First Molecular Identification of Symbiotic Archaea in a Sponge Collected from the Persian Gulf, Iran.

Background: Marine sponges are associated with numerically vast and phylogenetically diverse microbial communities at different geographical locations. However, little is known about the archaeal diversity of sponges in the Persian Gulf. The present study was aimed to identify the symbiotic archaea with a sponge species gathered from the Persian Gulf, Iran.

Methods: Sponge sample was collected from a depth of 3 m offshore Bushehr, Persian Gulf, Iran. Metagenomic DNA was extracted using a hexadecyl trimethyl ammonium bromide (CTAB) method. The COI mtDNA marker was used for molecular taxonomy identification of sponge sample. Also, symbiotic archaea were identified using the culture-independent analysis of the gene and PCR- cloning.

Results: In this study, analysis of multilocus DNA marker and morphological characteristics revealed that the sponge species belonged to isolate PG_BU4. PCR cloning and sequencing showed that all of the sequences of archaeal gene libraries clustered into the uncultured archaeal group.

Conclusion: The present study is the first report of the presence of the genus of in the Persian Gulf. Traditional taxonomy methods, when used along with molecular techniques, could play a significant role in the accurate taxonomy of sponges. Also, the uncultured archaea may promise a potential source for bioactive compounds. Further functional studies are needed to explore the role of the sponge-associated uncultured archaea as a part of the marine symbiosis.