PDBsum entry 4git

Hydrolase

PDB id: 4git

Contents

Protein chains

92 a.a.

Ligands

SO4 ×2

Waters ×4

References listed in PDB file

Key reference

• Title: Structural basis for DNA-Mediated allosteric regulation facilitated by the aaa+ module of lon protease.
• Authors: A.Y.Lee, Y.D.Chen, Y.Y.Chang, Y.C.Lin, C.F.Chang, S.J.Huang, S.H.Wu, C.H.Hsu.
• Ref.: Acta Crystallogr D Biol Crystallogr, 2014, 70, 218-230. [DOI no: 10.1107/S139900471302631X]
• PubMed id: 24531457

Abstract

Lon belongs to a unique group of AAA(+) proteases that bind DNA. However, the DNA-mediated regulation of Lon remains elusive. Here, the crystal structure of the α subdomain of the Lon protease from Brevibacillus thermoruber (Bt-Lon) is presented, together with biochemical data, and the DNA-binding mode is delineated, showing that Arg518, Arg557 and Arg566 play a crucial role in DNA binding. Electrostatic interactions contributed by arginine residues in the AAA(+) module are suggested to be important to DNA binding and allosteric regulation of enzymatic activities. Intriguingly, Arg557, which directly binds DNA in the α subdomain, has a dual role in the negative regulation of ATPase stimulation by DNA and in the domain-domain communication in allosteric regulation of Bt-Lon by substrate. In conclusion, structural and biochemical evidence is provided to show that electrostatic interaction in the AAA(+) module is important for DNA binding by Lon and allosteric regulation of its enzymatic activities by DNA and substrate.