers' yeast cultures is recommended involving the direct transfer of vegetative cells from a solid nutrient medium to a solid medium containing acetate. High yields of ascospores are consistently produced after seven days' incubation. This method should lend itself particularly to use in the preparation of ascospores for instructional work, and for genetic research in yeast, and may also find application in yeast taxonomy. The technique recommended is as follows: vegetative yeast cells are multiplied on tomato juice agar or on dextrose nutrient agar, and are then transferred to a solid sporulation medium containing 0.04% dextrose, 0.14% anhydrous sodium acetate, and 2% agar.

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Synchronization of Budding Yeast Cultures

IFAC Proceedings Volumes ◽

10.3182/20110828-6-it-1002.01712 ◽

2011 ◽

Vol 44 (1) ◽

pp. 8384-8390

Author(s):

T.C. Neymann ◽

S. Wegerhoff ◽

S. Engell

Keyword(s):

Budding Yeast ◽

Yeast Cultures

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Effect of two commercial yeast cultures with Saccharomyces cerevisiae on ruminal fermentation and digestion in sheep fed sugar cane tops

Livestock Production Science ◽

10.1016/s0301-6226(99)00116-5 ◽

2000 ◽

Vol 63 (2) ◽

pp. 153-157 ◽

Cited By ~ 25

Author(s):

J.L. Arcos-Garcı́a ◽

F.A. Castrejón ◽

G.D. Mendoza ◽

E.P. Pérez-Gavilán

Keyword(s):

Saccharomyces Cerevisiae ◽

Sugar Cane ◽

Ruminal Fermentation ◽

Yeast Cultures ◽

Commercial Yeast

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Differentiation of Yeast Cultures in Ruminant Feedingstuffs Using a Rapid DNA Fingerprinting Technique

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600026489 ◽

1994 ◽

Vol 1994 ◽

pp. 101-101

Author(s):

Elizabeth Moore ◽

Denis R. Headon

Keyword(s):

Sodium Dodecyl ◽

Yeast Cells ◽

Microbial Populations ◽

Yeast Culture ◽

Yeast Cultures ◽

Yeast Strains ◽

Genetic Sequences ◽

Polymerase Chain ◽

Different Strains ◽

Triton X

Research indicates that certain yeast strains are beneficial in their capacity to stimulate key microbial populations. This stimulation is strain specific with similar yeast strains exerting their effect on totally different microbial populations. Future yeast culture supplements may contain mixtures of different strains designed to suit specific diets. This, therefore, requires the development of a rapid sensitive technique to differentiate among taxonomically similar yeast strains in animal diets. This technique, termed the Randomly Amplified Polymorphic DNA (RAPD) assay, is based upon the use of randomly designed short polynucleotide primers to amplify genetic sequences from the DNA of the desired yeast strain. Our objective involves the development of this technique to distinguish between closely related yeast strains present in feed. The feed sample investigated was a standard cattle ration containing three strains of Saccharomyces cerevisiae (1026, 2045 and 2020) and Candida utilis 3001 at a concentration of 106 CFU/g respectively. Isolation of single colonies of yeast strains present was achieved by feed extraction in dilution buffer followed by plating a series of dilutions on rose-bengal agar. Thirty randomly selected colonies were cultured in YPD (1% yeast extract, 2% peptone, 2% glucose) broth for 24 - 30 hours at 30°C. Genomic DNA was isolated from yeast cells by standard methods based on subjection of the cells to vortex mixing in the presence of glass beads, triton X-100, sodium dodecyl sulphate, phenol and chloroform. Isolated DNA from randomly selected colonies was amplified by Polymerase Chain Reaction (PCR) for 45 cycles of 1 min at 94°C, 1 min at 36°C and 1 min at 72°C using randomly designed 10 bp primers.

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The calculation of cellular parameters from the turbidity of yeast cultures may give rise to important errors

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.1985.tb00886.x ◽

1985 ◽

Vol 29 (3) ◽

pp. 335-337 ◽

Cited By ~ 8

Author(s):

Rosario Lagunas ◽

Eulalia Moreno

Keyword(s):

Yeast Cultures

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Saccharomyces cerevisiae (Baker’s Yeast) as an Interfering RNA Expression and Delivery System

Current Drug Targets ◽

10.2174/1389450120666181126123538 ◽

2019 ◽

Vol 20 (9) ◽

pp. 942-952 ◽

Cited By ~ 9

Author(s):

Molly Duman-Scheel

Keyword(s):

Saccharomyces Cerevisiae ◽

Rna Interference ◽

Genetic Model ◽

Model Organism ◽

Rna Expression ◽

Commercial Development ◽

Rna Integrity ◽

Yeast Cultures ◽

Ideal System ◽

Interfering Rna

The broad application of RNA interference for disease prevention is dependent upon the production of dsRNA in an economically feasible, scalable, and sustainable fashion, as well as the identification of safe and effective methods for RNA delivery. Current research has sparked interest in the use of Saccharomyces cerevisiae for these applications. This review examines the potential for commercial development of yeast interfering RNA expression and delivery systems. S. cerevisiae is a genetic model organism that lacks a functional RNA interference system, which may make it an ideal system for expression and accumulation of high levels of recombinant interfering RNA. Moreover, recent studies in a variety of eukaryotic species suggest that this microbe may be an excellent and safe system for interfering RNA delivery. Key areas for further research and development include optimization of interfering RNA expression in S. cerevisiae, industrial-sized scaling of recombinant yeast cultures in which interfering RNA molecules are expressed, the development of methods for largescale drying of yeast that preserve interfering RNA integrity, and identification of encapsulating agents that promote yeast stability in various environmental conditions. The genetic tractability of S. cerevisiae and a long history of using this microbe in both the food and pharmaceutical industry will facilitate further development of this promising new technology, which has many potential applications of medical importance.

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Glucose Signaling Pathway and Growth Conditions Regulate Gene Expression in Retrotransposon Ty2

Zeitschrift für Naturforschung C ◽

10.1515/znc-2009-7-811 ◽

2009 ◽

Vol 64 (7-8) ◽

pp. 526-532 ◽

Cited By ~ 3

Author(s):

Sezai Türkel ◽

Özgür Bayram ◽

Elif Arık

Keyword(s):

Gene Expression ◽

Growth Conditions ◽

Glucose Sensors ◽

Yeast Cells ◽

Growth Stages ◽

Regulate Gene Expression ◽

Glucose Signaling ◽

Yeast Cultures ◽

Membrane Bound ◽

High Level

Gene expression in the yeast retrotransposon Ty2 is regulated at transcriptional and translational levels. In this study, we have shown that the transcription of Ty2 is partially dependent on the membrane-bound glucose sensors Gpr1p and Mth1p in Saccharomyces cerevisiae. Transcription of Ty2 decreased approx. 3-fold in the gpr1, mth1 yeast mutant. Moreover, our results revealed that the transcription of Ty2 fluctuates during the growth stages of S. cerevisae. Both transcription and the frameshift rate of Ty2 rapidly dropped when the stationary stage yeast cells were inoculated into fresh medium. There was an instant activation of Ty2 transcription and a high level expression during the entire logarithmic stage of yeast growth. However, the transcription of Ty2 decreased 2-fold when the yeast cultures entered the stationary stage. The frameshift rate in Ty2 also varied depending on the growth conditions. The highest frameshift level was observed during the mid-logarithmic stage. It decreased up to 2-fold during the stationary stage. Furthermore, we have found that the frameshift rate of Ty2 diminished at least 5-fold in slowly growing yeasts. These results indicate that the transcription and the frameshift efficiency are coordinately regulated in the retrotransposon Ty2 depending on the growth conditions of S. cerevisiae.

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