Biodegradation of polycyclic aromatic hydrocarbons

The pathway for the microbial degradation of simple polycyclic aromatic compounds viz. naphthalene, anthracene, phenanthrene and substituted naphthalenes are described. Emphasis has been given to the diversity of metabolic reactions for the degradation of naphthalene in bacterial, fungal, algal and mammalian systems. A brief account of the genetics of naphthalene catabolic plasmids with special reference to the plasmid NAH7 has been given. This is followed by a brief discussion of our present knowledge of the metabolism of phenanthrene, anthracene, methylnaphthalenes and naphthoic acids.