Algae (Gongolaria barbata) was collected in two different locations in the Northern Adriatic Sea (Gulf of Trieste). DNA was isolated from different algal parts and the hypervariable V4 region (515F- 805R) of the bacterial 16S rRNA was amplified. Sequencing was performed on the Illumina Miseq v2 platform (2 × 250 bp pair-end).