Kinetic and structural studies of the reaction of Escherichia coli dihydrodipicolinate synthase with (S)-2-bromopropionate.

ABSTRACT: Dihydrodipicolinate synthase (DHDPS) catalyzes the first committed step in the lysine-biosynthetic pathway converting pyruvate and L-aspartate-β-semialdehyde to dihydrodipicolinate. Kinetic studies indicate that the pyruvate analog (S)-2-bromopropionate inactivates the enzyme in a pseudo-first-order process. An initial velocity pattern indicates that (S)-2-bromopropionate is a competitive inhibitor versus pyruvate, with an inhibition constant of about 8 mM. Crystals of DHDPS complexed with (S)-2-bromopropionate formed in a solution consisting of 50 mM HEPES pH 7.5, 18% polyethylene glycol 3350, 8 mM spermidine, 0.2 M sodium tartrate and 5.0 mg ml^-1 DHDPS. The crystals diffracted to 2.15 Å resolution and belonged to space group P1. The crystal structure confirms the displacement

SUBMITTER: Chooback L 

PROVIDER: S-EPMC9248844 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature