Degradation of Pyrene by Mycobacterium aromativorans Strain JS19b1

Mycobacterium aromativorans JS19b1(T), isolated from a polycyclic aromatic hydrocarbon-contaminated soil, can grow with pyrene as a sole source of carbon and energy. A detailed pyrene metabolic map was constructed based on metabolite analysis by GC-MS and replacement cultures supplemented with the two intermediate metabolites phenanthrene-4,5-dicarboxylic acid and naphthalene-1,2-dicarboxylic acid. Strain JS19b1(I) can degrade pyrene through branched metabolic pathways, including its initial 4,5-dioxygenation and subsequent ortho- and metacleavages of 3,4-dihydroxyphenanthrene and naphthalene-1,2-diol. Dioxygenation of pyrene occurred on K-region to produce phenanthrene-4,5-dicarboxylic acid. 2,2'-Dicarboxy-6,6'-dihydroxybiphenyl and cis-3,4-dihydroxy-3,4-dihydrophenanthrene were also detected in phenanthrene4,5-dicarboxylic acid-supplemented replacement cultures, which suggests branching of pyrene catabolism to a typical pathway of 3,4-dihydroxyphenanthrene.