Lysine 300 is essential for stability but not for electrogenic transport of the Escherichia coli NhaA Na⁺/H⁺ antiporter.

ABSTRACT: Na⁺/H⁺ antiporters are located in the cytoplasmic and intracellular membranes and play crucial roles in regulating intracellular pH, Na⁺, and volume. The NhaA antiporter of Escherichia coli is the best studied member of the Na⁺/H⁺ exchanger family and a model system for all related Na⁺/H⁺ exchangers, including eukaryotic representatives. Several amino acid residues are important for the transport activity of NhaA, including Lys-300, a residue that has recently been proposed to carry one of the two H⁺ ions that NhaA exchanges for one Na⁺ ion during one transport cycle. Here, we sought to characterize the effects of mutating Lys-300 of NhaA to amino acid residues containing side chains o

SUBMITTER: Calinescu O 

PROVIDER: S-EPMC5427271 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature