Baron Szilvia, Eisenbach Michael
Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel.
FEBS Lett. 2017 Jul;591(13):1958-1965. doi: 10.1002/1873-3468.12699. Epub 2017 Jun 11.
Recent studies demonstrated the dependence of speed adaptation in Escherichia coli on acetylation of the chemotaxis signaling molecule CheY. Here, we examined whether CheY acetylation is involved in chemotactic adaptation. A mutant lacking the acetylating enzyme acetyl-CoA synthetase (Acs) requires more time to adapt to attractant stimulation, and vice versa to repellent stimulation. This effect is avoided by conditions that favor production of acetyl-CoA, thus enabling Acs-independent CheY autoacetylation, or reversed by expressing Acs from a plasmid. These findings suggest that CheY should be acetylated for ordinary adaptation time, and that the function of this acetylation in adaptation is to enable the motor to shift its rotation to clockwise. We further identify the enzyme phosphotransacetylase as a third deacetylase of CheY in E. coli.
最近的研究表明，大肠杆菌中速度适应依赖于趋化信号分子CheY的乙酰化。在此，我们研究了CheY乙酰化是否参与趋化适应。缺乏乙酰化酶乙酰辅酶A合成酶（Acs）的突变体需要更多时间来适应吸引物刺激，反之，对驱避剂刺激的适应时间则更短。有利于乙酰辅酶A产生的条件可避免这种效应，从而实现不依赖Acs的CheY自动乙酰化，或者通过从质粒表达Acs来逆转这种效应。这些发现表明，CheY需要被乙酰化才能有正常的适应时间，并且这种乙酰化在适应过程中的作用是使马达将其旋转方向转变为顺时针。我们进一步确定磷酸转乙酰酶是大肠杆菌中CheY的第三种脱乙酰酶。
