ParD Antitoxin Hotspot Alters a Disorder-to-Order Transition upon Binding to Its Cognate ParE Toxin, Lessening Its Interaction Affinity and Increasing Its Protease Degradation Kinetics.

ABSTRACT: Type-II toxin-antitoxin (TA) systems are comprised of two tightly interacting proteins, and operons encoding these systems have been identified throughout the genomes of bacteria. In contrast to secretion system effector-immunity pairs, TA systems must remain paired to protect the host cell from toxicity. Continual depletion of the antitoxin results in a shorter half-life than that of the toxin, though it is unclear if antitoxins can be effectively degraded when complexed with toxins. The current work probed the protein-protein interface of the PaParDE1 TA system, guided by an X-ray crystal structure, to determine contributions of antitoxin amino acids to interaction kinetics and affinity. These studies identified a "hotspot" position that alters the binding mode and resulting affinity (

SUBMITTER: Snead KJ 

PROVIDER: S-EPMC9805813 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature