Genomic Study Of Asgard Archaea In Mangrove Wetland In Zhanjiang Bay

As an important tropical and subtropical coastal ecosystem,mangroves have high productivity and support complex microbial communities and high microbial diversity.As an important part of microorganisms,archaea are widely distributed in the mangrove environment and have an important impact on the mangrove environment.The Asgard archaea superphylum is a large class of archaea newly discovered,with very rich diversity and high environmental abundance,as well as rich and diverse metabolic pathways.The study of Asgard archaea in mangroves helps to understand the role of archaea in wetland biogeochemical cycles,and provides important theoretical support for the protection of mangrove wetlands and the development of microbial resources.Since most archaea cannot be cultivated,the current knowledge about them is still very limited.The development of metagenomics technology enables scientists to obtain the genome of a single archaea without isolation and purification,and realize in-depth study of its ecological functions.In this paper,using metagenomic analysis technology,sediments were collected from the mangroves in Zhanjiang Bay for sequencing and analysis,and the genome of the microorganisms in the mangrove environment was restored.Analyze the genome of Asgard archaea,and conduct comparative genomics research in conjunction with public databases.The main research results are as follows:(1)Collect sediment samples of different depths in the mangroves of Zhanjiang Bay,and perform assembly and annotation of the samples.The results showed that the main microorganisms in the mangrove microbial community structure in Zhanjiang Bay were Proteobacteria,Chlorocurve,Firmicutes,Bacteroides,Planctomycetes,Actinomycotas,and Gastroarchaea.The main ecological functions of these microorganisms include degradation of proteins,amino acids and carbohydrates in the environment.They use these substances to produce energy or their own substances,and at the same time produce biologically active metabolites,such as toxins and drugs.16SrRNA analysis found that there are abundant Asgard archaea.(2)The Hermodarchaeota was found in the mangroves of Zhanjiang Bay.After the phylogenetic analysis,it was found that the archaea was a new archaeal phylum,belonging to the Asgard superphylum.Genome annotation results show that Hermodarchaeota genome contains alkyl/benzyl succinate synthase genes that degrade alkanes and aromatic hydrocarbons in the environment.Then connect the complete benzoic acid metabolism and ?-oxidation pathway for further degradation.Finally,the WLP pathway is coupled with the denitrification function of nitrate reductase to achieve the function of degrading alkanes and aromatic hydrocarbons in the environment.Transcriptome analysis shows that this pathway is active in the environment.(3)Download all high-quality mangrove Asgard archaeal genomes in the database and all Asgard archaeal genomes in Zhanjiang Bay,as well as all public metagenomic data in the database.These data are used to analyze the environmental function and distribution of Asgard archaea.As a result,it was found that the mangrove contains all the classifications of Asgard archaea,some of which are only found in the mangrove environment;These genomes participate in the carbon,nitrogen and sulfur cycles of mangroves through different metabolic pathways in the environment;Asgard archaea are widely distributed in mangroves and the abundance of Asgard archaea in tropical mangroves is higher.