Effect of glucose and its analogues on the accumulation and release of cyclic adenosine 3',5'-monophosphate in a membrane fraction of Escherichia coli: relation to beta-galactosidase synthesis.
AUTOR(ES)
Seto, H
RESUMO
Correlation between beta-galactosidase synthesis and cyclic adenosine 3',5'-monophosphate (cAMP) levels in a membrane fraction obtained from disrupted spheroplasts of Escherichia coli was investigated. Repression of beta-galactosidase synthesis in the membrane fraction by glucose-6-phosphate and by 2-deoxyglucose differed in sensitivity to reversal by cAMP. The difference between the two repressions could be due to the fact that glucose-6-phosphate inhibited severely the accumulation of exogenous [3-H]cAMP by the membrane fraction, whereas 2-deoxyglucose had little effect on the accumulation of the nucleotide. On the other hand, a quick decrease in the level of [3-H]cAMP preaccumulated in the membrane fraction resulted from addition of either glucose-6-phosphate or 2-deoxyglucose. Results reported here suggest that repression of beta-galactosidase synthesis is associated with anabrupt decrease in cAMP levels at the intramembranal sites where beta-galactosidase is synthesized, and the major, if not sole, mechanism which leads to instantaneous drop of cAMP level is via the release of cAMP, but not by degradation of the nucleotide since the membrane fraction retained less than 10 percent of cellular cyclic phosphodiesterase and the activity of the enzyme was not affected by repressing sugars.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=246105Documentos Relacionados
- Effects of 8-substituted analogs of cyclic adenosine 3',5'-monophosphate on in vivo and in vitro syntheses of beta-galactosidase in Escherichia coli.
- The role of the lac promotor locus in the regulation of beta-galactosidase synthesis by cyclic 3',5'-adenosine monophosphate.
- Cyclic Adenosine 3′,5′-Monophosphate in Escherichia coli
- Cyclic adenosine 3',5'-monophosphate regulation of membrane energetics in Escherichia coli.
- Antipain lethality to Escherichia coli: dependence upon cyclic adenosine 3',5'-monophosphate and its receptor protein.