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TCIDNameDomainKingdom/PhylumProtein(s)
2.A.34.1.1









NhaB Na+:H+ antiporter of 513 aas and 11 or 12 TMSs.  NhaB is physiologically important when the level of NhaA activity is growth limiting, when nhaA is not sufficiently induced, and/or when NhaA is not activated (Pinner et al. 1993). The  stoichiometry of NhaB is 3H+/2Na+, different from that of NhaA (Pinner et al. 1994). It is required for intracellular pH regulation under alkaline conditions (Shimamoto et al. 1994). Mutations D146A/D404A in the Klebsiella pneumoniae ortholog changed the stoichiometry to a H+:Na+ ratio of < 1 (Patiño-Ruiz et al. 2019).

Bacteria
Proteobacteria
NhaB of E. coli (P0AFA7)
2.A.34.1.2









NhaB Na+,K+:H+ antiporter (Radchenko et al., 2006)
Bacteria
Proteobacteria
NhaB of Vibrio parahaemolyticus (BAC60335)
2.A.34.1.3









Na+/H+ antiporter that extrudes sodium in exchange for external protons, NhaB of 500 aas. Can also extrude lithium in exchange for protons.   Km values for Li+ and Na+ of 2.0 mM and 1.3 mM, respectively. The antiport activity was inhibited by amiloride with a Ki value of 0.04 mM (Kuroda et al. 2004).

Bacteria
Proteobacteria
NhaB of Pseudomonas aeruginosa