Abstract:

Peptide composition and arrangement of 4 major light harvesting complexes LHCP1-3 and LHCP3′isolated from siphonous green algae （Codium fragile (Sur.) Hariot.） were investigated. LHCP1 showed five main peptides, 34.4, 31.5, 29.5, 28.2 and 26.5 kD in SDS PAGE, the 34.4 and 31.5 kD peptides were never found in higher plants. LHCP3 contained the other four kinds of LHCP1 peptides except 34.4 kD, while LHCP3′consisted of only 28.2 and 26.5 kD peptides. We found that 34.4, 28.2 and 26.5 kD peptides were easy to decompose from LHCP 1 when subjected to SDS PAGE without pretreatment. They might be located at the exterior of LHCP1, while the 31.5 and 29.5 kD peptides were at the central part. The 28.2 and 26.5 kD peptides often occurred in CPa, the center complex of PSⅡ. They are possibly the LHCⅡ peptides tightly associated with CCⅡ. According to the results described above, a peptide map of LHCP1 was sketched.

管藻目绿藻刺松藻PSⅡ捕光复合物多肽结构分析

陈敏^1*  李爱芬¹  周百成²

(1. 烟台大学生物化学系,烟台 264005；2. 中国科学院海洋研究所,青岛 266071)

摘要：对管藻目绿藻刺松藻(Codium fragile (Sur.) Hariot.)的4种主要的捕光复合物LHCP1-3和LHCP3′的多肽组成和相互关系进行了研究.LHCP1在SDS-PAGE中主要呈现34.4、31.5、29.5、28.2和26.5 kD 5种多肽,其中34.4和31.5 kD多肽是高等植物所没有的;LHCP3含有LHCP1中除了34.4 kD多肽以外的其他4种多肽,而LHCP3′只含有28.2和26.5 kD两种多肽.若LHCP1不经处理直接进行SDS-PAGE,发现较易从LHCP1上脱落的是34.4、28.2和26.5 kD多肽,这表明它们可能位于较外侧,而31.5和29.5 kD多肽则靠近核心;28和26 kD两种多肽常出现在刺松藻的中心复合物CPa中,可能是与CCⅡ结合最为紧密的LHCⅡ多肽.根据上述结果提出了1个LHCP1多肽结构关系示意图.

关键词 捕光复合物 多肽 结构 刺松藻

*通讯作者 Email: chenmclm@china.com

Key words: light harvesting complexes, peptide arrangement, structure, Codium fragile