Design and exploration of novel boronic acid inhibitors reveals important interactions with a clavulanic acid-resistant sulfhydryl-variable (SHV) beta-lactamase.Winkler, M.L., Rodkey, E.A., Taracila, M.A., Drawz, S.M., Bethel, C.R., Papp-Wallace, K.M., Smith, K.M., Xu, Y., Dwulit-Smith, J.R., Romagnoli, C., Caselli, E., Prati, F., van den Akker, F., Bonomo, R.A.
(2013) J.Med.Chem. 56: 1084-1097
- PubMed: 23252553
- DOI: 10.1021/jm301490d
- PubMed Abstract:
Inhibitor resistant (IR) class A β-lactamases pose a significant threat to many current antibiotic combinations. The K234R substitution in the SHV β-lactamase, from Klebsiella pneumoniae , results in resistance to ampicillin/clavulanate. After site-s ...
Inhibitor resistant (IR) class A β-lactamases pose a significant threat to many current antibiotic combinations. The K234R substitution in the SHV β-lactamase, from Klebsiella pneumoniae , results in resistance to ampicillin/clavulanate. After site-saturation mutagenesis of Lys-234 in SHV, microbiological and biochemical characterization of the resulting β-lactamases revealed that only -Arg conferred resistance to ampicillin/clavulanate. X-ray crystallography revealed two conformations of Arg-234 and Ser-130 in SHV K234R. The movement of Ser-130 is the principal cause of the observed clavulanate resistance. A panel of boronic acid inhibitors was designed and tested against SHV-1 and SHV K234R. A chiral ampicillin analogue was discovered to have a 2.4 ± 0.2 nM K(i) for SHV K234R; the chiral ampicillin analogue formed a more complex hydrogen-bonding network in SHV K234R vs SHV-1. Consideration of the spatial position of Ser-130 and Lys-234 and this hydrogen-bonding network will be important in the design of novel antibiotics targeting IR β-lactamases.
Department of Microbiology and Molecular Biology, Case Western Reserve University, Cleveland, Ohio 44106, USA.