4I44

Aer2 poly-HAMP domains: V33G HAMP1 inverted signaling mutant

4I44 の概要

• エントリーDOI: 10.2210/pdb4i44/pdb
• 関連するPDBエントリー: 3LNR 4I3M
• 分子名称: Aerotaxis transducer Aer2, CHLORIDE ION (3 entities in total)
• 機能のキーワード: hamp domain, poly-hamp domains, signal transduction, signal relay, signaling protein
• 由来する生物種: Pseudomonas aeruginosa
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 18976.75

構造登録者

Airola, M.V.,Sukomon, N.,Crane, B.R. (登録日: 2012-11-27, 公開日: 2013-02-27, 最終更新日: 2024-02-28)

主引用文献

Airola, M.V.,Sukomon, N.,Samanta, D.,Borbat, P.P.,Freed, J.H.,Watts, K.J.,Crane, B.R.
HAMP Domain Conformers That Propagate Opposite Signals in Bacterial Chemoreceptors.
Plos Biol., 11:e1001479-e1001479, 2013

PubMed Abstract: HAMP domains are signal relay modules in >26,000 receptors of bacteria, eukaryotes, and archaea that mediate processes involved in chemotaxis, pathogenesis, and biofilm formation. We identify two HAMP conformations distinguished by a four- to two-helix packing transition at the C-termini that send opposing signals in bacterial chemoreceptors. Crystal structures of signal-locked mutants establish the observed structure-to-function relationships. Pulsed dipolar electron spin resonance spectroscopy of spin-labeled soluble receptors active in cells verify that the crystallographically defined HAMP conformers are maintained in the receptors and influence the structure and activity of downstream domains accordingly. Mutation of HR2, a key residue for setting the HAMP conformation and generating an inhibitory signal, shifts HAMP structure and receptor output to an activating state. Another HR2 variant displays an inverted response with respect to ligand and demonstrates the fine energetic balance between "on" and "off" conformers. A DExG motif found in membrane proximal HAMP domains is shown to be critical for responses to extracellular ligand. Our findings directly correlate in vivo signaling with HAMP structure, stability, and dynamics to establish a comprehensive model for HAMP-mediated signal relay that consolidates existing views on how conformational signals propagate in receptors. Moreover, we have developed a rational means to manipulate HAMP structure and function that may prove useful in the engineering of bacterial taxis responses.

PubMed: 23424282
DOI: 10.1371/journal.pbio.1001479

実験手法

X-RAY DIFFRACTION (2.88 Å)