Kinetic Studies on CphA Mutants Reveal the Role of the P158-P172 Loop in Activity versus Carbapenems.
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ABSTRACT:
SUBMITTER: Bottoni C
PROVIDER: S-EPMC4862501 | biostudies-literature | 2016 May
REPOSITORIES: biostudies-literature
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Kinetic Studies on CphA Mutants Reveal the Role of the P158-P172 Loop in Activity versus Carbapenems.
Bottoni Carlo C Perilli Mariagrazia M Marcoccia Francesca F Piccirilli Alessandra A Pellegrini Cristina C Colapietro Martina M Sabatini Alessia A Celenza Giuseppe G Kerff Frédéric F Amicosante Gianfranco G Galleni Moreno M Mercuri Paola Sandra PS
Antimicrobial agents and chemotherapy 20160422 5
Site-directed mutagenesis of CphA indicated that prolines in the P158-P172 loop are essential for the stability and the catalytic activity of subclass B2 metallo-β-lactamases against carbapenems. The sequential substitution of proline led to a decrease of the catalytic efficiency of the variant compared to the wild-type (WT) enzyme but also to a higher affinity for the binding of the second zinc ion. ...[more]
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