Photosynthetic Characteristics and Carbonic Anhydrase Activity in Cells Cultured Photoautotrophically and Mixotrophically and Cells Isolated from Leaves

概要

論文の詳細を見る
Cultured green cells of Nicotiana tabacum var. Samsun, Cytisus scoparius Link and Hyosqyamus niger which were grown photoautotrophically under a stream of air enriched with 1 % CO_2 or mixotrophically in the presence of 3% sucrose and ordinary air showed very low carbonic anhydrase activity, which was only 0-9% of that in the respective intact leaves. The CO_2 compensation point for photosynthesis of autotrophically and mixotrophically cultured green cells of tobacco was higher than 0.3 mM NaHCO_3 at pH 7.8, but that of the cells isolated from tobacco leaves was lower than O. I mM NaHCO_3 at pH 7.8. The fact that the cultured cells cannot grow photoautotrophically under ordinary air is due to a high CO_2 compensation point in photosynthesis. The dark respiratory activity in both photoautotrophically and mixotrophically cultured tobacco cells was more than 7-fold that in the cells isolated from tobacco leaves. We therefore could not conclude whether the high CO_2 compensation point in the cultured cells is due to the low carbonic anhydrase activity or simply reflects the high respiratory activity.
日本植物生理学会の論文