Structural basis for imipenem inhibition of class C beta-lactamases.
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ABSTRACT:
SUBMITTER: Beadle BM
PROVIDER: S-EPMC132770 | biostudies-literature | 2002 Dec
REPOSITORIES: biostudies-literature
Publications
Structural basis for imipenem inhibition of class C beta-lactamases.
Beadle Beth M BM Shoichet Brian K BK
Antimicrobial agents and chemotherapy 20021201 12
To determine how imipenem inhibits the class C beta-lactamase AmpC, the X-ray crystal structure of the acyl-enzyme complex was determined to a resolution of 1.80 A. In the complex, the lactam carbonyl oxygen of imipenem has flipped by approximately 180 degrees compared to its expected position; the electrophilic acyl center is thus displaced from the point of hydrolytic attack. This conformation resembles that of imipenem bound to the class A enzyme TEM-1 but is different from that of moxalactam ...[more]
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