Dills S E, Dobrogosz W J
J Bacteriol. 1977 Sep;131(3):854-65. doi: 10.1128/jb.131.3.854-865.1977.
Mutants of Escherichia coli K-12 lacking functional adenylate cyclase (cya) or the cyclic adenosine 3',5'-monophosphate (cAMP) receptor protein (crp) were compared with their wild type to evaluate the role played by the cAMP-cAMP receptor protein complex in regulating this organism's membrane-associated bioenergetic functions. Both mutants were found to be equally defective in carrying out various electron transport activities. In particular, their capacity for synthesizing a functional oxygen-linked transhydrogenase system was totally repressed, and their content of flavin adenine dinucleotide was reduced by approximately 85%. In addition, it was found that the mutant strains had a decreased ability to generate a protonmotive force and to use this chemiosmotic force to generate adenosine 5'-triphosphate. All these membrane-associated dysfunctions were completely restored to the wild-type state when the cya cells were grown in the presence of exogenous cAMP. As would be expected if these controls were operating at the transcriptional level, the crp cells retained the mutant character even when grown in the presence of this cyclic nucleotide.
将缺乏功能性腺苷酸环化酶（cya）或环腺苷酸（cAMP）受体蛋白（crp）的大肠杆菌K-12突变体与其野生型进行比较，以评估cAMP - cAMP受体蛋白复合物在调节该生物体膜相关生物能量功能中所起的作用。发现这两种突变体在进行各种电子传递活动时同样存在缺陷。特别是，它们合成功能性氧连接转氢酶系统的能力完全受到抑制，其黄素腺嘌呤二核苷酸含量降低了约85%。此外，还发现突变菌株产生质子动力的能力以及利用这种化学渗透力产生三磷酸腺苷的能力均下降。当cya细胞在外源cAMP存在下生长时，所有这些与膜相关的功能障碍都完全恢复到野生型状态。正如预期的那样，如果这些调控作用于转录水平，那么即使在这种环核苷酸存在的情况下生长，crp细胞仍保留突变特征。
