Engineered chemotaxis core signaling units indicate a constrained kinase-off state.

Autor:	Muok AR; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.; Institute for Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, Netherlands., Chua TK; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA., Srivastava M; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.; National Biomedical Center for Advanced ESR Technologies (ACERT), Cornell University, Ithaca, NY 14853, USA., Yang W; Institute for Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, Netherlands., Maschmann Z; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA., Borbat PP; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.; National Biomedical Center for Advanced ESR Technologies (ACERT), Cornell University, Ithaca, NY 14853, USA., Chong J; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA., Zhang S; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA., Freed JH; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.; National Biomedical Center for Advanced ESR Technologies (ACERT), Cornell University, Ithaca, NY 14853, USA., Briegel A; Institute for Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, Netherlands., Crane BR; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA. bc69@cornell.edu.
Jazyk:	angličtina
Zdroj:	Science signaling [Sci Signal] 2020 Nov 10; Vol. 13 (657). Date of Electronic Publication: 2020 Nov 10.
DOI:	10.1126/scisignal.abc1328
Abstrakt:	Bacterial chemoreceptors, the histidine kinase CheA, and the coupling protein CheW form transmembrane molecular arrays with remarkable sensing properties. The receptors inhibit or stimulate CheA kinase activity depending on the presence of attractants or repellants, respectively. We engineered chemoreceptor cytoplasmic regions to assume a trimer of receptor dimers configuration that formed well-defined complexes with CheA and CheW and promoted a CheA kinase-off state. These mimics of core signaling units were assembled to homogeneity and investigated by site-directed spin-labeling with pulse-dipolar electron-spin resonance spectroscopy (PDS), small-angle x-ray scattering, targeted protein cross-linking, and cryo-electron microscopy. The kinase-off state was especially stable, had relatively low domain mobility, and associated the histidine substrate and docking domains with the kinase core, thus preventing catalytic activity. Together, these data provide an experimentally restrained model for the inhibited state of the core signaling unit and suggest that chemoreceptors indirectly sequester the kinase and substrate domains to limit histidine autophosphorylation. (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu