동해, 일본해구의 심해 퇴적물내 고세균류 다양성 분석

Abstract

Archaeal community structures in deep-sea sediments has been compared from three stations (one from Japan Trench; station K-1, 6,300 m depth and two from East Sea (Japan Sea); station #485 and O-3, 3,145 and 3,300 m depth respectively) which were geographically localized in western and eastern part of the Japanese Islands. Archaeal community was analyzed by T-RFLP (terminal-restriction fragment length polymorphism) analysis based on 16S rRNA genes. Also, cloning and sequencing of archaeal 16S rDNAs were carried out for the characterization of each terminal restriction fragments (T-RFs). In the T-RFLP analysis, despite their geographical difference, the archaeal community of K-1 and #485 were very similar with one major T-RF peak with 327 and 263 bases in length by tetrameric restriction enzyme HhaI and RsaI, respectively. But, the archaeal community of O-3 contains additional three T-RFs as well as the major peak of K-1 and #485. Eighty five archaeal 16S rDNA clones were obtained and subjected on RFLP analysis. The twelve different RFLP types were obatained and each representative clone for the sites was sequenced. Phylogenetic analysis of the 16S rDNA sequences showed that most clones were clustered within Marine group I which specified the major peak at the site K-1 and #485. But 48% and 32 % of O-3 clones were affiliated into marine benthic group B of Crenarchaeota and anaerobic methane-oxidizing archaeal group-2 of Euryarchaeota, respectively which indicated that the sediment of the O-3 site was different from the other sediments. This study showed that the combination of T-RFLP analysis and cloning and sequencing of 16S rDNA could be used for the rapid comparison and identification of archaeal components of natural environments.