title: Outer membrane penetration by (2,3)-methylenepenams.
abstract: The penetration of the Escherichia coli outer membrane by two sterically restricted analogs of penicillin G was determined. The analog corresponding to the "open" conformation of penicillin G penetrated faster than the "closed"-form analog did, and both analogs penetrated faster than penicillin G did. The results suggest that the conformation of the beta-lactam nucleus may affect penetrability via the porin-mediated pathway.
authors.affiliation: Roche Research Center, Nutley, New Jersey 07110.
authors.forename: J S
authors.initials: JS
authors.lastname: Chapman
authors.forename: N H
authors.initials: NH
authors.lastname: Georgopapadakou
mesh_terms: D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism* / Q000648:ultrastructure; D007536:Isomerism; D007700:Kinetics; D010400:Penicillin G / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001425:Bacterial Outer Membrane Proteins; C054982:2,3-methylene penam; D001618:beta-Lactamases; D010400:Penicillin G