Name: Elizabeth Dinsdale

Email: elizabeth_dinsdale@hotmail.com

Author: Elizabeth Dinsdale, Alejandra Prieto Davo, Matthew Haynes, Katie Barrot, Tracey McDole, Ed Delong and Forest Rohwer

Author affiliation:

Abstract title: Viruses from an oxygen minimum zone off Iquique, Chile

Absstract:

Oxygen minimum zones are increasing worldwide and are hot beds of microbial and viral activity. The role of viruses in maintaining the low oxygen conditions is unknown. A permanent oxygen minimum zone exists offshore from Iquique, Chile and makes a perfect location to understand how these zones are established and maintained. The first sampling of this zone was conducted in June 2008, as part of the joint Agouron research expedition, which is a combined project collecting measurements on the microbes, viruses and water chemistry. The viral community was analyzed by direct counts, production assays and metagenomic analysis at 4 to 5 depths at inshore and offshore site. Preliminary results suggest that viral numbers were higher in the euphotic zone, lower within the oxygen minimum zone and increased again at 500m where oxygen levels increased again. Microbial numbers showed the opposite pattern. The analysis of the first viral metagenome from 200m showed that virus within the oxygen minimum zone had a high number of sequences that showed similarity to cell wall, DNA metabolism, and virulence associated activity. Many viral metagenomes from the marine environment have sequences similar to photosynthetic genes, but these were absent from this 200m sample, which is to be expected given that this sample is below the euphotic zone. Given that the oxygen minimum zone is high in nitrogen products the lack of sequences similar to nitrogen metabolism in this metagenome was surprising.