Structure and mechanism of oxalate transporter OxlT in an oxalate-degrading bacterium in the gut microbiota.

ABSTRACT: An oxalate-degrading bacterium in the gut microbiota absorbs food-derived oxalate to use this as a carbon and energy source, thereby reducing the risk of kidney stone formation in host animals. The bacterial oxalate transporter OxlT selectively uptakes oxalate from the gut to bacterial cells with a strict discrimination from other nutrient carboxylates. Here, we present crystal structures of oxalate-bound and ligand-free OxlT in two distinct conformations, occluded and outward-facing states. The ligand-binding pocket contains basic residues that form salt bridges with oxalate while preventing the conformational switch to the occluded state without an acidic substrate. The occluded pocket can accommodate oxalate but not larger dicarboxylates, such as metabolic intermediates. The permeation

SUBMITTER: Jaunet-Lahary T 

PROVIDER: S-EPMC10070484 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature