Phylogeny of culturable cyanobacteria from Brazilian mangroves.
The cyanobacterial community from Brazilian mangrove ecosystems was examined using a culture-dependent method. Fifty cyanobacterial strains were isolated from soil, water and periphytic samples collected from Cardoso Island and Bertioga mangroves using specific cyanobacterial culture media. Unicellular, homocytous and heterocytous morphotypes were recovered, representing five orders, seven families and eight genera (Synechococcus, Cyanobium, Cyanobacterium, Chlorogloea, Leptolyngbya, Phormidium, Nostoc and Microchaete). All of these novel mangrove strains had their 16S rRNA gene sequenced and BLAST analysis revealed sequence identities ranging from 92.5 to 99.7% when they were compared with other strains available in GenBank. The results showed a high variability of the 16S rRNA gene sequences among the genotypes that was not associated with the morphologies observed. Phylogenetic analyses showed several branches formed exclusively by some of these novel 16S rRNA gene sequences. BLAST and phylogeny analyses allowed for the identification of Nodosilinea and Oxynema strains, genera already known to exhibit poor morphological diacritic traits. In addition, several Nostoc and Leptolyngbya morphotypes of the mangrove strains may represent new generic entities, as they were distantly affiliated with true genera clades. The presence of non-ribosomal peptide synthetase, polyketide synthase, microcystin and saxitoxin genes were detected in 20.5%, 100%, 37.5% and 33.3%, respectively, of the 44 tested isolates. A total of 134 organic extracts obtained from 44 strains were tested against microorganisms, and 26% of the extracts showed some antimicrobial activity. This is the first polyphasic study of cultured cyanobacteria from Brazilian mangrove ecosystems using morphological, genetic and biological approaches.
University of São Paulo, Center for Nuclear Energy in Agriculture, Laboratory of Molecular Ecology of Cyanobacteria, 13400-970 Piracicaba, São Paulo, Brazil.
Caroline Souza Pamplona
CS
Silva
University of São Paulo, Center for Nuclear Energy in Agriculture, Laboratory of Molecular Ecology of Cyanobacteria, 13400-970 Piracicaba, São Paulo, Brazil.
Diego Bonaldo
DB
Genuário
University of São Paulo, Center for Nuclear Energy in Agriculture, Laboratory of Molecular Ecology of Cyanobacteria, 13400-970 Piracicaba, São Paulo, Brazil.
Marcelo Gomes Marçal Vieira
MG
Vaz
University of São Paulo, Center for Nuclear Energy in Agriculture, Laboratory of Molecular Ecology of Cyanobacteria, 13400-970 Piracicaba, São Paulo, Brazil. Electronic address: fiore@cena.usp.br.
Marli Fátima
MF
Fiore
D001938:Brazil; D016000:Cluster Analysis; D000458:Cyanobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D053858:Metabolic Networks and Pathways / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D012988:Soil Microbiology; D014871:Water Microbiology
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S
16S rRNA gene sequencing; Atlantic Rain Forest; Brackish water; Marine cyanobacteria and bioactivity; Taxonomy