

@mastersthesis {6445,
	title = {Construction and analysis of a starch-degrading strain of distillers{\textquoteright} yeast},
	year = {1994},
	note = {U059856},
	school = {Heriot-Watt University (United Kingdom)},
	type = {phdPh.{D}.},
	address = {Ann Arbor},
	abstract = {A primary target in whisky fermentations is to maximise spirit yield. Improvement in spirit yield might be achieved by the genetic modification of distillers{\textquoteright} yeast, so that residual carbohydrate in the wash (e.g. certain limit dextrins) can be fermented to alcohol. RY40 is a widely used commercial distilling strain of Saccharomyces cerevisiae. Glucoamylase, encoded by the STA gene, hydrolyses starch to glucose and is produced by a number of distilling strains. Unfortunately, the production of glucoamylase in such strains is severely limited by the presence of genetic controls. RY40 is thought to carry at least one copy of a STA gene, but it produces virtually no detectable glucoamylase. The STA2 gene from Saccharomyces diastaticus was subcloned into RY40, using the multicopy plasmid pLHD301-NEO. The transformant, designated RY51, produced approximately seven times more glucoamylase than RY40. Using a probe based in part of the sequence of the STA2 gene, Southern blot analysis revealed the presence of pLHD301-NEO in RY51 at approximately nine copies per cell, and also the presence of the STA gene in RY40. Comparison between RY40 and RY51 in standard gravity malt and grain wort laboratory scale fermentations revealed no significant differences in ethanol production. However, in high gravity malt wort fermentations RY51 produced significantly more ethanol than RY40. (DX180,228)},
	keywords = {(UMI)AAIU059856, 0539:Agricultural engineering, Agricultural engineering, Applied sciences, Bibliographies, Psychology{\textendash}Abstracting, Statistics},
	url = {http://search.proquest.com/docview/301500703?accountid=14270},
	author = {Daubenspeck, R L}
}
