Mutation of two key aspartate residues alters stoichiometry of the NhaB Na⁺/H⁺ exchanger from Klebsiella pneumoniae.

ABSTRACT: Bacterial NhaB Na⁺/H⁺ exchangers belonging to the Ion Transporter superfamily are poorly characterized in contrast to Na⁺/H⁺ exchangers of the Cation Proton Antiporter superfamily which have NhaA from Escherichia coli as a prominent member. For a more detailed understanding of the intricacies of the exchanger's transport mechanism, mutational studies are essential. Therefore, we mutated two protonatable residues present in the putative transmembrane region of NhaB from Klebsiella pneumoniae (KpNhaB), which could serve as substrate binding sites, Asp146 and Asp404, to either glutamate or alanine and analyzed transport function and stability of the mutants using electrophysiological and fluorimetric techniques. While mutation of either Asp residue

SUBMITTER: Patino-Ruiz M 

PROVIDER: S-EPMC6817889 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature