Chorismate acid is branch point in aromatic amino acids biosynthesis , related to phenylalanine , bifunctional enzymes chorismate mutase / prephenate dehydratase ( encoded by phea ) is rate - limiting enzyme 分支酸是芳香族氨基酸合成途径的分支点,与苯丙氨酸合成有关,双功能酶分支酸变位酶-预苯酸脱水酶( phea基因编码)是关键酶。