Microbial Taxonomic Study Of Two Novel Species Andqilian Mountain Permafrost Drilling DK8-19 Microbial Communities Analysis

This research focuses on the microbial taxonomic study of two novel species,through genetic and phylogenetic analysis to determine the germline attribution and select appropriate reference strains,combined with reference strains for physiological and biochemical characteristics,chemical taxonomic indicators,According to the measurement results of various taxonomic indicators,the taxonomic status was established and formally proposed as new species.The Real-time PCR and high-throughput sequencing methods were used to analyze the microbial biomass and community composition of DK8-19 in the frozen soil area of Qilian Mountains,and the relationship between the formation and transformation of natural gas hydrates and microbial activities was preliminarily explored.The strain DK6-66T was isolated from the subsurface sandstone sediment of the Qilian Mountain frozen soil area,which was Gram-negative,strictly aerobically grown,non-motile,and non-spore-forming.The most recent known strain is Hywienobacter arcticus KAC1l6881T.16S rDNA similarity is 98.2%,strain DK6-66T has a genome G+C mol%content of 60.4 mol%,growth optimum pH of 7,and optimum temperature of 22?.The main respiratory paralysis is MK-7.The main polar lipids were phosphatidylethanolamine(PE),two unidentified glycolipids,four unidentified aminolipids,two unidentified ammonia phospholipids and five unidentified polar lipids.The main fatty acids are summed feature 3(C16:1?7c/C16:1?6c)(26.8%),summed feature 4(anteiso-C17:1 B/iso-C17:1 I)(23.9%),iso-C15:O(18.7%),anteiso-C15:0(16.3%)and C16:1?5c(5.3%).In summary,the strain DK6-66T was proposed as a new species of the genus Hymenobacter,named Hymenobacter bucti sp.nov,and the model strain was DK6-66T(=CGMCC 1.15795T=KCTC 52629T).The strain G168T is isolated from the Chishui River in section of Maotai town.It is a new species of microorganism belonging to the genus Brevibacillus.It is Gram-positive,strictly aerobically grown,non-motile,produces elliptical endospores,and the colony is creamy and round.,smooth depression,where in the optimum growth temperature is 28?,the optimum pH is 8.The genomic G+C mol%of strain G168T was 52.7 mol%,and the similar strain with the highest similarity to 16SrDNA was 97.8%.The similarity of Brevibacillus panacihuwLi DCY35T was 97.8%.The chemically taxonomic study showed that the main polar lipid in the cell was phosphatidylethanolamine(PE),phosphatidylglycerol(PG),three unidentified polar lipids and four unidentified aminolipids,the main respiratory sputum is MK-7,the main fatty acid is iso-C15:0(18.9%),and Summed features 3(C16:1?7c/C16:1?6c)(17.2%),C16:0(16.7%),Summed features 1(C15:1 iso H/C13:0 3OH)(12.7%)and anteiso-C15:0(12.0%).In summary,strain G168T was proposed as a new species,and the strain named Brevibacillus buctense model was G168T(=CGMCC 1.15916T=KCTC 33863 T).Realtime-PCR assay showed that the microbial biomass of bacteria in DK8-19 borehole fluctuated with depth.High-throughput sequencing showed that the Methanobrevibacter genus was dominant in the archaeal community,and a small amount of Methanocorpusculum was found,which may be related to the production and transformation of natural gas hydrate.