REDBIO México 2010

Folio: 10
Tipo de presentación: Oral
Tema: Metagenómica
Este trabajo se presentará en "Presentaciones Libres 14: Ómicas" el Miercoles dentro del horario 16:40 a 18:40

Metagenomics of the pristine upper course of the Amazon River (Solim›es), Brazil

Francisco Rodriguez-Valera, Rohit Ghai, Fernando Pellon de Miranda, Flavio Henrique-Silva
Universidad Miguel Hernandez, Alicante, España; 2- Universidade Federal de S‹o Carlos, Brasil; 3- CENPES-Petrobrás, Rio de Janeiro, Brasil

RESUMEN (ABSTRACT)
A large sequence dataset was generated by 454 pyrosequencing from prokaryotic biomass retrieved from the water column from the main course of the Rio Amazon about 400 Km upstream from Manaus. It is the first large screening of microbial biodiversity in the largest river on Earth still not largely impacted by pollution or human activities in general. The ca 400 Mbp of sequence provides a wealth of information about the microbes living in this iconic environment. Overall it was a mixture of low GC largely aquatic and high GC soil microbes. A large fraction of the bacterial reads could be assigned to single cell Actinobacteria with low GC content probably relatives of the luna group described by 16S rRNA sequencing from other freshwater bodies. Unexpectedly, the best recruiting genome seems to be a close relative to the marine archaeon Nitrosopumilus , an ammonia oxidizer isolated from a seawater fish tank. In addition freshwater relatives of Pelagibacter, Polynucleobacter and Acinetobacter had also close relatives in the sample. As expected in a dynamic water mass with very small light penetration, light related genes were nearly absent and the system was clearly heterotrophic, dominated by a wide diversity of genes involved in transport and degradation of organic matter. From this point of view the big river is like a huge waste treatment plant recycling the primary production of the equatorial rainforest. The only other large metagenome described from a fresh water environment, that of the still waters of lake Gatun in the panama canal is also tropical and shows the highest similarity to our own Amazon metagenome, indicating the low salinity variable as an important environmental factor. Financial support: PETROBRÁS, Brasil