Department of Agronomy, University of Illinois, Urbana, Illinois.
Plant Physiol. 1966 Jun;41(6):1004-13. doi: 10.1104/pp.41.6.1004.
The phosphate inhibition of succinate-powered contraction in corn mitochondria can be reversed with calcium. Associated with this reversal is an accumulation of phosphate and calcium. Both ions are essential for accumulation, although strontium will partially substitute for calcium. Arsenate does not substitute for phosphate except in producing the inhibition of contraction.The antibiotics oligomycin and aurovertin do not block the phosphate inhibition of contraction or the calcium-activated phosphate uptake associated with the release of the inhibition. Dinitrophenol uncouples the phosphate uptake but permits full contraction.Calcium promotes inorganic phosphate accumulation in root tissue as well as in mitochondria.The results are discussed from the viewpoint of theories of calcium reaction with high energy intermediates of oxidative phosphorylation. It is concluded that calcium probably reacts with X approximately P in corn mitochondria, rather than with X approximately I as with animal mitochondria.
钙可逆转磷酸盐对玉米线粒体中琥珀酸驱动收缩的抑制作用。与这种逆转相关的是磷酸盐和钙的积累。两种离子对积累都是必需的,尽管锶可以部分替代钙。砷酸盐不能替代磷酸盐,除非它会抑制收缩。抗生素寡霉素和金诺芬不会阻断磷酸盐对收缩的抑制作用,也不会阻断与抑制释放相关的钙激活磷酸盐摄取。二硝基苯酚使磷酸盐摄取解偶联,但允许完全收缩。钙促进根组织以及线粒体中无机磷酸盐的积累。从钙与氧化磷酸化高能中间产物反应的理论角度讨论了这些结果。结论是,钙可能与玉米线粒体中的 X 近似 P 反应,而不是与动物线粒体中的 X 近似 I 反应。