The Ammonium Transporter (Amt) Family (TC 2.A.49) All functionally characterized members of the Amt family are ammonia or ammonium uptake transporters. Some, but not others, also transport methylammonium. The mechanism of energy coupling, if any, to methyl-NH2 or NH3 uptake by the AmtB protein of E. coli is not entirely clear. NH4+ uniport driven by the pmf, energy independent NH3 facilitation, and NH4+/K+ antiport have been proposed as possible transport mechanisms. In Corynebacterium glutamicum and Arabidopsis thaliana, uptake via the Amt1 homologues of AmtB has been reported to be driven by the pmf. [Transport and binding proteins, Cations and iron carrying compounds]
Jiyao W et al.(2023). "The conserved domain database in 2023.",