Akademik Veri Yönetim Sistemi
13th International Conference on Toxic Cyanobacteria, Hania, Yunanistan, 4 - 08 Mayıs 2025, ss.217, (Özet Bildiri)
Cyanobacteria cell surface favorable for other organisms such as heterotrophic bacteria and nutrient exchanges occur between these microorganisms. Recent advances of next generation sequencing techniques enabled metagenomic analysis of microalgal-bacterial communities based on taxonomic profiling by amplicon sequencing. ln this study, we analyzed the composition of the bacterial community in three samples by nanopore sequencing: a cyanobacterial bloom sample of Planktothrix rubescens, two non-axenic culture of cyanobacteria including one toxic Microcystis aeruginosa and one taste and odour producer non-toxic Microcoleus sp. Using nanopore sequencing approach, we revealed a clear distinction at the species level. Pseudomonadota was abundant phyla in all samples (relative abundance was 12% in bloom, 11% in M. aeruginosa and 6% Microcoleus) followed by and Bacteroidota (2% in bloom, 0.6% in M. aeruginosa and 1.2% Microcoleus). Taste and odour producer Microcoleus cyanosphere showed 2 additional phylum Bacillota (2%) and Planctomycetota (0.2%). At the species level, abundant bacteria (>1%) were different in all samples suggesting a spesific association between microalgal-bacterial communities. In bloom sample, Curvibacter sp. AEP1-3 (2.3%), Rhodoferax sediminis (2%), R. saidenbachensis (1.4%) and Aquirufa nivalisilvae (1.4%) were abundant (>1%). ln Microcystis aeruginosa culture sample, Hydrogenophaga sp. NH-16 (4%), Porphyrobacter sp. LM 6 (2%) and Serpentinimonas maccroryi (1.7%) were abundant. ln Microcoleus sp. culture, Crinalium epipsammum (17%), Limnospira indica (2.4%), Sphingopyxis sp. EG6 (1.7%), Allocoleopsis franciscana (1.4%) and Clostridium estertheticum (1.3%) were abundant. Cyanobacteria associated bacteria could have important functions such as promoting cyanobacterial growth (Curvibacter, Rhodoferax etc.), colony formation of cyanobacteria (Porphyrobacter) and also cyanobacteria could have important functions for promoting bacterial growth producing substrates for them (Hydrogenophaga). Further studies are needed to understand the ecological functions of associated bacteria in toxic and taste-odour producer cyanobacteria cyanosphere. The present study has shown that the nanopore sequencing approach is able to assess the diversity of these associated bacteria.