Rubisco Activity Is Related To Photosystem I In Leaves
Rubisco content and its in vivo activity (kcat), as well as PSI content were measured in leaves of sunflower, tobacco, potato and birch. The biological variation of k cat was wide, ranging from 1 to 6 s−1 at 22.5°C. Plotting kcat against (Rubisco sites/PSI) resulted in a reciprocally decreasing relationship. The data show that carbamylated Rubisco sites have variable average catalytic turnover rates in planta, regulated by Rubisco Activase in cooperation with a PSI-related factor.
KeywordsLeaves Rubisco Rubisco activase photosystem I
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