ISSN:
0749-503X
Keywords:
Crabtree effect
;
sugar transport
;
growth kinetics
;
yeast
;
chemostat
;
Life and Medical Sciences
;
Genetics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
The glucose transport capacity of Saccharomyces cerevisiae CBS 8066 was studied in aerobic glucose-limited chemostat cultures. Two different transport systems were encountered with affinity constants of 1 and 20 mM, respectively. The capacity of these carriers (Vmax) was dependent on the dilution rate and the residual glucose concentration in the culture. From the residual glucose concentration in the fermenter and the kinetic constants of glucose transport, their in situ contribution to glucose consumption was determined. The sum of these calculated in situ transport rates correlated well with the observed rate of glucose consumption of the culture.The growth kinetics of S. cerevisiae CBS 8066 in glucose-limited cultures were rather perculiar. At low dilution rates, at which glucose was completely respired, the glucose concentration in the fermenter was constant at 110 μM, independent of the glucose concentration in the reservoir. At high dilution rates, characterized by the occurrence of both respiration and alcoholic fermentation, the residual substrate concentration followed Monod kinetics. In this case, however, the overall affinity constant was dependent on the reservoir glucose concentration.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/yea.320050305
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