The Effects Of Rubisco And Rubisco Activase On Photosynthesis In Wheat

In this article, Rubisco and Rubisco activase were purified from wheat leaves. The antibody of Rubisco and Rubisco activase were prepared. Photosynthetic rate, the activities and contents of Rubisco and Rubisco activase were traced during diurnal change. The effects of environmental condition to photosynthetic rate and Rubisco, Rubisco activase were studied. The results were abstracted as followings:1. Rubisco was separated, purified from wheat leaves by ammonium sulfate precipitation, gel filtration, ion-exchange chromatography on the basis of Rubisco characteristic, such as dissolvability, molecular size and shape, electric charge. The purified Rubisco showed only one band by ND-PAGE and two predominant bands by SDS-PAGE. One was the large subunit, whose molecular weight was about 55 000. The other was the small subunit, whose molecular was about 14 800.2. Rubisco activase was separated, purified from wheat leaves and showed two predominant band at 41 000, 45 000 by SDS-PAGE.3. Rubisco and Rubisco activase activity were determined and studied by 14C-marking method and ATP is essential to stabilize Rubisco activase activity during purification and storage.4. Injected rabbit with purified Rubisco and Rubisco activase to prepare polyclonal antiserum, The titer of Rubisco was 64 by agar diffusion . Elisa liter of Rubisco was 10 000, and that of Rubisco activase was 1 600.5. ELISA was used to measure Rubisco and Rubisco activase content in this paper.6. The diurnal changes of photosynthesis were studied, the initial activities of Rubisco is showed a linearly significant correlation with photosynthetic rate. The diurnal changes of photosynthetic rate and initial activities of Rubisco appeared as acurve with a peak at noon in the mild, bright day and two peaks with a midday depression in the hot day with dry wind. Rubisco activity is regulated by Rubisco activase in vivo.7. After studying the changes of photosynthetic rate, the activities and contents of Rubisco, Rubisco activase with Varies environmental conditions(such as light, H2O; temperature; CO2, nitrogen fertilizer, and source-sink limitation etc.), We enclosed that environmental conditions effect photosynthetic rate by change the activities of Rubisco and stomatic conductance.