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Updated: Apr 4, 2026

Analysis of the Lipid Composition of Mycobacteria by Thin Layer Chromatography
Published on: April 16, 2021
α-Methyl Acyl CoA Racemase Provides Mycobacterium tuberculosis Catabolic Access to Cholesterol Esters
Rui Lu1, Werner Schmitz2, Nicole S Sampson1
1Department of Chemistry, Stony Brook University , Stony Brook, New York 11794-3400, United States.
Abstract:
Metabolism of cholesterol by Mycobacterium tuberculosis (Mtb) contributes to its pathogenesis. We show that ChsE4-ChsE5 (Rv3504/Rv3505) specifically catalyzes dehydrogenation of the (25S)-3-oxo-cholest-4-en-26-oyl-CoA diastereomer in cholesterol side chain β-oxidation. Thus, a dichotomy between the supply of both 25R and 25S metabolic precursors by upstream cytochrome P450s and the substrate stereospecificity of ChsE4-ChsE5 exists. We reconcile the dilemma of 25R metabolite production by demonstrating that mycobacterial MCR (Rv1143) can efficiently epimerize C25 diastereomers of 3-oxo-cholest-4-en-26-oyl-CoA. Our data suggest that cholesterol and cholesterol ester precursors can converge into a single catabolic pathway, thus widening the metabolic niche in which Mtb survives.
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