THE MICROBIOLOGY OF COAL I

Abstract

Oxidation of phenanthrene by an organism isolated from garden soil, resembling Pseudomonas aeruginosa, was studied. When provided at a level of 1.0% in a mineral salts medium, 65-78% of the phenanthrene is decomposed after 72 hours of room temperature incubation. An intermediate product appearing between 36 and 48 hours of incubation was isolated and identified as 1-hydroxy-2-naphthoic acid. Manometric studies have shown that the organism possesses the enzymes necessary to oxidize salicylic acid and catechol, the oxidation past l-hydroxy-2-naphthoic acid proceeding via this known pathway. Some indications that an alternate pathway to 1,2-naphthoquinone may exist, were also found in manometric experiments. Oxidation of l-hydroxy-2-naphthoic acid by resting cells in the Warburg vessel consistently released 3.5 to 5.5[mu] moles of CO2. Amount of 1,2-naphthoquinone equivalent to the decarboxylation of 3.5 to 5.5[mu] moles of l-hydroxy-2-naphthoic acid inhibited not only endogenous respiration, but interfered with the oxidation of salicylic acid as well.