Phenol 2-monooxygenase (phenol hydroxylase) is a flavoprotein monooxygenase, able to use molecular oxygen as a substrate in the microbial degredation of phenol. This protein is encoded by a single gene and uses a tightly bound FAD cofactor in the NAD(P)H dependent conversion of phenol and O2 to catechol and H2O. This group is related to the NAD binding ferredoxin reductases.