Conversion of 5CVA into vanillate by LigW in the presence of D2O. Mass spectra of vanillate produced in the presence of 0, 48, and 96% D2O are shown in panels A, B, and C, respectively. The deduced reaction pathway of LigW is illustrated in panel D on the basis of the result shown in this figure and that reported for vanillate decarboxylase of Rhodotorula rubra (11).