Holotoxin disassembly by protein disulfide isomerase is less efficient for Escherichia coli heat-labile enterotoxin than cholera toxin.

ABSTRACT: Cholera toxin (CT) and Escherichia coli heat-labile enterotoxin (LT) are structurally similar AB₅-type protein toxins. They move from the cell surface to the endoplasmic reticulum where the A1 catalytic subunit is separated from its holotoxin by protein disulfide isomerase (PDI), thus allowing the dissociated A1 subunit to enter the cytosol for a toxic effect. Despite similar mechanisms of toxicity, CT is more potent than LT. The difference has been attributed to a more stable domain assembly for CT as compared to LT, but this explanation has not been directly tested and is arguable as toxin disassembly is an indispensable step in the cellular action of these toxins. We show here that PDI disassembles CT more efficiently than LT, which provides a possible explanation for the gre

SUBMITTER: Serrano A 

PROVIDER: S-EPMC8741891 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature