Molecular characterization of bacteria from sponge, Theonella sp

Abstract

Bacteria already known to have association with the sponges but their roles within the sponges still being unclear. Perhaps, the presence of uncultured bacteria within those sponges have made study by culture-dependent techniques are not suitable. Thus, this present study was focused mainly on identification of bacteria associated with the sponges using molecular approaches and investigation of total community of bacteria within those sponges obtained at Karah Island, Terengganu. Amplification of extracted DNA using RAPD-PCR and analysis of the 16S rDNA clones have been carried out to determine the type of bacteria strains in the sponge samples. As a result, RAPD profile generated the unique polymorphism produced by nine samples of sponge and a total of twenty colonies were obtained in the construction of 16S rDNA clones from sample F due to the low number of transformants during the shorter time of ligation reaction. Analysis of 16S rDNA clones retrieved from sample F that represented the sponge, Theonella sp. indicated that 100 % of uncultured bacteria. Three out of twenty colonies which were F2, F6 and F12 have been successfully extracted of its plasmid and sequenced. Result indicated that uncultured bacteria clone TK35 and uncultured cyanobacterium clone 106-2-1 with 94-98 % sequence similarity analyzed after BLAST. Results are in agreement with previous study that showed the abundances of the bacteria community including the uncultured bacteria within the sponges.