Functional roles of Mg²⁺ binding sites in ion-dependent gating of a Mg²⁺ channel, MgtE, revealed by solution NMR.

ABSTRACT: Magnesium ions (Mg²⁺) are divalent cations essential for various cellular functions. Mg²⁺ homeostasis is maintained through Mg²⁺ channels such as MgtE, a prokaryotic Mg²⁺ channel whose gating is regulated by intracellular Mg²⁺ levels. Our previous crystal structure of MgtE in the Mg²⁺-bound, closed state revealed the existence of seven crystallographically-independent Mg²⁺-binding sites, Mg1-Mg7. The role of Mg²⁺-binding to each site in channel closure remains unknown. Here, we investigated Mg²⁺-dependent changes in the structure and dynamics of MgtE using nuclear magnetic resonance spectroscopy. Mg²⁺-titration experiments, using wild-type and mutant forms of MgtE, revealed that th

SUBMITTER: Maruyama T 

PROVIDER: S-EPMC5882242 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature