Open AccessIsolation and partial purification of a carbapenem‐hydrolysing metallo‐β‐lactamase from Pseudomonas cepacia
Author(s) -
Baxter Ian A.,
Lambert Peter A.
Publication year - 1994
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1994.tb07176.x
Subject(s) - cephaloridine , chemistry , carbenicillin , ceftazidime , imipenem , microbiology and biotechnology , meropenem , ethylenediaminetetraacetic acid , clavulanic acid , isoelectric point , isoelectric focusing , pseudomonas , chryseobacterium , enzyme , biochemistry , ampicillin , biology , chelation , bacteria , cephalosporin , pseudomonas aeruginosa , antibiotics , organic chemistry , amoxicillin , antibiotic resistance , genetics , 16s ribosomal rna , gene
A metallo‐β‐lactamase has been isolated from a clinical strain of Pseudomonas cepecia and partially purified using Cibacron blue F3GA coupled agarose. The resulting preparation showed a single band of β‐lactamase activity (p I 8.45) after analytical isoelectric focusing. The enzyme was particularly effective in the hydrolysis of imipenem. Meropenem, biapenem, cephaloridine, ceftazidine, benzylpenicillin, ampicillin and carbenicillin were also hydrolysed, although at a lower rate. An unusual inhibition profile was noted. Inhibition by the metal ion chelators ethylenediaminetetraacetic acid and o ‐phenanthroline was reversed by addition of zinc, indicating a metallo‐enzyme, whilst > 90% inhibition was attainable with 0.1 mM concentrations of tazobactam and clavulanic acid. A study of 8 other clinical isolates showed the enzyme to be present and inducible by imipenen in each case. This enzyme was assigned PCM‐I ( Pseudomonas cepacia metalloenzyme I).