Coordination in phenanthrene biodegradation: Pyruvate as microbial demarcation

The principle involved in the phenanthrene degradation is regarded as the key to unlock the mechanisms governing the pathway of other polycyclic aromatic hydrocarbons. Past studies have made some pathway proposals via metabolite analysis. In this study, two dominating species (phn01 and phn02) were isolated from oil contaminated soil and were used in lab-scale experiment of phenanthrene degradation. The GC/MS results revealed the metabolites of pyruvate, phthalate, 1-hydroxy-2-naphthaldehyde and 9-phenanthrol at retention time of 12.01, 15.34, 16.82 and 18.16 min, respectively. A new proposal of pathway was derived. Selective degradation indicated the relationship of coordination between these two species, one of which was mainly responsible for pyruvate production and the other for pyruvate consumption. Pyruvate played a role of microbial demarcation which might be closely associated with invoking signal for microbial community during biodegradation.