Microbial rhodopsins are major contributors to the solar energy captured in the sea
Gómez-Consarnau, L.; Raven, J.A.; Levine, N.M.; Cutter, L.S.; Wang, D.; Seegers, B.; Aristegui, J.; Fuhrman, J.A.; Gasol, J.M.; Sañudo-Wilhelmy, S.A. (2019). Microbial rhodopsins are major contributors to the solar energy captured in the sea. Science Advances 5(8): eaaw8855. https://dx.doi.org/10.1126/sciadv.aaw8855 In: Science Advances. AAAS: New York. e-ISSN 2375-2548, more | |
Authors | | Top | - Gómez-Consarnau, L.
- Raven, J.A.
- Levine, N.M.
- Cutter, L.S.
| - Wang, D.
- Seegers, B.
- Aristegui, J., more
| - Fuhrman, J.A.
- Gasol, J.M., more
- Sañudo-Wilhelmy, S.A.
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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. |
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