【摘要】 我们测定了不同条件下小麦幼苗叶绿体的锰的EPR谱。它们与Mn²⁺谱线的特征完全一致。一部分锰可与EDTA螯合。光照使其信号减小50—60％,而在黑暗中又恢复。放氧抑制剂DCMU亦能抑制锰的这种可逆变化。这些结果表明部分锰与放氧有关。我们也观察了不同温度的热处理对释出类囊体膜上结合锰的相对量的影响,发现90℃加热释出的结合锰占总结合锰的20％。我们讨论了类囊体内各类锰的相对量及其在光合作用中的功能。更多还原

【Abstract】 The manganese-electron paramagnetic resonance (Mn2+-EPR) signals in chlo-roplasts of wheat seedling under different conditions have been measured. Their characteristics were the same as that of MnCl2 standard solution. This part of Mn2+ could be chelated by EDTA. By light, Mn2+-EPR signal was decreased by 50-60% of Mn2+-EPR signal in the dark. The light effect was reversible. Mn2+-EPR signal was also effected by O2-evolving inhibitor DCMU. This result provided that a part of Mn associated with O2 evolution system. We also examined the effects of heat treatments at diffrent temperatures on the releasing of membrane-hounded Mn2+ on thylakoid and found that the 20% of total bound Mn was released by heat treatment at 90℃. The relative amounts of membrane-bounded Mn2+ in thylakoid and their functions in photosynthesis have been discussed.更多还原