南海南部陆坡表层沉积物细菌和古菌多样性

Bacterial and archaeal diversity in surface sediment from the south slope of the South China Sea

从南海南部陆坡表层沉积物中扩增了细菌和古菌16S rDNA序列,并对克隆子文库进行系统发育分析。细菌序列以变形杆菌(Proteobacteria)居多,其次是浮霉菌(Planctomycete)、酸杆菌(Acidobacteria)和candidate division OP10,另外还有少量铁还原杆菌(Deferrobacteres)、candidate di-vision OP3、OP11、OP8、TM6、疣微菌(Verrucomicrobia)和螺旋体(Spirochaetes)。古菌序列分别来自泉古生菌(Crenarchaeota)和广古生菌(Euryarchaeota),以Marine Benthic Group B(MBGB)、Marine Crenarchaeotic GroupⅠ(MGⅠ)、Marine Benthic Group D(MBGD)和South African Gold Mine Eu-ryarchaeotic Group(SAGMEG)为主。少量序列为C3、甲烷杆菌(Methanobacteriales)和Novel Eu-ryarchaeotic Group(NEG)。结果表明海底表层沉积物中有丰富多样的微生物群落。

Diversity of bacteria and archaea was studied in deep marine sediments by PCR amplification and sequence analysis of 16S rDNA. Sample analysed was from IMAGES（International Marine Past Global Change Study） 147 at site of the south slope of the South China Sea. DNA was amplified from samples at the surface layer of core MD05-2896. Phylogenetic analysis of clone libraries showed a wide variety of uncultured bacteria and archeae. The most abundant bacterial sequences （phylotypes） corresponded to the Proteobacteria, followed by the Planctomycete, Acidobacteria and candi- date division OP10. Phylotypes ascribing to Deferrobacteres, Verrucomicrobia, Spirochaetes and candidate division clades of OP3, OPll, OP8 and TM6 were also identified. Archaeal 16S rDNA sequences were within phylums of Crenarchaeota and Euryarchaeota, respectively. The majority of archaeal phylotypes were Marine Benthic Group B（MBGB）, Marine Crenarchaeotic Group Ⅰ （MG Ⅰ ）, Marine Benthic Group D（MBGD） and South African Gold Mine Euryarchaeotic Group（SAGMEG）. Additional sequences grouped with the C3, Methanobacteriales and Novel Euryarchaeotic Group （NEG）. These results indicate that bacteria and archaea are abundant and diversified in surface environment of subseafloor sediments.