Related Experiment Videos
Thiamine biosynthesis in Escherichia coli: isolation and initial characterisation of the ThiGH complex
Roberta Leonardi1, Shirley A Fairhurst, Marco Kriek
1Department of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
Abstract:
In Escherichia coli, two of the proteins required for the biosynthesis of the thiazole moiety of thiamine (vitamin B(1)) are ThiG and ThiH, encoded as part of the thiCEFSGH operon. In this study, a C-terminally hexahistidine-tagged ThiH (ThiH-His) was expressed in E. coli as a soluble protein from thiGH-His-tag and thiFSGH-His-tag-bearing plasmids. When isolated under anaerobic conditions, ThiG and ThiH-His co-purify as a large multimeric non-covalent complex. Electron paramagnetic resonance and UV-visible spectroscopy together with iron and sulfide analyses revealed the presence of an iron-sulfur cluster within this complex.