Microbial rhodopsins on leaf surfaces of terrestrial plants.

Faculty of Biology, Lorry I Lokey Interdisciplinary Center for Life Sciences and Engineering, Faculty of Computer Science, Technion - Israel Institute of Technology, Haifa 32000, Israel.
Environmental Microbiology (Impact Factor: 6.24). 09/2011; 14(1):140-6. DOI: 10.1111/j.1462-2920.2011.02554.x
Source: PubMed

ABSTRACT The above-ground surfaces of terrestrial plants, the phyllosphere, comprise the main interface between the terrestrial biosphere and solar radiation. It is estimated to host up to 10(26) microbial cells that may intercept part of the photon flux impinging on the leaves. Based on 454-pyrosequencing-generated metagenome data, we report on the existence of diverse microbial rhodopsins in five distinct phyllospheres from tamarisk (Tamarix nilotica), soybean (Glycine max), Arabidopsis (Arabidopsis thaliana), clover (Trifolium repens) and rice (Oryza sativa). Our findings, for the first time describing microbial rhodopsins from non-aquatic habitats, point towards the potential coexistence of microbial rhodopsin-based phototrophy and plant chlorophyll-based photosynthesis, with the different pigments absorbing non-overlapping fractions of the light spectrum.

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