PMID: 28594172

Authors:

Liu F, Dawadi S, Maize KM, Dai R, Park SW, Schnappinger D, Finzel BC, Aldrich CC

Title:

Structure-Based Optimization of Pyridoxal 5'-Phosphate-Dependent Transaminase Enzyme (BioA) Inhibitors that Target Biotin Biosynthesis in Mycobacterium tuberculosis.

Journal:

J Med Chem. 2017 Jul 13;60(13):5507-5520. doi: 10.1021/acs.jmedchem.7b00189. Epub, 2017 Jun 22.

Abstract:

The pyridoxal 5'-phosphate (PLP)-dependent transaminase BioA catalyzes the second step in the biosynthesis of biotin in Mycobacterium tuberculosis (Mtb) and is an essential enzyme for bacterial survival and persistence in vivo. A promising BioA inhibitor 6 containing an N-aryl, N'-benzoylpiperazine scaffold was previously identified by target-based whole-cell screening. Here, we explore the structure-activity relationships (SAR) through the design, synthesis, and biological evaluation of a systematic series of analogues of the original hit using a structure-based drug design strategy, which was enabled by cocrystallization of several analogues with BioA. To confirm target engagement and discern analogues with off-target activity, each compound was evaluated against wild-type (WT) Mtb in biotin-free and -containing medium as well as BioA under- and overexpressing Mtb strains. Conformationally constrained derivative 36 emerged as the most potent analogue with a KD of 76 nM against BioA and a minimum inhibitory concentration of 1.7 muM (0.6 mug/mL) against Mtb in biotin-free medium.