Kentner David, Sourjik Victor
Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany.
Curr Opin Microbiol. 2006 Dec;9(6):619-24. doi: 10.1016/j.mib.2006.10.012. Epub 2006 Oct 24.
Sensory complexes in bacterial chemotaxis are organized in large clusters, building complex signal-processing machinery. Interactions among chemoreceptors are the main determinant of cluster formation and create an allosteric network that is able to integrate and amplify stimuli, before transmitting the signal to downstream proteins. Association of the other proteins with the receptor cluster creates a signalling scaffold, which enhances the efficiency and specificity of the pathway. Clusters localize to specific locations inside the cell, perhaps to ensure their proper distribution during cell division. Clustering is conserved among all studied prokaryotic chemotaxis systems and exemplifies a growing number of bacterial pathways with a reported sub-cellular spatial organization. Moreover, because allostery provides a simple mechanism to achieve very high response sensitivity, it is probable that clustering-based signal amplification is not limited to bacterial chemotaxis but also exists in other prokaryotic and eukaryotic pathways.
细菌趋化作用中的感觉复合体以大簇的形式组织起来，构建了复杂的信号处理机制。化学感受器之间的相互作用是簇形成的主要决定因素，并创建了一个变构网络，该网络能够在将信号传递给下游蛋白质之前整合和放大刺激。其他蛋白质与受体簇的结合形成了一个信号支架，提高了信号通路的效率和特异性。簇定位于细胞内的特定位置，这可能是为了确保它们在细胞分裂过程中的正确分布。在所有研究的原核生物趋化系统中，簇化现象都是保守的，并且是越来越多具有报道的亚细胞空间组织的细菌信号通路的例证。此外，由于变构提供了一种实现非常高响应灵敏度的简单机制，基于簇的信号放大很可能不仅限于细菌趋化作用，也存在于其他原核生物和真核生物信号通路中。
