Structural analysis of bacterial chemotaxis proteins: Components of a dynamic signaling system
Structural analysis of bacterial chemotaxis proteins: Components of a dynamic signaling system
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DOI：
10.1006/jsbi.1998.4034
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发表时间：
1998-12-15
影响因子：
3
通讯作者：
Stock, AM
中科院分区：
文献类型：
--
作者：
Djordjevic, S;Stock, AM
大多数能动的细菌都能够根据化学梯度来指导它们的运动，这种行为被称为趋化性。在肠道细菌中介导趋化性的信号转导系统由一组六种细胞质蛋白组成，所述细胞质蛋白将由跨膜受体家族感知的刺激与由鞭毛马达产生的行为反应偶联。信号转导通过磷酸转移途径发生，该途径涉及组氨酸蛋白激酶CheA和反应调节蛋白CheY，其在磷酸化状态下调节鞭毛旋转的方向。两个辅助蛋白质，CheW和CheZ，和两个受体修饰酶，甲酯酶切布和甲基转移酶CheR，影响磷酰基基团在这一中心途径的流量。本文着重于四个信号蛋白（CheA，CheY，切布，和CheR）的结构特征的MMR或X射线晶体结构已确定。检查蛋白质的信号传导活动，涉及可逆的蛋白质修饰和大分子复合物的瞬时组装。各种数据表明这些蛋白质的构象灵活性，与它们在动态信号通路中的多种作用一致的特征。(C)北京：科学出版社.
Most motile bacteria are capable of directing their movement in response to chemical gradients, a behavior known as chemotaxis. The signal transduction system that mediates chemotaxis in enteric bacteria consists of a set of six cytoplasmic proteins that couple stimuli sensed by a family of transmembrane receptors to behavioral responses generated by the flagellar motors. Signal transduction occurs via a phosphotransfer pathway involving a histidine protein kinase, CheA, and a response regulator protein, CheY, that in its phosphorylated state, modulates the direction of flagellar rotation. Two auxiliary proteins, CheW and CheZ, and two receptor modification enzymes, methylesterase CheB and methyltransferase CheR, influence the flux of phosphoryl groups within this central pathway. This paper focuses on structural characteristics of the four signaling proteins (CheA, CheY, CheB, and CheR) for which MMR or x-ray crystal structures have been determined. The proteins are examined with respect to their signaling activities that involve reversible protein modifications and transient assembly of macromolecular complexes. A variety of data suggest conformational flexibility of these proteins, a feature consistent with their multiple roles in a dynamic signaling pathway. (C) 1998 Academic Press.