Anaplerotic flux into the Calvin-Benson cycle: hydrogen isotope evidence for in vivo occurrence in C₃ metabolism.

ABSTRACT: As the central carbon uptake pathway in photosynthetic cells, the Calvin-Benson cycle is among the most important biochemical cycles for life on Earth. A carbon flux of anaplerotic origin (i.e. through the chloroplast-localized oxidative branch of the pentose phosphate pathway) into the Calvin-Benson cycle was proposed recently. Here, we measured intramolecular deuterium abundances in leaf starch of Helianthus annuus grown at varying ambient CO₂ concentrations, C_a . Additionally, we modelled deuterium fractionations expected for the anaplerotic pathway and compared modelled with measured fractionations. We report deuterium fractionation signals at H¹ and H² of starch glucose. Below a C_a change point, these signals increase with decreas

SUBMITTER: Wieloch T 

PROVIDER: S-EPMC9305100 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature