7L6C

Crystal Structure of Enoyl-[acyl-carrier-protein] reductase InhA from Mycobacterium abscessus in complex with NAD

Summary for 7L6C

• Entry DOI: 10.2210/pdb7l6c/pdb
• Related: 7KLI
• Descriptor: Enoyl-[acyl-carrier-protein] reductase [NADH], NICOTINAMIDE-ADENINE-DINUCLEOTIDE, 1,2-ETHANEDIOL, ... (5 entities in total)
• Functional Keywords: ssgcid, enoyl-[acyl-carrier-protein] reductase, inha, mab_2722c, nad, structural genomics, seattle structural genomics center for infectious disease, oxidoreductase
• Biological source: Mycobacteroides abscessus (strain ATCC 19977 / DSM 44196 / CIP 104536 / JCM 13569 / NCTC 13031 / TMC 1543)
• Total number of polymer chains: 4
• Total formula weight: 121650.09

Authors

Seattle Structural Genomics Center for Infectious Disease (SSGCID) (deposition date: 2020-12-23, release date: 2021-01-13, Last modification date: 2023-10-18)

Primary citation

Alcaraz, M.,Roquet-Baneres, F.,Leon-Icaza, S.A.,Abendroth, J.,Boudehen, Y.M.,Cougoule, C.,Edwards, T.E.,Kremer, L.
Efficacy and Mode of Action of a Direct Inhibitor of Mycobacterium abscessus InhA.
Acs Infect Dis., 8:2171-2186, 2022

PubMed Abstract: There is an unmet medical need for effective treatments against pulmonary infections, to which cystic fibrosis (CF) patients are particularly vulnerable. Recent studies showed that the antitubercular drug isoniazid is inactive against due to the incapacity of the catalase-peroxidase to convert the pro-drug into a reactive metabolite that inhibits the enoyl-ACP reductase InhA. To validate InhA as a druggable target in , we assayed the activity of NITD-916, a 4-hydroxy-2-pyridone lead candidate initially described as a direct inhibitor of InhA that bypasses KatG bioactivation in . The compound displayed low MIC values against rough and smooth clinical isolates in vitro and significantly reduced the bacterial burden inside human macrophages. Moreover, treatment with NITD-916 reduced the number and size of intracellular mycobacterial cords, regarded as markers of the severity of the infection. Importantly, NITD-916 significantly lowered the burden in CF-derived lung airway organoids. From a mechanistic perspective, NITD-916 abrogated de novo synthesis of mycolic acids and NITD-916-resistant spontaneous mutants harbored point mutations in InhA at residue 96. That NITD-916 targets InhA directly without activation requirements was confirmed genetically and by resolving the crystal structure of the protein in complex with NADH and NITD-916. These findings collectively indicate that InhA is an attractive target to be exploited for future chemotherapeutic developments against this difficult-to-treat mycobacterium and highlight the potential of NITD-916 derivatives for further evaluation in preclinical settings.

PubMed: 36107992
DOI: 10.1021/acsinfecdis.2c00314

Experimental method

X-RAY DIFFRACTION (1.85 Å)