Structural highlights
Publication Abstract from PubMed
Hymeglusin (1233A, F244, L-659-699) is established as a specific beta-lactone inhibitor of eukaryotic hydroxymethylglutaryl-CoA synthase (HMGCS). Inhibition results from formation of a thioester adduct to the active site cysteine. In contrast, the effects of hymeglusin on bacterial HMG-CoA synthase, mvaS, have been minimally characterized. Hymeglusin blocks growth of Enterococcus faecalis. After removal of the inhibitor from culture media, a growth curve inflection point at 3.1 h is observed (vs 0.7 h for the uninhibited control). Upon hymeglusin inactivation of purified E. faecalis mvaS, the thioester adduct is more stable than that measured for human HMGCS. Hydroxylamine cleaves the thioester adduct; substantial enzyme activity is restored at a rate that is 8-fold faster for human HMGCS than for mvaS. Structural results explain these differences in enzyme-inhibitor thioester adduct stability and solvent accessibility. The E. faecalis mvaS-hymeglusin cocrystal structure (1.95 A) reveals virtually complete occlusion of the bound inhibitor in a narrow tunnel that is largely sequestered from bulk solvent. In contrast, eukaryotic (Brassica juncea) HMGCS binds hymeglusin in a more solvent-exposed cavity.
Biochemical and structural basis for inhibition of Enterococcus faecalis hydroxymethylglutaryl-CoA synthase, mvaS, by hymeglusin.,Skaff DA, Ramyar KX, McWhorter WJ, Barta ML, Geisbrecht BV, Miziorko HM Biochemistry. 2012 Jun 12;51(23):4713-22. doi: 10.1021/bi300037k. Epub 2012 May, 25. PMID:22510038[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Skaff DA, Ramyar KX, McWhorter WJ, Barta ML, Geisbrecht BV, Miziorko HM. Biochemical and structural basis for inhibition of Enterococcus faecalis hydroxymethylglutaryl-CoA synthase, mvaS, by hymeglusin. Biochemistry. 2012 Jun 12;51(23):4713-22. doi: 10.1021/bi300037k. Epub 2012 May, 25. PMID:22510038 doi:http://dx.doi.org/10.1021/bi300037k
