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Expanding knowledge of the R ubisco kinetics variability in plant species: environmental and evolutionary trends
Author(s) -
GALMÉS JERONI,
KAPRALOV MAXIM V.,
ANDRALOJC P. JOHN,
CONESA MIQUEL À.,
KEYS ALFRED J.,
PARRY MARTIN A. J.,
FLEXAS JAUME
Publication year - 2014
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/pce.12335
Subject(s) - phylogenetic tree , rubisco , crassulacean acid metabolism , biology , photosynthesis , kinetics , carboxylation , adaptation (eye) , botany , amino acid , biochemistry , gene , physics , catalysis , quantum mechanics , neuroscience
The present study characterizes the kinetic properties of ribulose‐1,5‐bisphosphate carboxylase/oxygenase ( R ubisco) from 28 terrestrial plant species, representing different phylogenetic lineages, environmental adaptations and photosynthetic mechanisms. Our findings confirm that past atmospheric CO 2 / O 2 ratio changes and present environmental pressures have influenced R ubisco kinetics. One evolutionary adaptation to a decreasing atmospheric CO 2 / O 2 ratio has been an increase in the affinity of R ubisco for CO 2 ( K c falling), and a consequent decrease in the velocity of carboxylation ( k cat c ), which in turn has been ameliorated by an increase in the proportion of leaf protein accounted by R ubisco. The trade‐off between K c and k cat c was not universal among the species studied and deviations from this relationship occur in extant forms of R ubisco. In species adapted to particular environments, including carnivorous plants, crassulacean acid metabolism species and C 3 plants from aquatic and arid habitats, R ubisco has evolved towards increased efficiency, as demonstrated by a higher k cat c / K c ratio. This variability in kinetics was related to the amino acid sequence of the R ubisco large subunit. Phylogenetic analysis identified 13 residues under positive selection during evolution towards specific R ubisco kinetic parameters. This crucial information provides candidate amino acid replacements, which could be implemented to optimize crop photosynthesis under a range of environmental conditions.