A broad-spectrum peptide inhibitor of beta-lactamase identified using phage display and peptide arrays.
Hydrolysis of beta-lactam antibiotics by beta-lactamase enzymes is the most common mechanism of bacterial resistance to these agents. Several small-molecule, mechanism-based inhibitors of beta-lactamases such as clavulanic acid are clinically available although resistance to these inhibitors has been increasing in bacterial populations. In addition, these inhibitors act only on class A beta-lactamases. Here we utilized phage display to identify peptides that bind to the class A beta-lactamase, TEM-1. The binding affinity of one of these peptides was further optimized by the synthesis of peptide arrays using SPOT synthesis technology. After two rounds of optimization, a linear 6-mer peptide with the sequence RRGHYY was obtained. A soluble version of this peptide was synthesized and found to inhibit TEM-1 beta-lactamase with a K(i) of 136 micro M. Surprisingly, the peptide inhibits the class A Bacillus anthracis Bla1 beta-lactamase with a K(i) of 42 micro M and the class C beta-lactamase, P99, with a K(i) of 140 micro M, despite the fact that it was not optimized to bind these enzymes. This peptide may be a useful starting point for the design of non-beta-lactam, broad-spectrum peptidomimetic inhibitors of beta-lactamases.
Huang
Wanzhi
W
Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Beharry
Zanna
Z
Zhang
Zhen
Z
Palzkill
Timothy
T
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D040081:Protein Array Analysis; D013329:Structure-Activity Relationship; D013816:Thermodynamics; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000378:metabolism
D004791:Enzyme Inhibitors; D019151:Peptide Library; D010455:Peptides; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases; C034413:beta-lactamase TEM-1