title: Resistance to a new catecholic cephem, BO-1341, in Pseudomonas aeruginosa PAO.
abstract: Two distinct types of mutant resistant to the catecholic cephem BO-1341 were isolated spontaneously from Pseudomonas aeruginosa PAO2146: (i) a mutant (CCB5-type) which produced beta-lactamase constitutively, and which appeared to result from a mutation in the regulatory gene (blaI at 41 min) controlling the structural gene (blaP at 25 min); (ii) a mutant (CCB7-type) with specific resistance to BO-1341. Induction of beta-lactamase production in strain CCB7 by BO-1341 was diminished markedly when compared with that in the parent strain. This was not the case for ceftazidime or cefoxitin, suggesting impaired uptake of BO-1341 as an explanation for the resistance. Electrophoretic analysis demonstrated increased production of a 55 kDa protein in the periplasmic space and a 84 kDa outer membrane protein. These data suggested that specific resistance to BO-1341 might involve quantitative alterations in the composition of the outer membrane and periplasmic proteins.
authors.affiliation: Okazaki Research Laboratories, Banyu Pharmaceutical Co. Ltd, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hazumi
authors.forename: K
authors.initials: K
authors.lastname: Matsuda
authors.forename: M
authors.initials: M
authors.lastname: Sanada
authors.forename: N
authors.initials: N
authors.lastname: Ohtake
authors.forename: N
authors.initials: N
authors.lastname: Tanaka
mesh_terms: D002440:Cefoxitin / Q000494:pharmacology; D002442:Ceftazidime / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology*; D002712:Chlorides; D004352:Drug Resistance, Microbial / Q000235:genetics; D004790:Enzyme Induction; D005290:Ferric Compounds / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D001618:beta-Lactamases / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D002511:Cephalosporins; D002712:Chlorides; D005290:Ferric Compounds; C058373:BO 1341; D002440:Cefoxitin; D002442:Ceftazidime; D001618:beta-Lactamases; C024555:ferric chloride