Structure and Function of the Bacterial Heterodimeric ABC Transporter CydDC: Stimulation of the ATPase Activity by Thiol and Heme Compounds

Yamashita, Masao and Shepherd, Mark and Booth, Wesley I and Xie, Hao and Postis, Vincent and Nyathi, Yvonne and Tzokov, Svetomir and Poole, Robert K and Baldwin, Stephen A and Bullough, Per A (2014) Structure and Function of the Bacterial Heterodimeric ABC Transporter CydDC: Stimulation of the ATPase Activity by Thiol and Heme Compounds. The Journal of biological chemistry, 289 . pp. 23177-23188. ISSN 1083-351X. (doi:https://doi.org/10.1074/jbc.M114.590414) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided. (Contact us about this Publication)
Official URL
http://dx.doi.org/10.1074/jbc.M114.590414

Abstract

In Escherichia coli, the biogenesis of both cytochrome bd-type quinol oxidases and periplasmic cytochromes requires the ABC- type cysteine/glutathione (GSH) transporter, CydDC. Recombinant CydDC was purified as a heterodimer and found to be an active ATPase both in soluble form with detergent and when reconstituted into a lipid environment. Two dimensional crystals of CydDC were analysed by electron cryomicrosopy and the protein was shown to be made up of two non-identical domains corresponding to the putative CydD and CydC subunits, with dimensions characteristic of other ABC transporters. CydDC binds heme b. Detergent-solubilized CydDC appears to adopt at least two structural states, each associated with a characteristic level of bound heme. The purified protein in detergent showed a weak basal ATPase activity (ca. 100 nmol Pi/min/mg) that was stimulated approximately three-fold by various thiol compounds, suggesting that CydDC could act as a thiol transporter. The presence of heme (either intrinsic or added in the form of hemin) led to a further enhancement of thiol-stimulated ATPase activity although a large excess of heme inhibited activity. Similar responses of the ATPase activity were observed with CydDC reconstituted into E. coli lipids. These results suggest that heme may have a regulatory role in CydDC mediated transmembrane thiol transport.

Item Type: Article
Uncontrolled keywords: ABC Transporter; Bacterial Metabolism; Membrane Protein; Membrane Transporter Reconstitution; Microbiology; Protein Structure; Structural Biology; Transporter
Subjects: Q Science
Q Science > Q Science (General)
Divisions: Faculties > Sciences > School of Biosciences
Depositing User: Mark Shepherd
Date Deposited: 07 Jul 2014 09:18 UTC
Last Modified: 05 Jan 2015 12:45 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/41697 (The current URI for this page, for reference purposes)
  • Depositors only (login required):