Organismal and spatial partitioning of energy and macronutrient transformations within a hypersaline mat.
Phototrophic mat communities are model ecosystems for studying energy cycling and elemental transformations because complete biogeochemical cycles occur over millimeter-to-centimeter scales. Characterization of energy and nutrient capture within hypersaline phototrophic mats has focused on specific processes and organisms; however, little is known about community-wide distribution of and linkages between these processes. To investigate energy and macronutrient capture and flow through a structured community, the spatial and organismal distribution of metabolic functions within a compact hypersaline mat community from Hot Lake have been broadly elucidated through species-resolved metagenomics and geochemical, microbial diversity and metabolic gradient measurements. Draft reconstructed genomes of 34 abundant organisms revealed three dominant cyanobacterial populations differentially distributed across the top layers of the mat suggesting niche separation along light and oxygen gradients. Many organisms contained diverse functional profiles, allowing for metabolic response to changing conditions within the mat. Organisms with partial nitrogen and sulfur metabolisms were widespread indicating dependence on metabolite exchange. In addition, changes in community spatial structure were observed over the diel. These results indicate that organisms within the mat community have adapted to the temporally dynamic environmental gradients in this hypersaline mat through metabolic flexibility and fluid syntrophic interactions, including shifts in spatial arrangements.
Biological Science Division, Earth and Environmental Science Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
Jennifer M
JM
Mobberley
Whistler Center for Carbohydrate Research, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA.|Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA.
Stephen R
SR
Lindemann
Biological Science Division, Earth and Environmental Science Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.|The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164, USA.
Hans C
HC
Bernstein
Chemical and Biological Signature Sciences, National Security Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
James J
JJ
Moran
Biological Science Division, Earth and Environmental Science Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.|The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164, USA.
Ryan S
RS
Renslow
The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164, USA.
Jerome
J
Babauta
Environmental Molecular Sciences Laboratory, Earth and Environmental Science Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
Dehong
D
Hu
The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164, USA.
Haluk
H
Beyenal
Biological Science Division, Earth and Environmental Science Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
William C
WC
Nelson
D001669:Biochemical Phenomena; D000458:Cyanobacteria / Q000378:metabolism / Q000502:physiology*; D017753:Ecosystem; D056186:Metagenomics; D010100:Oxygen / Q000378:metabolism; D054712:Salinity
D010100:Oxygen
element transformations; hypersaline; magnesium sulfate; metagenomics; phototrophic; reconstructed genomes