![]() This discovery led to the realization that bacterial cells are far more organized than was previously anticipated. In their seminal paper >20 years ago, Maddock and Shapiro showed that bacterial chemoreceptor clusters are specifically localized at cell poles in Escherichia coli 7. These intricate signal transduction complexes regulate flagellar rotation, thereby controlling the swimming direction of bacteria 10, 11. The assembly of individual sensory proteins into large clusters provides high sensitivity, and allows the cell to integrate various environmental signals into a unified output 8, 9. Together with specific kinases, phosphatases and receptor-modulating proteins, they form large stable sensory clusters. A classic example is the polar localization pattern of the chemotactic sensory complexes 6, 7.īacteria sense their surrounding by transmembrane or cytoplasmic chemoreceptor proteins that form dimers, which assemble into trimers. Despite its importance, we still do not have a good understanding by which mechanisms proteins are sequestered to the bacterial cell poles. In rod-shaped bacteria, the cell pole is such an area to which a large number of proteins are recruited 2, 3, 4, 5. These findings demonstrate that the intrinsic shape of transmembrane proteins can determine their cellular localization.Ĭells rely on a strict cellular organization for their growth and function, and many biochemical processes are confined to specific areas in the cell 1, 2. By constructing specific amino-acid substitutions, we demonstrate that the preference for strongly curved membranes arises from the curved shape of chemoreceptor trimer of dimers. Localization appears to be an intrinsic property of the protein complex and does not rely on chemoreceptor clustering, as was previously shown for Escherichia coli. This preference was confirmed by accumulation at non-septal curved membranes. ![]() Here we show that the classical chemoreceptor TlpA of Bacillus subtilis does not localize according to the consensus stochastic nucleation mechanism but accumulates at strongly curved membrane areas generated during cell division. A typical example is the assembly of bacterial chemoreceptors at cell poles. In most cases, we have a poor understanding of the underlying mechanisms. The intricate structure of prokaryotic and eukaryotic cells depends on the ability to target proteins to specific cellular locations. ![]()
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