Structure and electrostatic property of cytoplasmic domain of ZntB transporter

Kemin Tan, Alicia Sather, Janice L. Robertson, Shiu Moy, Benoît Roux, Andrzej Joachimiak

Research output: Contribution to journalArticlepeer-review

11 Scopus citations

Abstract

ZntB is the distant homolog of CorA Mg2+ transporter within the metal ion transporter superfamily. It was early reported that the ZntB from Salmonella typhimurium facilitated efflux of Zn2+ and Cd 2+, but not Mg2+. Here, we report the 1.90 Å crystal structure of the intracellular domain of ZntB from Vibrio parahemolyticus. The domain forms a funnel-shaped homopentamer that is similar to the full-length CorA from Thermatoga maritima, but differs from two previously reported dimeric structures of truncated CorA intracellular domains. However, no Zn2+ or Cd2+ binding sites were identified in the high-resolution structure. Instead, 25 well-defined Cl- ions were observed and some of these binding sites are highly conserved within the ZntB family. Continuum electrostatics calculations suggest that the central pore of the funnel is highly attractive for cations, especially divalents. The presence of the bound Cl- ions increases the stability of cations along the pore suggesting they could be important in enhancing cation transport.

Original languageEnglish
Pages (from-to)2043-2052
Number of pages10
JournalProtein Science
Volume18
Issue number10
DOIs
StatePublished - Oct 2009

Keywords

  • Cl ions
  • CorA
  • Electrostatic
  • Pentamer
  • Structure
  • Transporter
  • ZntB

Fingerprint

Dive into the research topics of 'Structure and electrostatic property of cytoplasmic domain of ZntB transporter'. Together they form a unique fingerprint.

Cite this