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.
The CFR is the official record of all regulations created by the federal government. It is divided into 50 volumes, called titles, each of which focuses on a particular area. Almost all environmental regulations appear in Title 40. The CFR is revised yearly, with one fourth of the volumes updated every three months.