Yeasts characteristics

J. A. Barnett, R. W. Payne, and D. Yarrow, Yeasts Characteristics and Identification Cambridge University Press, Cambridge, 1983. 

Barnett JA, Payne RW and Yarrow D. 2000. Yeasts Characteristics and Identifications, 3rd ed. Cambridge, UK Cambridge University Press, pp. 395—401. 

Adams. A., D.E. Gotlschling. C. Kaiset, and T. Steams Methods in Yeast Gene tics, 1997. Cold Spring Harbor Laboratory Piess, Cold Spring Harbor. NY, 1999. Barnett, JA., D. Yarrow, and R.W. Payne. Yeasts Characteristics and Identification, Cambridge University Press, New York, NY, 2000. 

Barnett, J.A., Payne, R.W. and Yarrow, D. (eds) (1990) Yeasts Characteristics and Identification, 2nd edn, Cambridge University Press, Cambridge. 

Antonsson, B., Montessuit, S., Friedli, L., Payton, M.A., and Paravicini, G., 1994, Protein kinase C in yeast. Characteristics of the Saccharomyces cerevisiae PKC1 gene product. J Biol. Chem. 269 16821-16828. 

Barnett, J. A., Payne, R. W., Yarrow, D. (1983). Yeasts characteristics and identification. Cambridge, GBR Cambridge University Press. 

Biochemistry resulted from the early elucidation of the pathway of enzymatic conversion of glucose to ethanol by yeasts and its relation to carbohydrate metaboHsm in animals. The word enzyme means "in yeast," and the earfler word ferment has an obvious connection. Partly because of the importance of wine and related products and partly because yeasts are relatively easily studied, yeasts and fermentation were important in early scientific development and stiU figure widely in studies of biochemical mechanisms, genetic control, cell characteristics, etc. Fermentation yeast was the first eukaryote to have its genome elucidated. 

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). 

The quality of flour used ia the production of yeast-raised products depends on several factors, including the quality and characteristics of the wheat variety, the environmental conditions under which the wheat was grown, the skill of the miller in separating the endosperm of the wheat kernel from the germ and bran, and the proper treatment of the flour in the mill. 

FIGURE 12.37 Tertiary interactions in yeast phenylalanine tRNA. The molecnle is presented in the conventional cloverleaf secondary strnctnre generated by intrastrand hydrogen bonding. Solid lines connect bases that are hydrogen-bonded when this cloverleaf pattern is folded into the characteristic tRNA tertiary strnctnre (see also Figure 12.36). 

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