Allosteric effects of the coupling cation in melibiose transporter MelB.

ABSTRACT: The major facilitator superfamily (MFS) transporters play significant roles in human health and disease. Salmonella enterica serovar Typhimurium melibiose permease (MelB_St) catalyzes the symport of galactosides with Na⁺, H⁺, or Li⁺ and is a prototype of MFS transporters. We published the structures of MelB_St in both inward- and outward-facing conformations, bound to galactoside or Na⁺, and proposed that positive cooperativity of the co-transported solutes is crucial for the symport mechanism. Here, we elucidated the underlying mechanisms by analyzing MelB_St dynamics and the effects of melibiose, Na⁺, or both using hydrogen-deuterium exchange mass spectrometry (HDX-MS). We also refined the determi

SUBMITTER: Hariharan P 

PROVIDER: S-EPMC12851581 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature