Metagenomic Analysis of Cyanobacteria in an Oligotrophic Tropical Estuary, South Atlantic

Frontiers in Microbiology

Janaina Rigonato¹  José M. de Castro Nunes³  Helen M. de Jesus Affe³  Mariângela Menezes⁴ 

[1] CEA, Centre de Sequençage Genoscope, Institut de Biologie François Jacob, Evry, France;Centro de Energia Nuclear e Agricultura, Universidade de São Paulo, Piracicaba, Brazil;Laboratório de Algas Marinhas, Instituto de Biologia, Universidade Federal da Bahia, Salvador, Brazil;Laboratório de Ficologia, Departamento de Botânica, Museu Nacional, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil;

关键词: marine cyanobacteria;    metagenomic diversity;    functional profile;    shotgun;    Camamu Bay;   

DOI  :  10.3389/fmicb.2018.01393

来源: DOAJ

【 摘 要 】

This study assessed the species composition, distribution, and functional profiles of cyanobacteria in Camamu Bay, a tropical oligotrophic estuarine system on the northeast coast of Brazil, using shotgun metagenomic sequencing. Surface-water samples were evaluated in two different rainfall periods (rainy and dry seasons), at nine stations in the three hydrodynamic regions of the bay. At a fixed sampling station, on each season, samples were taken over a tidal cycle at 3-h intervals over 12 h. A total of 219 cyanobacterial taxa were identified, demonstrating a diverse community of freshwater, euryhaline, and marine cyanobacteria. The genera of greater relative abundance, Synechococcus and Prochlorococcus, corresponded to the picoplankton fraction. Although Camamu Bay has conspicuous marine characteristics, the contribution of freshwater during the rainy season caused variation in cyanobacteria community, with an increase in species richness. Due the high prevalence of Synechococcus (90% of the sequences), the functional analysis revealed only minor differences in gene content between the dry and rainy seasons. In both rainy and dry seasons, an increase in Prochlorococcus relative abundance occurred during high tide, demonstrating the tidal influence in the bay. The environmental characteristics of the bay provide niche conditions for a wide variety of cyanobacteria, including freshwater, euryhaline, and marine strains.

【 授权许可】

Unknown