N-terminal domain of 2,3-dihydroxy-p-cumate-3,4-dioxygenase (PpCmtC)
This subfamily contains the N-terminal, non-catalytic, domain of PpCmtC. 2,3-dihydroxy-p-cumate-3,4-dioxygenase (CmtC of Pseudomonas putida F1) is a dioxygenase involved in the eight-step catabolism pathway of p-cymene. CmtC acts upon the reaction intermediate 2,3-dihydroxy-p-cumate, yielding 2-hydroxy-3-carboxy-6-oxo-7-methylocta-2,4-dienoate. The CmtC belongs to the type I family of extradiol dioxygenases. Fe2+ was suggested as a cofactor, same as other enzymes in the family. The type I family of extradiol dioxygenases contains two structurally homologous barrel-shaped domains at the N- and C-terminal. The active-site metal is located in the C-terminal barrel and plays an essential role in the catalytic mechanism.