Initial reactions involved in the bacterial degradation of polycyclic aromatic hydrocarbons (PAHs) include a ring-dihydroxylation catalyzed by a dioxygenase and a subsequent oxidation of the dihydrodiol products by a dehydrogenase. In this study, the dihydrodiol dehydrogenase from the PAH-degrading Sphingomonas strain CHY-1 has been characterized. The bphB gene encoding PAH dihydrodiol dehydrog...

The biochemistry of malignant melanoma is reviewed. The biosynthesis of melanin from tyrosine is described and the role of tyrosinase and other enzymes in melanoma considered. Detailed methods for the assay of free catechols, their metabolites and urinary indole melanogens are included. Normal values for these constituents and their significance in the evaluation of melanoma patients are discus...