Bacterial Synergy Analysis Of Lignin Deragdation Consortium At 30?

Natural lignin is difficult to be degraded because of its complex structure.It is not fully understood that the mechanism of synergistic degradation of lignin by microorganisms.In order to clarify the changes of bacterial community structure of the consortium at different stages of degradation,and the synergistic effect of lignin degradation was explored.Based on the test of degradation characteristics,total DNA of the consortium in original bacteria solution,initial stage,peak stage and final stage of degradation were selected for high-throughput sequencing of amplicons of bacterial 16 S r RNA genes.Meanwhile,and total RNA of the consortium in initial stage and peak stage of degradation were selected for high-throughput sequencing of macrotranscriptome.The aim of this study was to elucidate the synergistic degradation of the bacterial consortium from the perspective of DNA and RNA,and to reveal the contribution of bacterial in the process of lignin degradation.Based on the diversity of microbial annotated by 16 S r RNA genes,the mainly dominant genera were Pseudomonas(28.24%),Ruminofilibacter(26.87%),Sphaerochaeta(19.47%),Caenispirillum(7.97%)and Mangroviflexus(2.52%)at original bacteria solution.At initial stage of degradation,Pseudomonas(22.08%),Thauera(5.38%),Pannonibacter(6.60%),Anaerocolumna(6.47%),Sphaerochaeta(5.57%),Caenispirillum(5.52%),and Proteiniphilum(4.68%)were mainly dominant genera.At the peak stage of degradation,the mainly dominant genera were Anaerocolumna(44.78%),Pseudomonas(20.93%),Sphaerochaeta(5.57%),Caenispirillum(5.52%),Ruminofilibacter(4.10%),Paenibacillus(3.81%),Thauera(3.65%).However,the mainly dominant genera were Ruminofilibacter(22.76%),Sphaerochaeta(17.29%),Pseudomonas(12.55%),Caenispirillum(8.95%),Mangroviflexus(7.49%),Azospirillum(6.50%)and Thauera(2.19%)at the final stage of degradation.Based on the results from macrotranscriptome annotation,the transcripts information of consortium were mainly derived from the Clostridium(21.62%-49.35%),Lachnoclostridium(17.11%-19.40%),Cellulosilyticum(3.96%-10.84%),Thermoanaerobacterium(1.08%-7.99%),Herbinix(3.17%-3.76%),Bacillus(2.89%-3.34%)and Proteiniphilum(1.00%-3.41%).Based on gene annotated method by 16 S r RNA genes and macrotranscriptome method,there were 28 common bacteria.However,the microbial species were more abundant based on macrotranscriptomemethod.Using the four functional databases of proteins to analyze functional and metabolic characteristics of consortium,it was found that function concentrate on the carbohydrates metabolism and amino acid metabolism,which indicate consortium contained a large number of carbohydrate related enzyme genes and functional microorganisms.Using the CAZy database to annotate lignocellulase gene of consortium,it was found that 6AAs family genes to encoding the lignin degraded enzyme,and 7 GHs family genes and 2 CEs family genes to encoded the cellulose degrading enzyme,and 12 GHs family genes and 4 CEs family genes to encoded the hemicellulose degrading enzyme,and 34 GHs family genes to encoded the oligosaccharide degrading enzyme,and 37 CBMs family genes to encoded the auxiliary degradation.Meanwhile,the total of 27 Bacteria had been found to encode these enzyme genes.It was speculated that the degradation of lignin was achieved by the phenolic oxidation pathway of the depolymerized lignin bodies and the non-phenolic oxidation pathway of the degradation of small molecule compounds,and the hydrolysis of hemicellulose heteropolysaccharides.In this study,the the microbial community structure,function and metabolic characteristics changed significantly at different degradation stages in the process of lignin degradation.The genes related to carbohydrate metabolism were actively transcribed in consortium.Finally,According to the obtained functional enzyme gene of lignin degradation and functional microorganism of the consortium,synergistic effect degradation model of lignin in the consortium was constructed,and the mechanism of efficient degradation of lignin was revealed,so as to provide theoretical guidance and data support for the efficient degradation mechanism of lignin by the bacterial composite bacteria.