AME 79:259-272 (2017)  -  DOI: https://doi.org/10.3354/ame01830

ABSTRACT: Cyanobacteria are commonly associated with marine sponges and are known to be difficult to isolate. In the present study, we used isolation and molecular techniques to investigate the diversity of Cyanobacteria associated with the intertidal marine sponge host Hymeniacidon perlevis, collected along the coast of Portugal (Northeast Atlantic). Cyanobacterial community profiling and comparison using 16S rRNA gene-sequence-based denaturing gradient gel electrophoresis (DGGE) revealed different banding patterns between the sponge tissue and seawater. We succeeded in isolating Cyanobacteria belonging to the genera Synechococcus, Cyanobium, Synechocystis, Nodosilinea, Pseudanabaena and Phormidesmis from the sponge tissues. Chlorophyll a concentrations were very low, in spite of the diversity of cyanobacteria identified. DGGE analyses comparing sponge samples and ambient seawater further revealed the presence of Synechococcus, Acaryochloris and Prochlorococcus. Many of the isolated cyanobacteria show a high similarity with previously isolated free-living cyanobacteria from the coast of Portugal, highlighting the advantages of using sponges as a source for obtaining cyanobacteria present only in small amount in seawater.

KEY WORDS: Cyanobacteria · Marine sponges · Diversity · Phylogeny · DGGE · North-eastern Atlantic coast