Research On The Thermophilic Resources Of Anshan Hot Spring And Analysis Of Microbial Diversity In Deep-sea Sediments

In this study, A total of 29 culturable thermophilic strains, which have been mainly divided into two genus Anoxybacillus and Geobacillus according to the phylogenetic analysis of the 16S rDNA sequences, have been isolated from Anshan hot spring. Seven of them are classed into Meiothermus and Thermus. These results suggest that thermophilic bacilli are predominant in the environment with moderate high temperature. The thermophiles in the hotspring mainly produce lipase and amylase, and produce xylanase partly.The environmental total DNA was directly extracted from four sediments in Pacific polymetallic nodule province (EP2005-04 and ES0505), East Pacific Rise (EPRTG5) and Southwest Indian Ridge (SWIR-TVG3). Four bacterial and two archaeal 16S rRNA gene libraries of were generated. Phylogenetic analysis indicated that clones of four bacterial libraries can be divided into 15 phylotypes: Alpha proteobacteria, Gamma proteobacteria, Delta proteobacteria), Beta proteobacteria, Planctomycetes, Cytophaga-Flavobacterium-Bacteroidetes(CFB), Acidobacteria, Verrucomicrobia, Chlorobi Nitrospira, Actinobacteria(High G+C G~+), Chloroflex, Firmicutes(Low G+C G~+), Deinococcus-Thermus and candidate division OP11. Excepting the sediment from EPRTG5, 16S rDNA sequences from members of Gamma proteobacteria dominated other three sediments samples, and it is revealed a high richness in these sediments bacterial communities. Two archaeal libraries (EPRTG5 and SWIR-TVG3) were within phylums of Crenarchaeota and Euryarchaeota. The majority of archaeal phylotypes was Marine Group I . LIBSHUFF statistics of 16S rDNA gene sequences from different libraries revealed major differences, indicating and considerable variability in bacterial community composition among regions.A moderate thermophilic, anaerobic bacterium, designated Z341, was isolated from a deep-sea hydrothermal vent sediment sample collected from the East Pacific Rise. The cells were straight and Gram-positive. The strain Z341 had 98% sequence similarity with Coloranaerobacter azorensis which was isolated from deep-sea hydrothermal vent on the Mid-Atlantic Rigde.