2024 Volume 5
Volume 5 of the Asian Youth Journal of Biology.
Original Article
Preliminary Investigation on the Nature of Bacteria Associated with the Giant Barrel Sponge, Xestospongia testudinaria, Using Culture-Dependent Methods
by Yu Mun Chan, Lik Tong Tan, and Beverly Pi Lee Goh
Asian Youth Journal of Biology 2024, 5:1-16 [PDF of article]
Abstract. Within the Singapore marine environment, the diversity of bacterial communities in sponges is largely underexplored. This study in a preliminary investigation, using culture-dependent methods, on the bacterial community associated with the giant barrel sponge, Xestospongia testudinaria, from three locations, namely Pulau Hantu, P. Kusu and P. Semakau. Of the 84 marine microbial colonies isolated in this study, the phylogenetic analysis of 20 bacterial strains was successfully carried out. These bacterial isolates belonged to either phylum Proteobacteria or Firmicutes. Marine bacteria of the genera Bacillus and Vibrio were found in sponge samples from all three locations, while other bacteria genera, such as Labrenzia and Pseudoalteromonas, were only successfully isolated from samples from P. Hantu and Halomonas, Marinobacter, Pseudomonas and Phaeobacter detected from P. Samakau derived samples. In addition, two marine bacterial strains, S1B11 and S2A10, showed sequence identity of below 80% with their nearest relative of Labrenzia alba and Bacillus vietnamensis, respectively and could represent novel bacteria species. Majority of the isolated bacterial strains was found clustered in high sequence identity with bacterial species known to produce bioactive specialized metabolites, suggesting that these associated microbes could provide chemical defense for the host sponge and contribute to its resilience in Singapore waters.