When a wild-type strain of Escherichia coli contains lactose permease, the accumulation of cyclic AMP (cAMP) by intact cells is inhibited by lactose. This inhibitory effect of lactose is observed in a strain with a mutant cAMP phosphodiesterase and therefore involves a regulation of adenylate cyctase activity. Some E. coli strains carrying mutations in lactose permease show an effect opposite to that of the wild-type strain; the accumulation of cAMP by intact cells is stimulated by lactose, but only when the mutant permease is present. Insertion of lactose permease into the membrane of ceils can produce a change in the specific activity of adenylate cycIase; induction of the wild-type transporter is correlated with a decrease in the specific activity, while implantation of a mutant form of lactose permease can lead to an increase in the specific activity. From these data, it is suggested that the state of the lactose transporter in the cell membrane influences the activity of adenytate cyclase.
Research Article| January 01 1981
Stimulation of Escherichia coli adenylate cyclase by lactose in strains carrying mutations in lactose permease
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Alan Peterkofsky, Celia Gazdar; Stimulation of Escherichia coli adenylate cyclase by lactose in strains carrying mutations in lactose permease. Biosci Rep 1 January 1981; 1 (1): 53–60. doi: https://doi.org/10.1007/BF01115149
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