IAA及KCN在黄瓜子叶离体叶绿体氧化还原作用过程中的相互作用  

The action and the interaction of IAA and KCN during the photoreduoxidation of cucumber cotyledon chloroplasts

作　　者：浦铜良[1] 程佑发[1] 张承烈[1] 

机构地区：[1]兰州大学生物系,兰州730000

出　　处：《西北植物学报》2000年第3期358-363,共6页Acta Botanica Boreali-Occidentalia Sinica

摘　　要：IAA对于不同时期的叶绿体 DCPIP光还原均有促进效应。而对叶绿体的放氧效率的促进则随子叶叶龄的增长而下降至零。 CN- ( 1 0 - 3mol/L)存在时不同程度地抑制叶绿体的DCPIP光还原和氧化放氧。而 IAA( 1 0 - 5、1 0 - 4mol/L)则能消除 CN- 的抑制作用而仅表现IAA原有的促进作用。同时 ,IAA可以释放照光和不照光条件下 KCN对离体叶绿体分解外源 H2 O2 的抑制。叶绿体光系统的光还原和 H2 O的光解放氧在时间上可通过累积特定的中间产物 (可能为 H2 O2 )而分离。这在较为衰老的子叶叶绿体上尤为明显。Purified cucumber cotyledon chloroplasts were treated with IAA (<10 -4 mol/L) and/or KCN (10 -3 mol/L).IAA would promote the DCPIP photoreduction by the chloroplasts from 6 d and 16 d cotyledon.But the promotion to the oxidable oxygen release was less and would decline gradually to as far as zero when the cotyledon became older.So there was a disagreement between the promotion levels of the DCPIP photoreduction and O 2 release.A similar disagreement also existed especially on the 16 d cotyledon chloroplasts.KCN would depress both the DCPIP photoreduction and the photosynthetic O 2 release by the chloroplasts from 6 d and 16 d cotyledon.But IAA could almost totally reverse the depression and demonstrated its original promotion.It is concluded that the photoreduction and the O 2 release could be separated on time by accumulating certain intermediate,probably H 2O 2.IAA could release the KCN depress on the H 2O 2 decomposition by the chloroplasts but could not promote it.

关 键 词：光合电子链 IAA KCN 叶绿体 氧化还原 

分 类 号：Q945.11[生物学—植物学]