Metagenome of a Versatile Chemolithoautotroph from Expanding Oceanic Dead Zones
David A. Walsh,1
Elena Zaikova,1
Charles G. Howes,1
Young C. Song,1
Jody J. Wright,1
Susannah G. Tringe,2
Philippe D. Tortell,3,4
Steven J. Hallam1,5,*
Oxygen minimum zones, also known as oceanic "dead zones," are
widespread oceanographic features currently expanding because
of global warming. Although inhospitable to metazoan life, they
support a cryptic microbiota whose metabolic activities affect
nutrient and trace gas cycling within the global ocean. Here,
we report metagenomic analyses of a ubiquitous and abundant
but uncultivated oxygen minimum zone microbe (SUP05) related
to chemoautotrophic gill symbionts of deep-sea clams and mussels.
The SUP05 metagenome harbors a versatile repertoire of genes
mediating autotrophic carbon assimilation, sulfur oxidation,
and nitrate respiration responsive to a wide range of water-column
redox states. Our analysis provides a genomic foundation for
understanding the ecological and biogeochemical role of pelagic
SUP05 in oxygen-deficient oceanic waters and its potential sensitivity
to environmental changes.
2 Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA.
3 Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
4 Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
5 University of British Columbia Graduate Program in Bioinformatics, Vancouver, BC V6T 1Z4, Canada.
* To whom correspondence should be addressed. E-mail: shallam{at}interchange.ubc.ca
