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Publication Abstract from PubMed

Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 muM and a measured Ki of 1.8 muM and displayed a dose-responsive antibiotic activity toward Escherichia coli. L-Captopril is also a competitive inhibitor of NmDapE with a Ki of 2.8 muM. To examine the nature of the interaction of L-captopril with the dinuclear active site of DapE, we have obtained electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) data for the enzymatically hyperactive Co(II)-substituted forms of both HiDapE and NmDapE. EPR and MCD data indicate that the two Co(II) ions in DapE are antiferromagnetically coupled, yielding an S = 0 ground state, and suggest a thiolate bridge between the two metal ions. Verification of a thiolate-bridged dinuclear complex was obtained by determining the three-dimensional X-ray crystal structure of NmDapE in complex with L-captopril at 1.8 A resolution. Combination of these data provides new insights into binding of L-captopril to the active site of DapE enzymes as well as important inhibitor-active site residue interaction's. Such information is critical for the design of new, potent inhibitors of DapE enzymes.

Inhibition of the dapE-Encoded N-Succinyl-L,L-diaminopimelic Acid Desuccinylase from Neisseria meningitidis by L-Captopril.,Starus A, Nocek B, Bennett B, Larrabee JA, Shaw DL, Sae-Lee W, Russo MT, Gillner DM, Makowska-Grzyska M, Joachimiak A, Holz RC Biochemistry. 2015 Aug 11;54(31):4834-44. doi: 10.1021/acs.biochem.5b00475. Epub , 2015 Aug 3. PMID:26186504^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.