Open AccessIsolation and preliminary characterization of β‐lactamase excretory mutants of Escherichia coli K‐12
Author(s) -
FogniniLefebvre Nicole,
Portalier Raymond
Publication year - 1984
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.1574-6968.1984.tb00330.x
Subject(s) - escherichia coli , plasmid , pbr322 , mutant , microbiology and biotechnology , enterobacteriaceae , isolation (microbiology) , extracellular , biology , chemistry , biochemistry , dna , gene
Escherichia coli exc mutants able to release the plasmid pBR322‐encoded β‐lactamase (EC 3.5.2.6) into the extracellular medium have been isolated using a new in situ plate assay. A preliminary characterization of the exc mutants was carried out: the presence of exc mutations was associated with a specific or pleiotropic pattern of excretion of periplasmic enzymes, an increased sensitivity to different growth inhibitors (EDTA, chloramphenicol, cholic acid) and a poor growth on various carbon sources. After quantitative analysis, three groups of exc mutants were identified on the basis of their temperature‐dependent or ‐independent pattern of growth and β‐lactamase synthesis and excretion.