Sarry J E, Montillet J L, Sauvaire Y, Havaux M
Département de Physiologie Végétale et Ecosystèmes, CEA, Sciences du Vivant, Saint-Paul-lez-Durance, France.
FEBS Lett. 1994 Oct 17;353(2):147-50. doi: 10.1016/0014-5793(94)01028-5.
The rapid conversion of the carotenoid violaxanthin to zeaxanthin via antheraxanthin (xanthophyll cycle) in potato leaves exposed at 23 degrees C to a strong white light of 2000 microE.m-2.s-1 was associated with a slight inhibition of photosynthetic electron transport (as estimated from chlorophyll fluorescence measurements) and a low lipid peroxidation (as estimated from ethane measurements). When the xanthophyll cycle was blocked by dithiothreitol (3 mM) or low temperature (3 degrees C), photoinhibition of electron transport was exacerbated and pronounced lipid peroxidation occurred concomitantly. Accumulation of zeaxanthin and antheraxanthin in potato leaves by a non-photoinhibitory light treatment at 23 degrees C (900 microE.m-2.s-1 for 1 h) considerably reduced the level of lipid peroxidation during subsequent light stress at 3 degrees C. The presented results indicate that one of the functions of the xanthophyll cycle could be the protection of thylakoid membranes against lipid peroxidation, suggesting that zeaxanthin and antheraxanthin synthesized in strong light are present as free pigments in the membrane lipid bilayer.
在23摄氏度下暴露于2000微爱因斯坦·米-2·秒-1的强光下的马铃薯叶片中，类胡萝卜素紫黄质通过环氧玉米黄质迅速转化为玉米黄质（叶黄素循环），这与光合电子传递的轻微抑制（通过叶绿素荧光测量估算）和低脂质过氧化作用（通过乙烷测量估算）相关。当叶黄素循环被二硫苏糖醇（3 mM）或低温（3摄氏度）阻断时，电子传递的光抑制加剧，同时发生明显的脂质过氧化。在23摄氏度（900微爱因斯坦·米-2·秒-1，处理1小时）下通过非光抑制性光照处理使马铃薯叶片中玉米黄质和环氧玉米黄质积累，这在随后3摄氏度的光胁迫期间显著降低了脂质过氧化水平。所呈现的结果表明，叶黄素循环的功能之一可能是保护类囊体膜免受脂质过氧化，这表明在强光下合成的玉米黄质和环氧玉米黄质作为游离色素存在于膜脂双层中。
