ID 1.14.13.18 DE 4-hydroxyphenylacetate 1-monooxygenase. AN 4-HPA 1-hydroxylase. AN 4-hydroxyphenylacetate 1-hydroxylase. AN 4-hydroxyphenylacetic 1-hydroxylase. CA (1) 4-hydroxyphenylacetate + H(+) + NADPH + O2 = H2O + homogentisate + CA NADP(+). CA (2) 4-hydroxyphenylacetate + H(+) + NADH + O2 = H2O + homogentisate + CA NAD(+). CC -!- Also acts on 4-hydroxyhydratropate forming 2-methylhomogentisate and CC on 4-hydroxyphenoxyacetate forming hydroquinone and glycolate. //