Structure and function studies of the orphan cytochrome P450S CYP126A1 and CYP143A1 from the human pathogen mycobacterium tuberculosis

The National Institute of Allergy and Infectious Diseases awarded The University of Akron $538,741 on August 1, 2026, under the Allergy and Infectious Diseases Research program (CFDA 93.855) to conduct structure and function studies of orphan cytochrome P450 enzymes CYP126A1 and CYP143A1 from Mycobacterium tuberculosis.

The research will employ resonance Raman spectroscopy and biochemical analysis to define the structural features of reactive intermediates governing CYP126A1 catalysis, elucidate structural factors determining inhibitory potency of azole-based drug candidates against both enzymes, and identify potential substrate-like ligands of CYP143A1 through high-throughput screening coupled with spectroscopic and biochemical characterization. These findings are intended to establish a foundation for rational design of next-generation antitubercular agents targeting P450-mediated pathways.

The award supports research at The University of Akron, Akron, Ohio, with a period of performance from August 1, 2026, through July 31, 2029. The assistance type is a Project Grant. This is a competitive research award under NIH's program to support biomedical research and research training in infectious diseases and related areas at public and private nonprofit institutions.

Abstract

The cytochrome P450 (CYP) superfamily comprises heme-containing monooxygenases that catalyze a wide range of oxidative reactions essential for metabolism and survival across all domains of life. In mycobacterium tuberculosis (MTB), several P450 enzymes are known to be critical for bacterial viability and virulence, highlighting them as promising drug targets for tuberculosis therapy. Among these, CYP126A1 and CYP143A1 are two highly conserved "orphan" enzymes whose physiological substrates and biochemical functions remain undefined. Preliminary evidence suggests that CYP126A1 interacts with azole-based inhibitors and polycyclic substrates, whereas CYP143A1 possesses an unusually narrow active-site channel resembling that of a cholesterol hydroxylase, suggesting distinct roles in lipid or sterol metabolism. The proposed research seeks to elucidate the structure and function relationships of two mycobacterium tuberculosis cytochrome P450 enzymes, CYP126A1 and CYP143A1, through detailed spectroscopic and biochemical analyses, primarily employing resonance raman spectroscopy. Specifically, we aim to define the structural features of reactive intermediates that govern CYP126A1 catalysis, elucidate the structural factors that determine the inhibitory potency of azole-based drug candidates against both CYP126A1 and CYP143A1, and identify potential substrate-like ligands of CYP143A1 through high-throughput screening (HTS) coupled with spectroscopic and biochemical characterization. Collectively, these studies will provide a comprehensive understanding of how these enzymes contribute to m. Tuberculosis metabolism and pathogenesis and will establish a foundation for the rational design of next-generation antitubercular agents that selectively target P450-mediated pathways.