Permease involved in lysine uptake. H(+)(out) + L-lysine(out) = H(+)(in) + L-lysine(in) Deletion of the gene abolishes high-affinity lysine uptake without affecting growth on free amino acids. Belongs to the amino acid-polyamine-organocation (APC) superfamily. Amino acid transporter (AAT) (TC 2.A.3.1) family.