Depletion of phosphatidyl-glycerol head-group induces changes in oxygen evolution and protein secondary structures of photosystem Ⅱ  

作　　者：YANG Zhenle, WANG Zeneng, JIANG Guizhen, XU Yinong, LI Liangbi & KUANG TingyunPhotosynthesis Research Center, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 

出　　处：《Chinese Science Bulletin》2002年第10期824-829,共6页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant No. 39890390); the State Basic Research Development Plan of China (Grant No. G1998010100);the Innovative Foundation of Laboratory of Photosynthesis Basic Research, Insti

摘　　要：The techniques of oxygen electrode polarogra-phy and Fourier transform infrared (FT-IR) spectroscopy were employed to explore the roles of polar head-group of phosphatidylglycerol (PG) molecules in the functional and structural aspects of photosystem Ⅱ (PS Ⅱ) through enzymatic approach. It was shown that the depletion of PG by treatment of phospholipase C (PLC) on PS Ⅱ particles caused the inhibition of oxygen evolving activity in PS Ⅱ. This effect also gave rise to changes in the protein secondary structures of PS Ⅱ, that is, an increase in a-helical conformation which is compensated by the loss of p-strand structures. It revealed that the head-group of PG molecules plays an important structural role in the maintenance of normal structure of PS Ⅱ proteins, which is required to maintain the appropriate physiological activity of the PS Ⅱ complex such as the oxygen evolving activity. It is suggested that there most probably exist hydrogen-bonding interactions between PG molecules and PS Ⅱ proteins.The techniques of oxygen electrode polarogra-phy and Fourier transform infrared (FT-IR) spectroscopy were employed to explore the roles of polar head-group of phosphatidylglycerol (PG) molecules in the functional and structural aspects of photosystem Ⅱ (PS Ⅱ) through enzymatic approach. It was shown that the depletion of PG by treatment of phospholipase C (PLC) on PS Ⅱ particles caused the inhibition of oxygen evolving activity in PS Ⅱ. This effect also gave rise to changes in the protein secondary structures of PS Ⅱ, that is, an increase in a-helical conformation which is compensated by the loss of p-strand structures. It revealed that the head-group of PG molecules plays an important structural role in the maintenance of normal structure of PS Ⅱ proteins, which is required to maintain the appropriate physiological activity of the PS Ⅱ complex such as the oxygen evolving activity. It is suggested that there most probably exist hydrogen-bonding interactions between PG molecules and PS Ⅱ proteins.

关 键 词：PHOTOSYSTEM II polar head-group of phosphatidylglyc-erol PHOSPHOLIPASE C oxygen evolution protein secondary struc-ture. 

分 类 号：Q945[生物学—植物学]