In order to get inside the cell, these molecules must pass through porins, which are protein channels that span the outer membrane. Antimicrobial resistance mechanisms in Pseudomonas aeruginosa Gram-negative bacteria possess proteins called porins in their outer membranes that, when altered, reduce or halt drug absorption.
The Code of Federal Regulations (CFR) is a codification (arrangement of) the general and permanent rules published in the Federal Register by the executive departments and agencies of the Federal Government. e-CFR Updated Daily; Beta Site.
Title 40, Code of Federal Regulations (40 CFR) Regulations are codified annually in the U.S. Code of Federal Regulations (CFR). Title 40: Protection of Environment is the section of the CFR that deals with EPA's mission of protecting human health and the environment. The CFR is available from FDSys.