Carotenoid cation formation and the regulation of photosynthetic light harvesting

被引：643

作者：

Holt, NE

Zigmantas, D

Valkunas, L

Li, XP

Niyogi, KK

Fleming, GR ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA

[2] Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA

[3] Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA

来源：

SCIENCE | 2005年 / 307卷 / 5708期

关键词：

D O I：

10.1126/science.1105833

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Photosynthetic light harvesting in excess light is regulated by a process known as feedback deexcitation. Femtosecond transient absorption measurements on thylakoid membranes show selective formation of a carotenoid radical cation upon excitation of chlorophyll under conditions of maximum, steady-state feedback deexcitation. Studies on transgenic Arabidopsis thaliana plants confirmed that this carotenoid radical cation formation is correlated with feedback deexcitation and requires the presence of zeaxanthin, the specific carotenoid synthesized during high light exposure. These results indicate that energy transfer from chlorophyll molecules to a chlorophyll-zeaxanthin heterodimer, which then undergoes charge separation, is the mechanism for excess energy dissipation during feedback deexcitation.

引用

页码：433 / 436

页数：4

共 25 条

[1] TOO MUCH OF A GOOD THING - LIGHT CAN BE BAD FOR PHOTOSYNTHESIS [J].