Preliminary Study On Functional Gene And Secondary Metabolites Of Two Halophilic Actinomycetes YIM 96633 And YIM 96077

As major source of natural bioactive activity products,actinomycetes play an important role in agriculture.industry,medicial and environmental protection.There are two problems in isolation of bioactive natural products from actinomycetes:drug-resistant bacteria,tumor and repetitive isolation of known compounds,therefor the resarch target in the field has tranfered to extreme environmental actinomycetes.halophilic actinomycetes which live in hypersaline habitat is a kind of extreme environmental actinomycetes.Compared with abundant research results in bioactive natural products from marine halophilic actinomycetes,the study on terrigenous halophilic actinomycetes is poor.Through long-term research people has accumulated abundant terrigenous halophilic actinomycetes which shows a variety of functional gene and great potential for production of bioactive secondary metabolites.17 halophilic anctinomycetes used in this study are isolated from salt lake in Xinjiang.Using little fermentation with different broth mediums and extracting fermentation liquor to obtain crude extract,combined with TLC chemical diversity and multiple antibacterial activity expriment,Saccharomonospora YIM 96633 which inhibits multiple pathogenic bacteria was selected.The best method of fermentation was determined by screening fermentation conditions of selected strain by multiple drug-resistant Escherichia coli antibacterial activity experiment.After enlarge fermentation of total amount 120L,many isolations and purification methods was used to obtained compounds,10 compounds was purified finally.Besed on 1H-NMR and 13C-NMR data of 10 compounds,the structure of 10 compounds were identified,including3-Ethylindole and 3-indolecarboxylic acid,2-(Diethylamino)etc.In addition,the study includes gene mining of a potential novel family strain YIM 96633.0n the bases of the evidence of polyphasictaxonomy experiments,a novel family is proposed.Whole genome sequencing of YIM 96077 offers folloing information:the genome of strain YIM 96077 is 5092472 bp long with 66.632%average GC content,which is predicted covering a total of 4865 genes.1661 protein-coding genes are distributed into GOC functional categories and 187 metabolic pathway are annotated by querying KEGG database.Through querying antismash databse,YIM 96077 possesses 5 biosynthesis gene clusters and 4 of them have low similarity with known gene clusters that code several metabolites with anti-cancer,anti-bacterial and antitumor acivity.The result shows that the genes of YIM 96077 may code secondary metabolites with new structure.The study indicates that terrigenous halophilic actinomycetes YIM 96633 and YIM 96077 own potential for production of bioactive secondary metabolites.However,the problem that gene expression is not stable is a hard nut to crack.The study provide a method that combined antibacterial activity expriment and gene mining which lay root for developing halophilic actinomycetes resource.