Intradiol pathway of para-cresol conversion by Rhodococcus opacus 1CP

The growth of Rhodococcus opacus 1CP in medium with different concentrations of p-cresol as the sole source of carbon and energy was studied. It was shown that the optimal concentration of p-cresol was 600 mg/L. The ability of this strain to transform practically all amounts of p-cresol to 4-methylcatechol followed by its utilization through ortho-pathway was shown. New enzymes (4-methylcatechol 1,2-dioxygenase, catechol 1,2-dioxygenase, and methylmuconate cycloisomerase) were purified to homogeneity and characterized. Based on the data obtained on p-cresol degradation, formation of intermediates, and the enzymes participating in this pathway, we suggest an ortho-pathway of p-cresol degradation by R. opacus 1CP through 4-methylcatechol and 3-methyl-cis, cis-muconate.