Is anyone out there an expert on yeast metabolism or know where I can find
out detailed information on it? We do a yeast fermentation experiment
where students compare fermentation rates by yeast of a variety of
carbohydrates: glucose, fructose, sucrose, galactose, maltose, raffinose,
Glucose, fructose and sucrose are all fermented at about the same rate.
Galactose and maltose are fermented slower than glucose and exhibit a lag
as if they are inducible. Amylose is not fermented and raffinose is
fermented at a rate about 1/3 that of glucose (sometimes a little greater
The question I have is about what specific mechanism accounts for the
induction or failure to be fermented. Is the inducible or lacking protein
(a) involved in cleavage of polymers, (b) involved in transport of monomers
or polymers, or (c) involved in facilitating entry of the resulting
monomers into the TCA cycle, or something else I'm not even thinking of?
Also, in the case of inducible metabolic enzymes, about how long does
induction generally take when the yeast are NOT grown on the sugar in
question? How does this compare with the "lifespan" of a single yeast cell
(i.e. before it becomes two new cells)?
Any answers or direction of where to find them would be greatly
appreciated. Please reply directly to me at rcberkel at uci.edu
Thanks! Our students are very interested in mechanism.
Rudi C. Berkelhamer
Department of Ecology & Evolutionary Biology
University of California, Irvine
Irvine, CA 92697-2525
phone: (949) 824-5573 *NOTE NEW AREA CODE*
FAX: (949) 824-2181 *NOTE NEW AREA CODE*
rcberkel at uci.eduhttp://www.bio.uci.edu/units/ee/faculty/berkelhamer.html