Wolfe A J, Conley M P, Berg H C
Department of Cellular and Developmental Biology, Harvard University, Cambridge, MA 02138.
Proc Natl Acad Sci U S A. 1988 Sep;85(18):6711-5. doi: 10.1073/pnas.85.18.6711.
Cells of Escherichia coli deleted for genes that code for the transducers and all the known cytoplasmic Che proteins except CheY responded reversibly to the addition of acetate by spinning their flagellar motors clockwise. By varying growth conditions and using metabolic inhibitors and mutants deficient in acetate metabolism, this effect was shown to require acetate-CoA synthetase [acetate:CoA ligase (AMP-forming); EC 6.2.1.1], an enzyme that catalyzes the formation of acetyl-CoA from acetate by an acetyladenylate intermediate. A mutant deficient in this enzyme but retaining the chemotaxis genes was deficient for chemotaxis. Thus, acetyladenylate appears to play a role in generating clockwise rotation at the level of CheY or the motor.
缺失编码传感器以及除CheY之外所有已知胞质趋化蛋白基因的大肠杆菌细胞,在添加乙酸盐后会通过使鞭毛马达顺时针旋转做出可逆反应。通过改变生长条件、使用代谢抑制剂以及乙酸盐代谢缺陷型突变体,结果表明这种效应需要乙酸辅酶A合成酶[乙酸:辅酶A连接酶(AMP形成);EC 6.2.1.1],该酶通过乙酰腺苷酸中间体催化由乙酸盐形成乙酰辅酶A。一个缺乏该酶但保留趋化基因的突变体在趋化方面存在缺陷。因此,乙酰腺苷酸似乎在CheY或马达水平上发挥了产生顺时针旋转的作用。