5EPV

Histidine kinase domain from the LOV-HK blue-light receptor from Brucella abortus

Summary for 5EPV

• Entry DOI: 10.2210/pdb5epv/pdb
• Related: 3T50
• Descriptor: Blue-light-activated histidine kinase, PHOSPHOMETHYLPHOSPHONIC ACID ADENYLATE ESTER, MAGNESIUM ION (3 entities in total)
• Functional Keywords: histidine kinase, hwe family, s-sad phasing, multi-crystal data collection, transferase
• Biological source: Brucella abortus
• Total number of polymer chains: 4
• Total formula weight: 106489.15

Authors

Rinaldi, J.,Guimaraes, B.G.,Legrand, P.,Thompson, A.,Paris, G.,Goldbaum, F.A.,Klinke, S. (deposition date: 2015-11-12, release date: 2016-02-24, Last modification date: 2024-03-06)

Primary citation

Rinaldi, J.,Arrar, M.,Sycz, G.,Cerutti, M.L.,Berguer, P.M.,Paris, G.,Estrin, D.A.,Marti, M.A.,Klinke, S.,Goldbaum, F.A.
Structural Insights into the HWE Histidine Kinase Family: The Brucella Blue Light-Activated Histidine Kinase Domain.
J.Mol.Biol., 428:1165-1179, 2016

PubMed Abstract: In response to light, as part of a two-component system, the Brucella blue light-activated histidine kinase (LOV-HK) increases its autophosphorylation, modulating the virulence of this microorganism. The Brucella histidine kinase (HK) domain belongs to the HWE family, for which there is no structural information. The HWE family is exclusively present in proteobacteria and usually coupled to a wide diversity of light sensor domains. This work reports the crystal structure of the Brucella HK domain, which presents two different dimeric assemblies in the asymmetric unit: one similar to the already described canonical parallel homodimers (C) and the other, an antiparallel non-canonical (NC) dimer, each with distinct relative subdomain orientations and dimerization interfaces. Contrary to these crystallographic structures and unlike other HKs, in solution, the Brucella HK domain is monomeric and still active, showing an astonishing instability of the dimeric interface. Despite this instability, using cross-linking experiments, we show that the C dimer is the functionally relevant species. Mutational analysis demonstrates that the autophosphorylation activity occurs in cis. The different relative subdomain orientations observed for the NC and C states highlight the large conformational flexibility of the HK domain. Through the analysis of these alternative conformations by means of molecular dynamics simulations, we also propose a catalytic mechanism for Brucella LOV-HK.

PubMed: 26851072
DOI: 10.1016/j.jmb.2016.01.026

Experimental method

X-RAY DIFFRACTION (2.51 Å)