Pyrene metabolism and enzymes involved in Novosphingobium pentaromativorans US6-1

Abstract

Pyrene is a polycyclic aromatic hydrocarbon (PAH) commonly present in PAH-contaminated sites. Novosphingobium pentaromativorans US6-1 was isolated from sediment of Ulsan bay and has broad substrates with two to five rings PAHs. Newly and increased expression of proteins were found with 1-D PAGE or 2-DE and LC-MS/MS. Presence of pyrene 1,2-monoxygenase, pyrene 4,5-monoxygenase and 4,5-dihydroxypyrene dioxygenase indicates that degradation of pyrene in N. pentaromativorans US6-1 proceeds via multiple metabolic routes initiated by mono-(C-1,2 and C-4,5) and dioxygenation (C-4,5) reactions. Further degradation entered phenanthrene metabolic pathway and via either o-phthalate pathway or salicylate pathway, both pathways were subsequently entered tricarboxylic acid (TCA) cycle and mineralized to CO2. A pyrene degradation pathway for N. pentaromativorans US6-1 was proposed by identifying the enzymes involved in the pyrene degradation.