JAC Advance Access originally published online on January 19, 2005
Journal of Antimicrobial Chemotherapy 2005 55(2):252-255; doi:10.1093/jac/dkh550
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
JAC vol.55 no.2 © The British Society for Antimicrobial Chemotherapy 2005; all rights reserved
A specific peptide inhibitor of the class B metallo-ß-lactamase L-1 from Stenotrophomonas maltophilia identified using phage display
Centre de Recherche sur la Fonction, Structure et Ingénierie des Protéines, Faculté de Médecine, Pavillon Charles-Eugène-Marchand, Université Laval, Sainte-Foy, Québec, Canada G1K 7P4
* Corresponding author. Tel: +1-418-656-3070; Fax: +1-418-656-7176; Email: rclevesq{at}rsvs.ulaval.ca
Objectives: In Gram-negative bacteria, resistance to ß-lactam antibiotics and to known inhibitors mediated by metallo-ß-lactamases is a major concern and a serious threat to public health. Since no clinically useful inhibitors are available against class B metallo-ß-lactamases, the aim of the study was to identify peptides as inhibitors.
Methods: The L-1 metalloenzyme from Stenotrophomonas maltophilia was cloned, over-expressed, purified to homogeneity and used in screening of peptide libraries by phage display with a selective and competitive biopanning assay. This was based upon the high affinity of L-1 for cefoxitin and its slow hydrolysis.
Results: From six peptides, the consensus sequence Cys-Val-His-Ser-Pro-Asn-Arg-Glu-Cys was identified as a promising inhibitor of L-1 hydrolytic activity. This peptide showed a mixed inhibition of L-1 with a Ki competitive of 16 ± 4 µM and a Ki uncompetitive of 9 ± 1 µM. The same peptide was prepared without flanking Cys residues and demonstrated no detectable inhibition of L-1 hydrolytic activity with nitrocefin as a substrate. These data confirmed the importance of the peptide conformation for the inhibition of L-1 hydrolytic activity. Further analysis revealed rescue by Zn2+ ions. The mixed inhibition indicated peptide binding near the active site of L-1 and blocking of zinc atoms for optimal conformation in the pocket of the active site.
Conclusion: This is the first report of a peptide inhibitor for Class B metallo-ß-lactamases. It will be used as a lead to identify more potent small molecule inhibitors via peptidomimetics.
Keywords: L-1 ß-lactamase , selective biopanning , ß-lactamase inhibitors
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  C. Paradis-Bleau, F. Sanschagrin, and R. C. Levesque Peptide inhibitors of the essential cell division protein FtsA Protein Eng. Des. Sel., February 1, 2005; 18(2): 85 - 91. [Abstract] [Full Text] [PDF]
|
|