Toward understanding the outer membrane uptake of small molecules by Pseudomonas aeruginosa.

ABSTRACT: Because small molecules enter Gram-negative bacteria via outer membrane (OM) channels, understanding OM transport is essential for the rational design of improved and new antibiotics. In the human pathogen Pseudomonas aeruginosa, most small molecules are taken up by outer membrane carboxylate channel (Occ) proteins, which can be divided into two distinct subfamilies, OccD and OccK. Here we characterize substrate transport mediated by Occ proteins belonging to both subfamilies. Based on the determination of the OccK2-glucuronate co-crystal structure, we identify the channel residues that are essential for substrate transport. We further show that the pore regions of the channels are rigid in the OccK subfamily and highly dynamic in the OccD subfamily. We also demonstrate that the substrate

SUBMITTER: Eren E 

PROVIDER: S-EPMC3636890 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature