Mutants of Escherichia coli that are resistant to certain beta-lactam compounds lack the ompF porin.
نویسندگان
چکیده
Carbenicillin-resistant mutants of Escherichia coli K-12 and B/r were found to produce greatly diminished levels of the porin coded by the ompF gene. Physiological and ecological implications of these findings are discussed.
منابع مشابه
Selection and characterization of beta-lactam-resistant Escherichia coli K-12 mutants.
beta-Lactam-resistant mutants of Escherichia coli K-12 were selected by using 12 different beta-lactam derivatives. The mutants fell into three categories showing (i) altered permeation through reduction or loss of outer membrane porin proteins (including ompF, ompR, and envZ alleles); (ii) increase in the rate of synthesis of chromosomally mediated beta-lactamase; or (iii) defective synthesis ...
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عنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 20 4 شماره
صفحات -
تاریخ انتشار 1981