FIG. 6.
Pathway proposed for the degradation of 4-t-butoxyphenol by an ipso-substitution mechanism in Sphingobium xenophagum Bayram. Growth experiments with 18O-labeled oxygen and water show that the ether oxygen in the alkoxyphenol was fully retained in the t-butanol metabolite. AH2 and A, an unidentified pair of reduced and oxidized cosubstrates, respectively.