Abstract

The recently identified glycyl radical enzyme (GRE) homologue choline trimethylamine-lyase (CutC) participates in the anaerobic conversion of choline to trimethylamine (TMA), a widely distributed microbial metabolic transformation that occurs in the human gut and is linked to disease. The proposed biochemical function of CutC, C-N bond cleavage, represents new reactivity for the GRE family. Here we describe the in vitro characterization of CutC and its activating protein CutD. We have observed CutD-mediated formation of a glycyl radical on CutC using EPR spectroscopy and have demonstrated that activated CutC processes choline to trimethylamine and acetaldehyde. Surveys of potential alternate CutC substrates uncovered a strict specificity for choline. Homology modeling and mutagenesis experiments revealed essential CutC active site residues. Overall, this work establishes that CutC is a GRE of unique function and a molecular marker for anaerobic choline metabolism.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.