Two Trk/Ktr/HKT-type potassium transporters, TrkG and TrkH, perform distinct functions in Escherichia coli K-12.

ABSTRACT: Escherichia coli K-12 possesses two versions of Trk/Ktr/HKT-type potassium ion (K⁺) transporters, TrkG and TrkH. The current paradigm is that TrkG and TrkH have largely identical characteristics, and little information is available regarding their functional differences. Here, we show using cation uptake experiments with K⁺ transporter knockout mutants that TrkG and TrkH have distinct ion transport activities and physiological roles. K⁺-transport by TrkG required Na⁺, whereas TrkH-mediated K⁺ uptake was not affected by Na⁺. An aspartic acid located five residues away from a critical glycine in the third pore-forming region might be involved in regulation of Na⁺-dependent activation of TrkG. In addition, we found t

SUBMITTER: Tanudjaja E 

PROVIDER: S-EPMC9898762 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature