GENERIC DIFFERENCE OF SPONGE-ASSOCIATED BACTERIAL ISOLATES FROM TROPICAL AND TEMPERATE OCEAN

Abstract

GENERIC DIFFERENCE OF SPONGE-ASSOCIATED BACTERIAL ISOLATES FROM TROPICAL AND TEMPERATE OCEANSung-Hyun Yang, Kae Kyoung Kwon, Seung-Seob Bae, Hee-Soon Lee, Jung-Hyun Lee, and Sang-Jin KimMarine Biotechnology Research Center, Korea Ocean Research & Development Institute, Ansan 425-600, Korea, e-mail: s-jkim@kordi.re.krSponge-associated microorganisms have been highlighted due to their possibility of producing novel bioactive products. In the present study a variety of sponge-associated bacterial strains was isolated from tropical ocean, Chuuk Island, Micronesia, and temperate ocean, Taejongdae, Korea, to screen useful compounds. Compositional difference of those isolates from two areas was compared based on the 16S rRNA gene sequences. Majority of isolates from temperate area affiliated as members of the alpha-proteobacteria and was distributed into various genera including the genus Pseudovibrio of the family Rhodobacteraceae and several genera of the family Erythrobacteraceae. However, most isolates from tropical area affiliated only into the genus Pseudovibrio and they produce a different clade separately from the temperate isolates even in the same genus. Isolates belonging to the gamma-proteobacteria from temperate area mostly affiliated into the genera Bowmanella, Pseudoalteromonas, Shewanella and Vibrio, however, those from tropical area into the genera Acinetobacter, Halomonas, Microbulbifer and Pseudomonas. In case of Bacteroidetes, isolates also clearly discriminated as Flavobacteria from temperate area or Sphingobacteria from tropical area. It is unclear, however, whether the generic difference of sponge-associated isolates between tropical and temperate ocean observed in this study could be occurred due to different temperature or differences of environmental condition and/or sponge species. [Supported by Marin-Bio 21 Program & KORDI]