摘要
假根羽藻(Bryopsis corticulans)的叶绿素-蛋白质复合物组分和菠菜(Spinaceaoleracia)的比较较为简单,含有较多的叶绿素b和其他辅助色素,而且它们大多集中在光系统Ⅱ的捕光叶绿素-蛋白质复合物中。叶绿素的分布也不均匀。两种植物复合物的吸收光谱存在差异。假根羽藻含有管藻素和管藻黄素。假根羽藻叶绿素-蛋白质复合物载体蛋白的分子量大于菠菜相应组分的分子量。
Absorption properties,pigment compositions,Chl a/b ratios and apparent molecular weights of chlorophyll-protein complexes were compared between spinach and a marine green alga,Bryopsis corticulans.The results are as follows: 1.Ten chlorophyll-protein complexes were resolved from spinach thylakoid membranes solubilized by SDS in a final SDS/Chl weight ratio of 10:1,and subjected to SDS-PAGE with 11% resolution gel.CPla 1—3 and CPI belonged to photosystem I,and the rest to photosystem II.The maximum absorption of CPIa^2,CPla^3 and CPl were all at 674nm,but that of CPla^1 at 670nm,and those of LHCII and D_2 at 670 and 673nm,respectively.Chlorophyll in PSlI was 63% of the total.In PSII,most of chlorophyll was in LHCII which contained 86% of the chlorophyll in PSII.In PSI,chlorophyll in CPIa was 72% of the total.Chlorophyll a was the main pigment in PSI components which have Chl a/b ratio over 15. 2.Eight chlorophyll-protein complexes were isolated from B.corticulans with a SDS/Chl weight ratio of 8:1 and 8% resolution gel.The maximum absorption of CPIa,CPI,LHCII and D_2 were respectively at 671nm,673nm,669nm and 664nm.PSII contained 77% of the total chlorophyll.LHCII chlorophyll was 95% of the PSII chlorophyll.CPI held 77% of PSI chlorophyll. There was more chlorophyll b in Bryopsis complexes,especially in LHCII (Chl a/b< 0.8).The molecular weights of Bryopsis complexes were higher than those of the spinach complexes. Bryopsis LHCII contained siphoxanthin and siphothin,the marked pigments of Siphonales, as functional pigments.The above results revealed three points of difference between these two plants.Firstly,Chl a is the main pigment in spinach,whereas in Bryopsis the main pigments are Chl b and siphoxanthin.This is in accordance with the suggestion that plants may change their pigment composition to adapt light regime in the environment during evolution. Secondly,in Bryopsis,chlorophyll is concentrated in photosystem II,but in spinach chlorophyll is shared evenly by two photosystems.Finally,CPI in Bryopsis contained the major part of chlorophyll in PSI,yet in spinach CPIa is the superior.
基金
国家自然科学基金资助项目
关键词
假根习藻
菠菜
叶绿素蛋白质
进化
Bryopsis coniculans
Spinach
Chlorophyll-Proteins
Evolution
