重组别藻蓝蛋白三聚体结构与功能

doi:doi: 10.1360/N972016-01416

CORC > 烟台海岸带研究所 > 中国科学院烟台海岸带研究所 > 海岸带生物学与生物资源利用重点实验室 > 海岸带生物学与生物资源利用所重点实验室

	重组别藻蓝蛋白三聚体结构与功能
	李文军 ; 蒲洋 ; 牛壮 ; 薛春岭 ; 秦松
刊名	科学通报
	2017-06-10
卷号	62 期号:16 页码:1699-1713
关键词	recombinant allophycocyanin trimer exciton-coupled pairs absorption spectrum fluorescence spectrum circular dichroism spectra conformational stability 重组别藻蓝蛋白三聚体激子耦合对吸收光谱荧光光谱圆二色谱构象稳定性
ISSN号	0023-074X
DOI	doi: 10.1360/N972016-01416
其他题名	Structural and functional investigation of allophycocyanin trimer
产权排序	(1) 中国科学院烟台海岸带研究所 ; (2) 中国科学院大学 ; (3) 鲁东大学农学院
文献子类	Article
英文摘要	Nature has been developing and optimizing photosynthesis billions years, including green plants, algae, photosynthetic bacteria and cyanobacteria. Phycobiliproteins system, as the phycobilisomes, in cyanobacteria and red algae is the one of two major light-harvesting systems, after evolution in billions years. Allophycocyanin (APC) trimer is a primary composition of phycobilisomes core for efficient lower-energy photons funneling pathway. In 2009, Liu et al. have firstly assembled the highly soluble self-assembled recombinant APC trimer with N-terminus polyhistidine, which the entire biosynthesis pathway of APC trimer was reconstituted in Escherichia coli strain with the full-length genes of apoprotein a subunit and b subunit from Synechocystis sp. PCC 6803. The recombinant APC trimer was used to be the subject in this research. An optimum protocol with immobilized metal-ion affinity chromatography with chelating transition metal ion (Ni~(2+)) was used to purify the recombinant protein. Then, the second purification was performed to obtain APC trimer with a higher purity (A650/A620=1.346), using density gradient centrifugation. Single molecules of recombinant APC trimers were investigated with atomic force microscopy. Three-dimensional images with resolution at nanoscale indicated that the recombinant allophycocyanin trimers were approximately 1.5 nm in short axis, and 15 nm in long axis, which were in accordance with the sizes of natural allophycocyanin trimer measured by transmission electron microscopy or X-ray crystallography. Moreover, the correct conformation of recombinant allophycocyanin trimer was confirmed by fluorescence spectra (studied energy transfer ability), absorption spectra (studied the light-harvesting ability), and circular dichroism (CD) spectra (studied changes of secondary structure and aggregation state). The CD spectra of recombinant allophycocyanin induced by a wide range of pH were analyzed both at wavelengths in ultraviolet range (190-250 nm) and visible range (450-750 nm). The a-helices were the dominant secondary structure in recombinant allophycocyanin trimer by analysis of CD spectra in ultraviolet range, while the analysis of CD spectra in visible range suggested the existence of exciton-coupled pairs of phycocyanobilins, in which the energy transfer was mainly in the form of exciton splitting. By studying its spectra property variations in response to pH changes, we found that recombinant APC trimer showed good absorbance and fluorescence stability at varying pH. The conformation of chromophores in recombinant APC trimer was relatively stable, between the range of pH 4-9, which was revealed by the stable absorption and fluorescence spectra properties of recombinant APC trimer. The trimeric structure of recombinant APC was maintained while local variations of protein peptides were also shown in response to the environmental disturbance. Beyond this pH range, secondary structure as well as overall conformation of recombinant APC dramatically changed, and the energy absorption and transfer ability were also disrupted. This work demonstrated that correct function in energy transfer was retained in the recombinant allophycocyanin trimer compared with nature allophycocyanin trimer.
WOS关键词	Plant Sciences
WOS研究方向	Plant Sciences ; 植物科学
语种	中文
CSCD记录号	CSCD:6003393
内容类型	期刊论文
源URL	[http://ir.yic.ac.cn/handle/133337/24307]
专题	烟台海岸带研究所_海岸带生物学与生物资源利用所重点实验室
作者单位	1.中国科学院烟台海岸带研究所; 2.中国科学院大学; 3.鲁东大学农学院
推荐引用方式 GB/T 7714	李文军,蒲洋,牛壮,等. 重组别藻蓝蛋白三聚体结构与功能[J]. 科学通报,2017,62(16):1699-1713.
APA	李文军,蒲洋,牛壮,薛春岭,&秦松.(2017).重组别藻蓝蛋白三聚体结构与功能.科学通报,62(16),1699-1713.
MLA	李文军,et al."重组别藻蓝蛋白三聚体结构与功能".科学通报 62.16(2017):1699-1713.