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Updated: Jul 3, 2026

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
Functional characterization of the Shigella dysenteriae heme ABC transporter
Kimberly A Burkhard1, Angela Wilks
1Department of Pharmaceutical Sciences, School of Pharmacy, 20 Penn Street, University of Maryland, Baltimore, Maryland 21201-1140, USA.
Abstract:
The heme ATP binding cassette (ABC) transporter, ShuUV, of Shigella dysenteriae has been incorporated into proteoliposomes. Functional characterization of ShuUV revealed that ATP hydrolysis and transport of heme from the periplasmic binding protein, ShuT, to the cytoplasmic binding protein, ShuS, are coupled. Site-directed mutagenesis of ShuT residues proposed to be required for stabilization of the complex abolished heme transport. Furthermore, residues His-252 and His-262, located in the translocation channel of ShuU, were required for the release of heme from ShuT and translocation to ShuS. The initial functional characterization of an in vitro heme uptake system provides a platform for future spectroscopic studies.
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