三种红藻光合作用色素系统的比较研究

IOCAS-IR > 海洋环流与波动重点实验室

	三种红藻光合作用色素系统的比较研究
其他题名	三种红藻光合作用色素系统的比较研究
	李映霞
学位类型	博士
导师	王广策
	2007-06-13
学位授予单位	中国科学院海洋研究所
学位授予地点	海洋研究所
学位专业	海洋生物学
关键词	坛紫菜藻胆体类囊体膜条斑紫菜深紫美芒藻
摘要	本研究分为三个部分：1.以坛紫菜（Porphyra haitanesis Chang et Zheng）的叶状体和丝状体为研究对象，比较坛紫菜叶状体和丝状体的光合色素、色素蛋白的组成，并提取纯化藻红蛋白、藻蓝蛋白、藻胆体及类囊体膜和光系统。研究结果表明坛紫菜叶状体和丝状体色素及色素蛋白的含量不同，藻红蛋白是主要的色素蛋白，坛紫菜叶状体和丝状体的藻红蛋白的含量分别为2.9mg藻红蛋白/g鲜重、4.2mg藻红蛋白/g鲜重，这表明坛紫菜叶状体和丝状体藻红蛋白含量丰富，是提取藻红蛋白很好的材料。藻胆体的性质差异不大，但类囊体膜差异显著，从坛紫菜叶状体中分离到了两种不同的类囊体膜带，光系统Ⅰ(PSⅠ)和PSⅡ分别结合在两条类囊体膜带上，但从坛紫菜丝状体中也分离到两条类囊体膜带，它们的光谱性质和蛋白组成相似，仅放氧速率和DCIP活性有差异，从坛紫菜丝状体中我们仅分离到PSⅡ。坛紫菜叶状体PSⅡ有5种外在蛋白(33、20、Cytc 550、15、12kDa蛋白)，而坛紫菜丝状体外在蛋白仅有4条，缺少12kDa蛋白。2. 以在中国江苏部分地区进行了大规模的商业化栽培的突变体条斑紫菜（Porphyra yezoensis Ueda）和野生型条斑紫菜为研究对象，比较其色素及色素蛋白组成、对不能光质的利用率及藻胆体的组成。条斑紫菜和突变型条斑紫菜对不同的光质利用效果有差异，在白光的照射下，野生型紫菜的放氧速率最大，而突变型紫菜在黄光照射下的放氧速率最大。条斑紫菜野生型与突变型色素含量上有明显的差异,突变型紫菜的藻红蛋白含量明显减少而藻蓝蛋白的含量增加。通过杂交的方法证实诱变所获得条斑紫菜突变体为细胞质突变，但是突变型紫菜却发生了由细胞核编码的γ亚基的缺失，这表明突变型紫菜藻红蛋白含量和性质发生了明显的变化。3. 为了找出淡水红藻-深紫美芒藻(Compsopogon coeruleus (Balbis) Montagne)分布狭窄及生物产量低的原因，本文对深紫美芒藻在不同的盐离子浓度下的放氧速率及藻胆体色素组成和结构上进行研究。结果显示：微量的NaCl（0.1mM）促进深紫美芒藻放氧，而深紫美芒藻在较高的NaCl（1、10mM）, NaH2PO4 （0.1、1、10mM）和 NH4NO3（0.1、1、10mM）溶液中却没有检测到氧气的产生。这与深紫美芒藻生长的环境一致即深紫美芒藻生活在低盐浓度、低营养的泉水中。深紫美芒藻的藻胆体是由藻红蛋白、藻蓝蛋白及别藻蓝蛋白组成，上面结合α、β和γ亚基，含有藻红胆素、藻篮胆素，但缺乏缺少藻尿胆素。
其他摘要	This study was divided into three parts: Comparison between leafy gamephyte and free-living conchocelis of Porphyra haitanesis Chang et Zheng in on pigment compositions and isolation of phycoerythrin (PE), phycyanin (PC), phycobilisome, thylakoid membrane and photosystem. The leafy gamephyte and free- living conchocelis of P. haitanesis showed clearly difference in content of pigment. PE was their main pigment protein, and the PE content of P. haitenesis leafy gametophyte and free- living conchocelis were 2.9 and 4.2 mg/ g fw, respectively. The phycobilisomes from leafy gametophyte and free- living conchocelis of P. haitanesis had no significantly different in absorption spectra, fluorescence emission spectra and polypeptide composition. The thylakoid membrane of P. haitanesis leafy gametophyte had two kinds, which consisted of PS Ⅰand PSⅡ, respectively. The extrinsic proteins of PSⅡ included five extrinsic proteins (33, 20, Cytc 550, 15, 12 kDa proteins). In comparison, the thylakoid membranes (B2 and B3) were isolated and purified from free-living conchocelis of P. haitanesis by sucrose density gradient ultracentrifugation. B2 and B3 showed similar absorption and fluorescence emission peaks, while B3 had a relatively higher O2 evolution rates and DCIP photoreduction activities. Intact PSⅡconsisted of four extrinsic proteins previously reported in other red algal PSⅡ particles (33, 20, cytc 550 and 14 kDa proteins). 2. The wile type and gametophytic blade mutant of Porphyra yezoensis Ueda from Porphyra farms in Rudong of China were compared in their composition of pigmentation and phycobilisome. The green mutant was characterized with lower PE and higher PC content in comparison with wide-type. Moreover, the green mutant was resulted from cytoplasmic mutation by crossing the mutant with the wild- type, while this cytoplasmic mutation was absent of γ- subunit of PE, which was encoded by nuclear. 3. In order to investigate the possible effects of the ecological environment on photosynthetic activity and the major light harvesting complex, the oxygen evolution rates and compositions of phycobilisome from freshwater red alga Compsopogon coeruleus (Balbis) Montagne that could grow and reproduce in salinities up to 35 ppt, were studied. Results showed that C. coeruleus tolerated inorganic ion at a relatively lower concentration. The PE from C. coeruleus consisted of α, β and γ subunits, which only carried phycoerythrobilin, phycocyanobilin and absence of phycourobilin, suggesting that PE from C. coeruleus was a new type.
页数	110
语种	中文
文献类型	学位论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/281
专题	海洋环流与波动重点实验室
作者单位	中国科学院海洋研究所
推荐引用方式 GB/T 7714	李映霞. 三种红藻光合作用色素系统的比较研究[D]. 海洋研究所. 中国科学院海洋研究所,2007.