Profiling marine bacterial dioxygenase gene involved in Polycyclic Aromatic Hydrocarbon degradation

Abstract

Abstract. Mishra M, Das S. 2017. Profiling marine bacterial dioxygenase gene involved in Polycyclic Aromatic Hydrocarbon degradation. Ocean Life 1: 32-40. The degradation of polycyclic aromatic hydrocarbons (PAHs) by bacteria has been widely reported. While many pure cultures have been isolated and characterized for their ability to grow on PAHs, little is known regarding the diversity of microorganism involved in PAH degradation in the environment. The aim of this study was characterization of the gene for enzymes involve in PAHs Degradation, and to make a bank collection of strains for further screening research. Pure bacterial cultures were sampled from a highly enriched consortium for biodegradation analysis. Bacterial strains capable of degrading pyrene and anthracene were isolated from Paradeep estuary (Odisha, India) water sample by selective enrichment. Five strains of pyrene and anthracene degrading pure cultures were collected, named as MP-1, MP-4, MP-9, MP-14, MP-18. Isolates were characterized by gram staining, utilization of citrate, sugar fermentation, swimming and swarming motility and antibiotic sensitivity test. In seven days isolates MP-1,MP-4,MP-9,MP-14,MP-18 shown to degrade 58.4%, 42.1%, 29.1%, 31.7%, 31.8% of pyrene at a concentration 100 mg/l and 56.3%, 46%, 44.6%, 30.4%, 48.2% of anthracene at a concentration100mg/l. Polymerase chain reaction (PCR) with PAH-specific primers successfully amplifies a dioxygenase gene in MP-4. The presence of dioxygenase gene may lead to unraveling the underlying mechanism on how bacteria develop the abilities to degrade high-molecular-weight PAH. The understanding to profile not only the bacterial community but also the dioxygenases which they encode provides a powerful way for both assessing bioremediation potential in the environment and the discovery of novel dioxygenase genes.