View Abstract

A GENOMIC INFLECTION POINT IN THE TWILIGHT ZONE OF THE OCEAN’S INTERIOR (E)

Ocean surface versus deep-water microbial communities differ profoundly, yet the specific nature and scope of microbial evolutionary and ecological transitions into the ocean’s interior are not well understood. We assembled a catalogue of over 8.9 million non-redundant genes, from a 1.5-year time-series survey of station ALOHA microbial communities spanning the surface to 1000 m depth. Analyses of the station ALOHA gene catalogue revealed a sharp genomic “inflection point” directly below the euphotic zone, where the genomic and proteomic properties of the whole microbiome, as well as phylogenetically diverse individual clades, changed rapidly across a narrow depth horizon. Below this inflection point, the microbial community trended towards higher gene guanine-cytosine (G+C) content in lockstep with changing features of the surrounding physicochemical environment. Along with changing G+C content, shifts in genome codon usage and encoded proteome nitrogen and carbon composition were evident. Together, the data reflect a multispecies, community-wide shift in genome evolutionary modalities, which appear to be driven by differences in availability and regularity of energy and nutrients across the transition zone.

Authors

Bryant, J. A., Massachusetts Institute of Technology, USA, JBryant@mit.edu

Mende, D. R., University of Hawaii at Manoa, USA, danielrmende@gmail.com

Aylward, F. O., University of Hawaii at Manoa, USA, faylward@hawaii.edu

Eppley, J. M., University of Hawaii at Manoa, USA, jmeppley@hawaii.edu

Nielsen, T. N., Joint Genome Institute, USA, torben@lbl.gov

DeLong, E. F., University of Hawaii at Manoa, USA, edelong@hawaii.edu

Details

Oral presentation

Session #:040
Date: 03/01/2017
Time: 14:45
Location: 314

Presentation is given by student: Yes