The Escherichia coli ynfEFGHI operon encodes polypeptides which are paralogues of dimethyl sulfoxide reductase (DmsABC)

• Published in: Archives of biochemistry and biophysics 2003-10, Vol.418 (2), p.205-216
• Main Authors: Lubitz, Shannon P, Weiner, Joel H
• Format: Article
• Language: English
• Subjects: Anaerobic respiration; Anaerobiosis - genetics; Cell Membrane - chemistry; Cell Membrane - enzymology; Cell Membrane - genetics; Cell Membrane - metabolism; Chimeric enzyme; Dimethyl Sulfoxide - metabolism; Dimethyl sulfoxide reductase; Escherichia - enzymology; Escherichia - genetics; Escherichia - growth & development; Escherichia - metabolism; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Hydroxypyridine N-oxide; Inclusion bodies; Iron-Sulfur Proteins; Operon - genetics; Oxidoreductases - chemistry; Oxidoreductases - classification; Oxidoreductases - genetics; Oxidoreductases - metabolism; Peptides - chemistry; Peptides - classification; Peptides - genetics; Peptides - metabolism; Recombinant Proteins - chemistry; Recombinant Proteins - classification; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Transcription, Genetic - genetics; Trimethylamine N-oxide reductase
• ISSN: 0003-9861; 1096-0384
• DOI: 10.1016/j.abb.2003.08.008

The ynfEFGHI operon is a paralogue of the Escherichia coli dmsABC operon. ynfE and ynfF are paralogues of dmsA. ynfG and ynfH are paralogues of dmsB and dmsC, respectively. YnfI ( dmsD) has no dms paralogue. YnfE/F and YnfG could be detected by immunoblotting with anti-DmsAB antibodies when expressed under the control of a tac or dms promoter. Cells harbouring ynfFGH on a multicopy plasmid supported anaerobic growth with dimethyl sulfoxide (DMSO) as respiratory oxidant in a dmsABC deletion, suggesting that YnfFGH forms a heterotimeric enzyme complex similar to DmsABC. Exchange of DmsC by YnfH (DmsAB-YnfH) resulted in membrane localization, anaerobic growth on DMSO, and binding of 2- n-heptyl 4-hydroxyquinoline-N-oxide, indicating that YnfH was a competent anchor. YnfG can also replace DmsB as the electron transfer subunit and assembled [Fe–S] clusters as judged by electron paramagnetic resonance spectroscopy. YnfE and/or YnfF could not form a functional complex with DmsBC and expression of YnfE prevented the accumulation of YnfFGH.