Investigations To Pyrene Polluted Marine Sediments And The Mirobial Community Of PAHs Degrading Bacteria

Polycyclic aromatic hydrocarbons(PAHs)is a kind of typical persistent organic pollutants,with the main origin from human production activities.Its long half-life has led to serious environmental problem.The microorganism play key roles in the self purifying of PAHs in the marine sediments.Bohai Sea is the semi-closed sea located in the Northern China,and has been significantly polluted by the advanced Circum-Bohai Sea economic zone.So far,the research on the pollution and ecological state in Bohai Sea were mostly focus on the diversity and distribution of pollutions.Few studies were about the microbial communities and their response to the stress of PAHs pollutions.This study selected Bohai Bay as the exploring region to investigate the microbial communities structure,with applying Illumina Hiseq and 16 s r RNA mark gene.Furthermore,the sediments from this region was used to take part in enrichment culture.The high concentrations of pyrene was selected as the stress.Illumina Hiseq and 16 s r RNA mark gene were applied again to investigate the response of microbial communities to the stress.1.The following phylum were widely distrubted in the 22 sites: Proteobacteria,Acidobacteria,Chloroflexi,Bacteroidetes.The Gamma-Proteobacteria was the most abundant class.Piscirickettsiaceae related to fish diseases,Desulfobacteraceae and Rhodobacteraceae related to sulfur and carbon cycle,were abundant families.2.The grain size,depth,temperature,organic carbon,nitrite and nitrate shaped the microbial communities structure in sites.3.The microbial communities strcture has changed significantly before and after enrichment culture.Proteobacteria(86.19 %),Bacteroidetes(10.00 %),Acidobacteria,Chloroflexi and Planctomycetes were the most abundant phylum.Planctomyces,Flavobacterium and Bacillus performed rising tends while Desulfobacter performed descend tends in the culture.Vibrio,Pseudidiomarina,Marinobacter and Pseudoalteromonas increased first and then decreased.Most of those genera were reported to be capacity to degrade PAHs.