title: Permeability of the outer membrane of Moraxella catarrhalis for beta-lactam antibiotics.
abstract: The susceptibility of ten clinical isolates and a standard reference strain, ATCC25238, of Moraxella catarrhalis to 22 beta-lactam antibiotics was examined and compared with that of Escherichia coli strain B. All the strains of M. catarrhalis tested, especially the non beta-lactamase-producing strain ATCC25238, were more susceptible to a rang of structurally unrelated beta-lactam antibiotics, including small Mr carbapenems, than E. coli B. The permeability of the M. catarrhalis outer membrane to beta-lactam antibiotics was examined by the swelling technique with proteoliposomes reconstituted from outer membranes. The diffusion rate of beta-lactams through the liposome membrane was inversely related to their Mr, a relationship which might be expected for entry by diffusion through a porin.
authors.affiliation: Department of Microbiology, Kyoto Pharmaceutical University, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Gotoh
authors.forename: S
authors.initials: S
authors.lastname: Tanaka
authors.forename: T
authors.initials: T
authors.lastname: Nishino
mesh_terms: D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability; D004058:Diffusion; D007700:Kinetics; D008081:Liposomes / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D001936:Moraxella catarrhalis / Q000378:metabolism* / Q000648:ultrastructure; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D008081:Liposomes; D047090:beta-Lactams