Metagenomics of the Amazon
Metagenomics of the water column in the pristine upper course of the Amazon River
We describe high throughput sequencing results from a sample from the largest river in the world, the Amazon. This is also the first study of a pristine tract of a large river, and the largest dataset so far for any freshwater habitat as well. . The sample was collected at a site nearly 400km upstream from Manaus, Brazil at the end of the dry season (September, average rainfall for the month 50 mm) and was taken from mid stream and mid waters (8 m depth with the bottom at 15 m). Total DNA from a single representative sample from the mid water column was directly 454 pyrosequenced providing 375 Mbp of sequence data.
River water is a small percentage of the total freshwater on Earth but represents an essential resource for mankind. Microbes in rivers provide essential ecosystem services including the mineralization of significant quantities of organic matter originating from terrestrial habitats. The Amazon river in particular is famous for its immense size and importance in the mobilization of both water and carbon out of its enormous basin. Here we present the first metagenomic study on the microbiota of this enormous river. It presents many features in common with the other freshwater metagenome available (Lake Gatun in Panama) and much less similarity with marine samples.