A slow, tight-binding inhibitor of the zinc-dependent deacetylase LpxC of lipid A biosynthesis with antibiotic activity comparable to ciprofloxacin.
Journal Article (Journal Article)
The zinc-dependent enzyme LpxC catalyzes the deacetylation of UDP-3-O-acyl-GlcNAc, the first committed step of lipid A biosynthesis. Lipid A is an essential component of the outer membranes of most Gram-negative bacteria, including Escherichia coli, Salmonella enterica, and Pseudomonas aeruginosa, making LpxC an attractive target for antibiotic design. The inhibition of LpxC by a novel N-aroyl-l-threonine hydroxamic acid (CHIR-090) from a recent patent application (International Patent WO 2004/062601 A2 to Chiron and the University of Washington) is reported here. CHIR-090 possesses remarkable antibiotic activity against both E. coli and P. aeruginosa, comparable to that of ciprofloxacin. The biological activity of CHIR-090 is explained by its inhibition of diverse LpxC orthologues at low nanomolar concentrations, including that of Aquifex aeolicus, for which structural information is available. The inhibition of A. aeolicus LpxC by CHIR-090 occurs in two steps. The first step is rapid and reversible, with a K(i) of 1.0-1.7 nM, depending upon the method of assay. The second step involves the conversion of the EI complex with a half-life of about a minute to a tightly bound form. The second step is functionally irreversible but does not result in the covalent modification of the enzyme, as judged by electrospray ionization mass spectrometry. CHIR-090 is the first example of a slow, tight-binding inhibitor for LpxC and may be the prototype for a new generation of LpxC inhibitors with therapeutic applicability.
Full Text
Duke Authors
Cited Authors
- McClerren, AL; Endsley, S; Bowman, JL; Andersen, NH; Guan, Z; Rudolph, J; Raetz, CRH
Published Date
- December 20, 2005
Published In
Volume / Issue
- 44 / 50
Start / End Page
- 16574 - 16583
PubMed ID
- 16342948
Pubmed Central ID
- PMC2742919
International Standard Serial Number (ISSN)
- 0006-2960
Digital Object Identifier (DOI)
- 10.1021/bi0518186
Language
- eng
Conference Location
- United States