Isolation and diversity analysis of heterotrophic bacteria associated with sea anemones

A study was undertaken to investigate the heterotrophic bacterial flora associated with the seaanemones. Samples of the sea anemones Anthopleura midori were collected from the coast of Wei-hai and bacteria were isolated from these samples. Additionally, high numbers of viable bacteriawere obtained from the celom wall and surface of anemone, the community of cultivable bacteriawas very diverse. As a result of this isolation, 60 strains were obtained, 56 of them were selectedfor identification and characterization by 16S rRNA gene sequence analysis and limited pheno-typic testing. Among these isolates, 16 strains were phylogenetically related to members of thegenus Pseudoalteromonas and neighboring taxa. Other isolates included members of the generaColwellia, Vibrio, Acinetobacter, Pseudomonas, Endozoicomonas, Roseovarius, Paracoccus, Lok-tanella, Leisingera, Sulfitobacter, Bacillus, Staphylococcus, Plantibacter, Microbacterium, Micro-coccus, Joostella, Psychroserpens, Cellulophaga, Krokinobacter, Polaribacter and Psychrobacter.Seven potential novel species were found. Among 60 strains, 17 of them can produce proteolyticexoenzyme, 20 can produce lipolytic exoenzyme. Strain NQ8 has strong antagonistic effects onsome Vibrio strains. This study demonstrates that the culturable fraction of bacteria from the seaanemones Anthopleura midori is diverse and appears to possess much potential as a source for thediscovery of novel bioactive materials.