Wilson R H, Minton G A
The Department of Botany, The University of Texas, Austin, Texas 78712, USA.
Biochim Biophys Acta. 1974 Jan 18;333(1):22-7. doi: 10.1016/0005-2728(74)90158-3.
(1) The transport of Ba2+ by mung bean (Phaseolus aureus L) mitochondria is examined and its uptake properties compared with the accumulation of other alkaline earth metals by plant mitochondria. Uptake is supported by oxidizable substrates but not by ATP under the conditions examined. Ba2+ uptake shows an absolute requirement for Pi, whereas AsO4, acetate and oxalate do not replace Pi. ATP synthesis inhibits Ba2+ uptake 50% and both 2,4-dinitrophenol and valinomycin plus K+ inhibit uptake over 80%. (2) The relative capacity to transport a series of alkaline earth metals showed a preferred order of: Sr2+ > Ca2+ > Ba2+ >> Mg2+. Mitochondria isolated from three plant sources showed net levels of Mg2+ uptake 7% or less than the observed Sr2+ uptake values. The same relative order of alkaline earth metal supported uptake of Pi was observed with bean (Phaseolus vulgaris L) mitochondria. It is suggested that salt transport in plant mitochondria involves a carrier complex which binds both divalent cations and Pi.
(1) 研究了绿豆（Phaseolus aureus L）线粒体对Ba2+的转运，并将其摄取特性与植物线粒体对其他碱土金属的积累进行了比较。在所研究的条件下，摄取由可氧化底物支持，但不由ATP支持。Ba2+摄取绝对需要Pi，而AsO4、乙酸盐和草酸盐不能替代Pi。ATP合成抑制Ba2+摄取50%，2,4-二硝基苯酚和缬氨霉素加K+均抑制摄取超过80%。(2) 转运一系列碱土金属的相对能力显示出以下优先顺序：Sr2+ > Ca2+ > Ba2+ >> Mg2+。从三种植物来源分离的线粒体显示，Mg2+摄取的净水平比观察到的Sr2+摄取值低7%或更低。用菜豆（Phaseolus vulgaris L）线粒体观察到碱土金属支持Pi摄取的相同相对顺序。有人提出，植物线粒体中的盐转运涉及一种结合二价阳离子和Pi的载体复合物。
