they include the specific systems a ( accepting l-arginine and l-lysine ) , b ( l-phenylalanine , l-tyrosine ) , c ( l-glutamic acid ) and d ( l-leucine ) , system i ( a 'general amino-acid permease ' ) and the low-affinity systems ii and iii , which accept acidic or basic amino acids , respectively , but also l-phenylalanine .
C0003765
arginine
C0301714
basic amino acids