Jiang M, Shao W, Perego M, Hoch J A
Division of Cellular Biology, Department of Molecular and Experimental Medicine, MEM-116, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Mol Microbiol. 2000 Nov;38(3):535-42. doi: 10.1046/j.1365-2958.2000.02148.x.
Protein homology studies identified five kinases potentially capable of phosphorylating the Spo0F response regulator and initiating sporulation in Bacillus subtilis. Two of these kinases, KinA and KinB, were known from previous studies to be responsible for sporulation in laboratory media. In vivo studies of the activity of four of the kinases, KinA, KinC, KinD (ykvD) and KinE (ykrQ), using abrB transcription as an indicator of Spo0A approximately P level, revealed that KinC and KinD were responsible for Spo0A approximately P production during the exponential phase of growth in the absence of KinA and KinB. In vitro, all four kinases dephosphorylated Spo0F approximately P with the production of ATP at approximately the same rate, indicating that they possess approximately equal affinity for Spo0F. All the kinases were expressed during growth and early stationary phase, suggesting that the differential activity observed in growth and sporulation results from differential activation by signal ligands unique to each kinase.
蛋白质同源性研究确定了五种激酶，它们可能能够磷酸化枯草芽孢杆菌中的Spo0F反应调节因子并启动芽孢形成。先前的研究已知其中两种激酶KinA和KinB在实验室培养基中负责芽孢形成。使用abrB转录作为Spo0AP水平的指标，对KinA、KinC、KinD（ykvD）和KinE（ykrQ）这四种激酶的活性进行的体内研究表明，在没有KinA和KinB的情况下，KinC和KinD在生长指数期负责Spo0AP的产生。在体外，所有四种激酶以大致相同的速率使Spo0F~P去磷酸化并产生ATP，表明它们对Spo0F具有大致相等的亲和力。所有激酶在生长和早期稳定期均有表达，这表明在生长和芽孢形成过程中观察到的差异活性是由每种激酶特有的信号配体的差异激活所致。
