3ZX6

Structure of Hamp(AF1503)-Tsr fusion - Hamp (A291V) mutant

Summary for 3ZX6

• Entry DOI: 10.2210/pdb3zx6/pdb
• Descriptor: HAMP, METHYL-ACCEPTING CHEMOTAXIS PROTEIN I, CHLORIDE ION (3 entities in total)
• Functional Keywords: signaling, hamp domain, tsr receptor, fusion
• Biological source: ARCHAEOGLOBUS FULGIDUS; More
• Cellular location: Cell inner membrane ; Multi- pass membrane protein : P02942
• Total number of polymer chains: 2
• Total formula weight: 72343.04

Authors

Zeth, K.,Ferris, H.U.,Lupas, A.L. (deposition date: 2011-08-08, release date: 2012-02-29, Last modification date: 2023-12-20)

Primary citation

Ferris, H.U.,Zeth, K.,Hulko, M.,Dunin-Horkawicz, S.,Lupas, A.N.
Axial Helix Rotation as a Mechanism for Signal Regulation Inferred from the Crystallographic Analysis of the E. Coli Serine Chemoreceptor.
J.Struct.Biol., 186:349-, 2014

PubMed Abstract: Bacterial chemotaxis receptors are elongated homodimeric coiled-coil bundles, which transduce signals generated in an N-terminal sensor domain across 15-20nm to a conserved C-terminal signaling subdomain. This signal transduction regulates the activity of associated kinases, altering the behavior of the flagellar motor and hence cell motility. Signaling is in turn modulated by selective methylation and demethylation of specific glutamate and glutamine residues in an adaptation subdomain. We have determined the structure of a chimeric protein, consisting of the HAMP domain from Archaeoglobus fulgidus Af1503 and the methyl-accepting domain of Escherichia coli Tsr. It shows a 21nm coiled coil that alternates between two coiled-coil packing modes: canonical knobs-into-holes and complementary x-da, a variant form related to the canonical one by axial rotation of the helices. Comparison of the obtained structure to the Thermotoga maritima chemoreceptor TM1143 reveals that they adopt different axial rotation states in their adaptation subdomains. This conformational change is presumably induced by the upstream HAMP domain and may modulate the affinity of the chemoreceptor to the methylation-demethylation system. The presented findings extend the cogwheel model for signal transmission to chemoreceptors.

PubMed: 24680785
DOI: 10.1016/J.JSB.2014.03.015

Experimental method

X-RAY DIFFRACTION (2.65 Å)