we conclude that the 14c-lysine fluxes are mediated by two systems , one , shared with phenylalanine , which is inhibited by proline , beta-alanine , and l-alanine , and one which is inhibited by l-alanine and phenylalanine but inaccessible to proline , beta-alanine , and meaib .
C0001898
l-alanine
C0000392
beta-alanine