Small eukaryotic phytoplankton communities in tropical waters off Brazil are dominated by symbioses between Haptophyta and nitrogen-fixing cyanobacteria

Autor(es)

Ribeiro, Catherine Gerikas ^{[1, 2]} ; Lopes dos Santos, Adriana ^{[2, 3]} ; Marie, Dominique ^[2] ; Brandini, Frederico Pereira ^[1] ; Vaulot, Daniel ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Oceanog, Dept Oceanog Biol, Sao Paulo - Brazil

^[2] Sorbonne Univ, CNRS, UMR7144, Stn Biol Roscoff, Roscoff - France

^[3] Univ Mayor, GEMA Ctr Genom Ecol & Environm, Camino La Piramide 5750, Santiago - Chile

• Tipo de documento: Artigo Científico
• Fonte: ISME Journal; v. 12, n. 5, p. 1360-1374, MAY 2018.
• Citações Web of Science: 4

Resumo

Symbioses between eukaryotic algae and nitrogen-fixing cyanobacteria have been recognized in recent years as a key source of new nitrogen in the oceans. We investigated the composition of the small photosynthetic eukaryote communities associated with nitrogen-fixing cyanobacteria in the Brazilian South Atlantic Bight using a combination of flow cytometry sorting and high throughput sequencing of two genes: the V4 region of 18S rRNA and nifH. Two distinct eukaryotic communities were often encountered, one dominated by the Mamiellophyceae Bathycoccus and Ostreococcus, and one dominated by a prymnesiophyte known to live in symbiosis with the UCYN-A1 nitrogen-fixing cyanobacterium. Among nifH sequences, those from UCYN-A1 were most abundant but three other UCYN-A clades (A2, A3, A4) were also found. Network analysis confirmed the relation between A1 and A2 clades and their hypothesized hosts and pointed out to the potential association between novel Glade A4 with Braarudosphaera bigelowii, previously hypothesized to host A2. (AU)

• Processo FAPESP: 14/15242-2 - Abundância e diversidade de pico e nanofitoplâncton no sudoeste Atlântico ao largo da costa brasileira
• Beneficiário: Catherine Gérikas Ribeiro
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado
• Processo FAPESP: 12/04800-9 - Estrutura de comunidades diazotróficas na costa brasileira e zona oceânica adjacente
• Beneficiário: Catherine Gérikas Ribeiro
• Modalidade de apoio: Bolsas no Brasil - Doutorado