Characterization of the active-site residues asparagine 167 and lysine 161 of the IMP-1 metallo beta-lactamase.
FEMS Microbiol Lett
; 197(1): 85-9, 2001 Apr 01.
Article
in En
| MEDLINE
| ID: mdl-11287151
ABSTRACT
The roles of lysine at position 161 and asparagine at position 167 in IMP-1 metallo beta-lactamase were studied by site-directed mutagenesis. These residues are highly conserved in metallo beta-lactamases and are thought to be present in the active-site cavity. Mutant enzymes with alanine or aspartic acid at position 167 showed almost the same properties as the wild-type enzyme. Kinetic parameters for the mutant enzymes differing at position 161 indicated that the positive charge of lysine 161 is required for electrostatic interaction with the carboxyl moiety of the substrate, i.e. C-3 of penicillins or C-4 of cephalosporins.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Asparagine
/
Beta-Lactamases
/
Lysine
Limits:
Humans
Language:
En
Journal:
FEMS Microbiol Lett
Year:
2001
Document type:
Article
Affiliation country:
Japón