Summary of Abstract Submission

Abstract Submission No. IO50-09-0015PresentationPoster

QUANTITATIVE PROTEOMICS OF SINKING PARTICLES IN THE ARABIAN SEA

Richard Keil*1, Jaqui Neibauer1, Kelsey van der Elst1, Christina Biladeau1, Allan Devol1

1 University of Washington, USA

ABSTRACT :

Free-drifting sediment net traps were deployed between 80 and 500m for 1-3 days each during the late monsoon-intermonsoon transition in the central Arabian Sea (October 2007). Two locations (19.5 and 15.5N) were within the thick and permanently oxygen deficient zone, and a third (11N) had a much shallower and thinner oxygen minimum. Organic carbon fluxes ranged from 13.2 g m2 y-1 at 80 m to a minimum of 1.1 g m2 y-1 at 500 m. Fluxes at 11N attenuate slower than within the ODZ. Martin curve attenuation coefficients for 19.5N and 15.5N are 0.59 and 0.63 and for 11N it is 0.98. Meta and targeted proteomic approaches were used to assess and quantify proteins in the sinking particles. 1000+ proteins were identified on average, with the majority being from autotrophs and aerobic heterotrophs. Proteins derived from chemoautotroph organisms constitute a minor component of the quantified proteins. Proteins in the sinking particles for denitrification dominated over those for anammox by a 5:1 ratio.