Inhibition by polyols of the heat-shock-induced activation of trehalase in the yeast Zygosaccharomyces rouxii.
Trehalase activity was markedly enhanced in Zygosaccharomyces rouxii upon exposure of the cells to a heat shock. The increase in trehalase was independent of rapid changes in the intracellular concentration of cAMP and was not blocked by inhibitors of protein synthesis. Trehalase activated in vivo by heat shock was deactivated in vitro by phosphatase, suggesting that heat stress triggers a cAMP-independent signalling pathway that includes the activation of trehalase by phosphorylation of the enzyme protein. The addition to these cells before heating of either glycerol or other polyols produced a significant decrease in the heat-shock induced activation of trehalase. However, the trehalose content in cells heat-shocked in the presence of polyols did not increase significantly, indicating that these compounds may also influence the synthesis of the disaccharide.
Fernandez
J
J
Department of Genetics and Microbiology, Facultad de Biologia, University of Murcia, Spain.
Soto
T
T
Vicente-Soler
J
J
Cansado
J
J
Gacto
M
M
D000469:Alkaline Phosphatase / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D005990:Glycerol / Q000494:pharmacology*; D018869:Heat-Shock Response; D010766:Phosphorylation; D011108:Polymers / Q000494:pharmacology; D013402:Sugar Alcohols / Q000494:pharmacology; D013696:Temperature; D014198:Trehalase / Q000378:metabolism*; D014199:Trehalose / Q000378:metabolism; D015003:Yeasts / Q000201:enzymology*
D011108:Polymers; D013402:Sugar Alcohols; C024617:polyol; D003513:Cycloheximide; D014199:Trehalose; D000242:Cyclic AMP; D000469:Alkaline Phosphatase; D014198:Trehalase; D005990:Glycerol