Laboratory yeast

Scientists have determined complete genomic sequences for a number of viruses, over fifteen bacteria, and laboratory yeast. Many pharmaceutical companies are interested in the sequence information from bacteria that cause disease, in the hopes that the information obtained will lead to new drug targets. 

Ibeas, J.I., Jimenez, J. (1996). Genomic complexity and chromosomal rearrangements in wine-laboratory yeast hybrids. Curr. Gen., 30, 410-416. 

In breweries using pure yeast cultures, the yeast may be isolated, selected and maintained at each brewery or by a central laboratory. Yeast may be transported in refrigerated containers in quantities sufficient to pitch a propagator or in small amounts for laboratory cultivation prior to propagation. Some companies rely on commercial laboratories to isolate and maintain their yeast. 

Genome sequencing of a eukaryote, a laboratory yeast strain of Saccharomyces cerevisiae... 

Antimalarial drug artemisinin has been produced from metabolically engineered laboratory yeast. The antimalarial comes from the Artemisia annua plant, which grows in Southeast Asia. Artemisinin could also possibly be used in cancer treatment. Scientists are able to synthesize large DNA molecules in the laboratory. Researchers have made artificial DNA containing all twenty-one genes encoding the small ribosomal subunit (cell protein factory) from Escherichia coli (E. colt). 

Bravim, R, PaUiano, F. L., Fernandes, A. A., Fernandes, P. M. Biotechnological properties of distillery and laboratory yeasts in response to industrial stresses. J Ind Microbiol Biotechnol. 2010b, 37,1071-1079. 

The elemental and vitamin compositions of some representative yeasts are Hsted in Table 1. The principal carbon and energy sources for yeasts are carbohydrates (usually sugars), alcohols, and organic acids, as weU as a few other specific hydrocarbons. Nitrogen is usually suppHed as ammonia, urea, amino acids or oligopeptides. The main essential mineral elements are phosphoms (suppHed as phosphoric acid), and potassium, with smaller amounts of magnesium and trace amounts of copper, zinc, and iron. These requirements are characteristic of all yeasts. The vitamin requirements, however, differ among species. Eor laboratory and many industrial cultures, a commercial yeast extract contains all the required nutrients (see also Mineral nutrients). 

G. I. De Becze, Classification of Yeasts, WaHerstein Laboratories Communications, 1958—1963. 

Grain that is usable as food or feed is an expensive substrate for this fermentation process. A cheaper substrate might be some source of cellulose such as wood or agricultural waste. This, however, requires hydrolysis of cellulose to yield glucose. Such a process was used in Germany during World War II to produce yeast as a protein substitute. Another process for the hydrolysis of wood, developed by the U.S. Forest Products Laboratory, Madison, Wisconsin, uses mineral acid as a catalyst. This hydrolysis industry is very large in the former Soviet Union but it is not commercial elsewhere. 

Mg or Ca in MeOH, " baker s yeast, Sm/l2, LiMe2NBH3, and tin complexes prepared from SnCl2 or Sn(SR)2. This reaction, combined with RX —+ RN3 (10-65), is an important way of converting alkyl halides RX to primary amines RNH2 in some cases the two procedures have been combined into one laboratory step. Sulfonyl azides (RSO2N3) have been reduced to sulfonamides (RSO2NH2) by irradiation in isopropyl alcohol and with NaH. ... 

Fraenkel D.G. (1982) Carbohydrate metabolism. In TheMolecular Biology of the Yeast Saccharomyces, vol. 2. Metabolism and Biosynthesis (eds J.N. Strathem, E.W. Jones J.R. Broach), pp. 1-37. Cold Spring Harbor, NY Cold Spring Harbor Laboratory. 

Sherman, F., Fink, G.R. and Hicks, J.B. (1985) Methods in Yeast Genetics, Cold Spring Harbor Laboratory, New York. 

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