Activation of neutral trehalase by fermentable sugars and cAMP in the fission yeastSchizosaccharomyces pombe

Derepressed cells of Schizosaccharomyces pombe 972 h− suspended in the presence of glucose or other fermentable sugars displayed a transient activation of trehalase which was not blocked by cycloheximide. Repressed cells were unable to show glucose-induced trehalase stimulation. Nitrogen sources, protonophores or uncouplers failed to produce direct trehalase activation but increased the activity of the enzyme in the presence of glucose. Exogenous cAMP induced a rapid and pronounced stimulation of trehalase in both repressed and derepressed cells suggesting that the response to glucose includes activation of adenylate cyclase as part of a cAMP signalling pathway that increases the catalytic activity of trehalase by enzyme modification.