Abstract
Mitochondrial trifunctional protein (MTP) catalyzes three consecutive step reactions in the β-oxidation of long-chain fatty acids, and plays important roles in control and regulation of the β-oxidation. We overexpressed in E. coli, and purified the MTP as a Mistic fusion protein, which was found to be an α 2β 2 protein complex and characterized with kinetic studies. Trimetazidine, used for treating chronic stable angina, has been proposed to be an inhibitor of the β-subunit. We found that a catalytic cysteine residue C105 was labeled by trimetazidine through MS/MS analysis of a trimetazidine-labeled peptide fragment obtained from pepsin digested β-subunit inactivated by trimetazidine. The MTP β-subunit was then comparatively studied with monofunctional 3-ketoacyl-CoA thiolase through sequence alignment, site-directed mutagenesis, characterization of variant enzymes with kinetic studies, and homology modeling. The results indicate that the catalytic residues of the MTP β-subunit are positioned in the active site similarly to those of monofunctional 3-ketoacyl-CoA thiolase.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
