proton transmembrane transporter activity L-alanine transmembrane transporter activity L-alanine:proton antiporter activity GO:0140407 2019-12-11T14:17:48Z pg Enables the transfer of a solute or solutes from one side of a membrane to the other according to the reaction: H+(out) + L-alanine(in) = H+(in) + L-alanine(out). molecular_function amino acid:monoatomic cation antiporter activity