den Blaauwen J L, Postma P W
J Bacteriol. 1985 Oct;164(1):477-8. doi: 10.1128/jb.164.1.477-478.1985.
We investigated the claim (J. Daniel, J. Bacteriol. 157:940-941, 1984) that nonphosphorylated enzyme IIIGlc of the phosphoenolpyruvate:sugar phosphotransferase system is required for full synthesis of bacterial cyclic AMP (cAMP). In crp strains of Salmonella typhimurium, cAMP synthesis by intact cells was regulated by the phosphorylation state of enzyme IIIGlc. Introduction of either a pstHI deletion mutation or a crr::Tn10 mutation resulted in a low level of cAMP synthesis. In contrast, crp strains containing a leaky pstI mutation exhibited a high level of cAMP synthesis which was inhibited by phosphotransferase system carbohydrates. From these results, we conclude that phosphorylated enzyme IIIGlc rather than nonphosphorylated enzyme IIIGlc is required for full cAMP synthesis.
我们对下述观点进行了研究（J. 丹尼尔，《细菌学杂志》157:940 - 941，1984年），即磷酸烯醇丙酮酸:糖磷酸转移酶系统的非磷酸化的酶IIIGlc是细菌环磷酸腺苷（cAMP）完全合成所必需的。在鼠伤寒沙门氏菌的crp菌株中，完整细胞合成cAMP受酶IIIGlc磷酸化状态的调控。引入pstHI缺失突变或crr::Tn10突变都会导致cAMP合成水平较低。相反，含有渗漏型pstI突变的crp菌株表现出高水平的cAMP合成，而这种合成会受到磷酸转移酶系统糖类的抑制。从这些结果我们得出结论，完全合成cAMP所需的是磷酸化的酶IIIGlc而非非磷酸化的酶IIIGlc。
