Peculiarities Of Metabolism Of Anthracene And Pyrene By Pycnoporus Sanguineus H1

Polycyclic aromatic hydrocarbons are a group of organic compounds with two or more fused benzene rings and have been identified as one of the most widely distributed pollutants. Plenty of studies were focused on microorganism degradation of PAHs and the most widely studied is white rot fungi. In our study, use ITS sequence test and named the 44# white rot fungi strain as Pycnoporus sanguineus H1. Then analysis this fungi’s characteristics of lignin-degrading enzymes, while ues anthracene and pyrene as model PAHs to study degradation rate, metabolism and metabolic pathways of Pycnoporus sanguineus H1. This study aimed at in-depth understanding of white rot fungi on the metabolism of PAHs and do some foundation for father theoretical studies.The results are showed as follow:1.Get the mycelium of the 44# white rot fungi from shake flask culture,then use DNA extraction kit to get fungi’s genome and obtain ITS fragments by PCR and identify it as Pycnoporus sanguineus by comparion of NCBI database. Through the experiment discovered that the lignin-degrading enzymes secreted by fungi can be detected in the laccase activity and can’t detect lignin peroxidase and manganese peroxidase activity. The activity of laccase is up to 5.36 U/mL in the twelfth day, after adding 2 g/L bran laccase activity achieved 15.60 U/mL, the optimum pH is about 4.5. Determination the molecular weight of laccase by SDS-PAGE is 43.2 KDa.2.Add 50 ppm anthracene and pyrene as sole carbon source in the medium, found that Pycnoporus sanguineus H1 could use anthracene as sole carbon source for growth in two weeks of shake-flask culture and pyrene is not available. After adding glucose and bran for co-metabolism, the degradation rate of anthracene and pyrene are significantly increased. The degrading rate of anthracene is 71.3% and pyrene is 30.2%. Detect by GC-MS, the main degradation product of anthracene is 9,10 anthraquinone and the possible catabolites of pyrene are 4,5-dihydropyrene and 4,5-dimethylphenanthrene.3.Using shake-flask to cultivate Pycnoporus sanguineus H1, then obtain the extracellular enzyme solution containing laccase and intracellular fraction containing cytochrome P450 by centrifugation. Add extracellular and intracellular fraction in the reaction system containing anthracene and pyrene. Then detect the residual of anthracene and pyrene by HPLC. Discovery the degradation of anthracene is mainly by extracellular laccase and the degradation of pyrene probably by intracellular fraction(the cytochrome P450). Adding inhibitors of laccase and cytochrome P450 and results demonstrate the preceding conclusions. Overall, the degradation of anthracene and pyrene not performed by a single enzyme or one step of reaction, but by the cooperation of extracellular and intracellular fraction.