Beta-lactamase stability of imipenem

Area of Science:

• Microbiology
• Pharmacology
• Biochemistry

Background:

• Beta-lactamase enzymes confer resistance to beta-lactam antibiotics.
• Understanding antibiotic-beta-lactamase interactions is crucial for combating antimicrobial resistance.

Purpose of the Study:

• To compare the stability and interactions of imipenem with various beta-lactamases against other beta-lactam antibiotics.
• To evaluate imipenem's resistance profile to different classes of beta-lactamase enzymes.

Main Methods:

• Analysis of imipenem's interaction with representative beta-lactamases (penicillinases, cephalosporinases, and novel beta-lactamases).
• Comparative study with cefazolin, cefuroxime, cefoxitin, cefotaxime, ceftazidime, mezlocillin, piperacillin, and penicillin G.

Main Results:

• Group A enzymes (penicillinases) hydrolyzed penicillins and early cephalosporins.
• Group B enzymes hydrolyzed newer cephalosporins and cephamycins but not imipenem.
• Group C enzymes hydrolyzed newer cephalosporins but not cephamycins or imipenem.
• Imipenem exhibited moderate affinity but no detectable hydrolysis by any tested beta-lactamase.

Conclusions:

• Imipenem demonstrates broad stability against a range of clinically significant beta-lactamases.
• Imipenem's resistance to hydrolysis suggests its potential utility against infections caused by beta-lactamase-producing bacteria.