Guidi-Rontani C, Danchin A, Ullmann A
J Bacteriol. 1981 Dec;148(3):753-61. doi: 10.1128/jb.148.3.753-761.1981.
A mutant, cyaR1, affecting regulation of adenylate cyclase expression or activity is described. It was obtained as a thermoresistant revertant of a strain harboring a thermosensitive transcription termination factor, rho (rho-15). This mutant failed to synthesize adenosine 3',5'-phosphate and exhibited a carbohydrate-negative phenotype. A secondary mutation at the crp locus (crpC) restored the ability of the mutant to synthesize adenosine 3',5'-phosphate, enabled the expression of catabolite-sensitive operons, and conferred on the strain an extreme sensitivity to catabolite repression. In addition, we showed that the crpC mutation restored the pleiotropic carbohydrate-positive phenotype even in a delta cya background. We interpret this to mean that the adenosine 3',5'-phosphate receptor protein regulates negatively either the activity or synthesis of adenylate cyclase and that the cyaR1 mutation is either in a regulatory protein or a regulatory site of adenylate cyclase.
描述了一种影响腺苷酸环化酶表达或活性调控的突变体cyaR1。它是作为携带温度敏感型转录终止因子rho（rho-15）的菌株的耐热回复突变体获得的。该突变体无法合成3',5'-磷酸腺苷，并表现出碳水化合物阴性表型。crp位点的二次突变（crpC）恢复了突变体合成3',5'-磷酸腺苷的能力，使分解代谢敏感型操纵子得以表达，并赋予该菌株对分解代谢阻遏的极端敏感性。此外，我们表明，即使在δcya背景下，crpC突变也恢复了多效性碳水化合物阳性表型。我们将此解释为3',5'-磷酸腺苷受体蛋白对腺苷酸环化酶的活性或合成起负调控作用，并且cyaR1突变位于调节蛋白或腺苷酸环化酶的调节位点中。
