Kinetic and Thermodynamic Characterization of Human 4-Oxo-l-proline Reductase Catalysis.

ABSTRACT: The enzyme 4-oxo-l-proline reductase (BDH2) has recently been identified in humans. BDH2, previously thought to be a cytosolic (R)-3-hydroxybutyrate dehydrogenase, actually catalyzes the NADH-dependent reduction of 4-oxo-l-proline to cis-4-hydroxy-l-proline, a compound with known anticancer activity. Here we provide an initial mechanistic characterization of the BDH2-catalyzed reaction. Haldane relationships show the reaction equilibrium strongly favors the formation of cis-4-hydroxy-l-proline. Stereospecific deuteration of NADH C4 coupled with mass spectrometry analysis of the reaction established that the pro-S hydrogen is transferred. NADH is co-purified with the enzyme, and a binding kinetics competition assays with NAD⁺ defined dissociation rate

SUBMITTER: Pecaver E 

PROVIDER: S-EPMC11840923 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature