Abstract
All known phototrophic metabolisms on Earth rely on one of three categories of energy-converting pigments: chlorophyll-a (rarely -d), bacteriochlorophyll-a (rarely -b), and retinal, which is the chromophore in rhodopsins. While the significance of chlorophylls in solar energy capture has been studied for decades, the contribution of retinal-based phototrophy to this process remains largely unexplored. We report the first vertical distributions of the three energy-converting pigments measured along a contrasting nutrient gradient through the Mediterranean Sea and the Atlantic Ocean. The highest rhodopsin concentrations were observed above the deep chlorophyll-a maxima, and their geographical distribution tended to be inversely related to that of chlorophyll-a. We further show that proton-pumping proteorhodopsins potentially absorb as much light energy as chlorophyll-a–based phototrophy and that this energy is sufficient to sustain bacterial basal metabolism. This suggests that proteorhodopsins are a major energy-transducing mechanism to harvest solar energy in the surface ocean.
Document Type
Journal Article
ISSN
2375-2548
Volume
5
Issue
8
PubMed ID
31457093
School
Centre for Marine Ecosystem Research
RAS ID
30924
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Publisher
American Association for the Advancement of Science
Comments
Gómez-Consarnau, L., Raven, J. A., Levine, N. M., Cutter, L. S., Wang, D., Seegers, B., ... Sañudo-Wilhelmy, S. A. (2019). Microbial rhodopsins are major contributors to the solar energy captured in the sea. Science Advances, 5(8), Article eaaw8855. Available here