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Size matters for single-cell C4 photosynthesis in Bienertia.

ABSTRACT: Bienertia cycloptera belongs to a diverse set of plants, recently discovered to perform C₄ photosynthesis within individual mesophyll cells. How these plants accomplish high photosynthetic efficiency without adopting Kranz anatomy remains unanswered. By modelling the processes of diffusion, capture, and release of carbon dioxide and oxygen inside a typical Bienertia mesophyll cell geometry, we show that a spatial separation as low as 10 ?m between the primary and the secondary carboxylases, can, on its own, provide enough diffusive resistance to sustain a viable C₄ pathway at 20 °C, with a CO₂ leakage <35%. This critical separation corresponds to a cell diameter of 50 ?m, consistent with the observed range where Bienertia's mesophyll cells start to develop their characteristic mature anatomy. Our results are robust to significant alterations in model assumptions and environmental conditions, their applicability extending even to aquatic plants.

SUBMITTER: Juric I

PROVIDER: S-EPMC5853773 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Size matters for single-cell C4 photosynthesis in Bienertia.

Jurić Ivan I González-Pérez Vinicio V Hibberd Julian M JM Edwards Gerald G Burroughs Nigel J NJ

Journal of experimental botany 20161012 2

Bienertia cycloptera belongs to a diverse set of plants, recently discovered to perform C<sub>4</sub> photosynthesis within individual mesophyll cells. How these plants accomplish high photosynthetic efficiency without adopting Kranz anatomy remains unanswered. By modelling the processes of diffusion, capture, and release of carbon dioxide and oxygen inside a typical Bienertia mesophyll cell geometry, we show that a spatial separation as low as 10 μm between the primary and the secondary carboxy ...[more]

PMID: 27733441

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