Research Center for Resistant Cells, Chosun University Medical School, 375 Seosuk-Dong, Dong-Gu, Gwangju 501-759, Republic of Korea.
Microb Pathog. 2010 Dec;49(6):348-53. doi: 10.1016/j.micpath.2010.07.003. Epub 2010 Jul 16.
In Vibrio vulnificus, cAMP-receptor protein (CRP) and the quorum-sensing regulator SmcR are simultaneously and cooperatively required for the metalloprotease vvpE gene expression, rather than sequentially in a regulatory cascade. However, this study shows a new temporal and functional sequence between the two factors in regulating vvpE expression. A crp mutation inhibited vvpE expression with growth impairment from early stage. In contrast, a smcR mutation inhibited vvpE expression only at the late stage with no effect on growth. A crp-smcR double mutation severely inhibited vvpE expression with growth impairment from early stage. The inhibited vvpE expression was restored only at the early stage by a crp single complementation, but not at all by a smcR complementation. These results indicate that CRP functions as an essential activator, whereas SmcR functions in the presence of CRP for full vvpE expression.
在创伤弧菌中，cAMP 受体蛋白 (CRP) 和群体感应调节因子 SmcR 同时且协同地被需要用于金属蛋白酶 vvpE 基因的表达，而不是在调控级联中依次进行。然而，这项研究在调节 vvpE 表达方面显示了这两个因素之间的新的时间和功能顺序。CRP 突变抑制 vvpE 表达，同时伴随着早期生长受损。相比之下，SmcR 突变仅在晚期抑制 vvpE 表达，对生长没有影响。CRP-SmcR 双突变严重抑制 vvpE 表达，同时伴随着早期生长受损。受抑制的 vvpE 表达仅在早期通过 CRP 单一互补得到恢复，但 SmcR 互补则完全无效。这些结果表明，CRP 作为必需的激活因子起作用，而 SmcR 在 CRP 存在的情况下起作用以实现 vvpE 的完全表达。
