Journal Article
Proceedings of the National Academy of Sciences, vol. 111, iss. 31, pp. 11395-11400, 2014
Authors
Alyse K. Hawley, Heather M. Brewer, Angela D. Norbeck, Ljiljana Paša-Tolić, Steven J. Hallam
Abstract
Significance
Oxygen is an important organizing principle in marine ecosystems. As oxygen levels decline, energy is increasingly diverted away from higher trophic levels into microbial community metabolism causing changes in carbon and nutrient cycling. Here we use metagenomic and metaproteomic methods to chart in situ metabolic networks linking key microbial players driving carbon and nutrient cycling in a seasonally stratified fjord, Saanich Inlet, a model ecosystem for studying microbial responses to changing levels of water column oxygen deficiency. Based on this evidence, we develop a conceptual model that describes coupling of chemotrophic energy production with dark carbon fixation along defined redox gradients with implications for primary production and possibly carbon sedimentation in expanding marine oxygen minimum zones.
