Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers

	Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers
	Long, Saran 1,2; Zhou, Meng 1,2; Tang, Kun 3; Zeng, Xiao-Li 3; Niu, Yingli 1,2; Guo, Qianjin 1,2; Zhao, Kai-Hong 3; Xia, Andong 1,2
刊名	PHYSICAL CHEMISTRY CHEMICAL PHYSICS
	2015
卷号	17 期号:20 页码:13387-13396
英文摘要	ApcE(1-240) dimers with one intrinsic phycocyanobilin (PCB) chromophore in each monomer that is truncated from the core-membrane linker (ApcE) of phycobilisomes (PBS) in Nostoc sp. PCC 7120 show a sharp and significantly red-shifted absorption. Two explanations either conformation-dependent Forster resonance energy transfer (FRET) or the strong exciton coupling limit have been proposed for red-shifted absorption. This is a classic example of the special pair in the photosynthetic light harvesting proteins, but the mechanism of this interaction is still a matter of intense debate. We report the studies using single-molecule and transient absorption spectra on the interaction in the special pair of ApcE dimers. Our results demonstrate the presence of conformation-dependent FRET between the two PCB chromophores in ApcE dimers. The broad distributions of fluorescence intensities, lifetimes and polarization difference from single-molecule measurements reveal the heterogeneity of local protein-pigment environments in ApcE dimers, where the same molecular structures but different protein environments are the main reason for the two PCB chromophores with different spectral properties. The excitation energy transfer rate between the donor and the acceptor about (110 ps)(-1) is determined from transient absorption measurements. The red-shifted absorption in ApcE dimers could result from more extending conformation, which shows another type of absorption redshift that does not depend on strong exciton coupling. The results here stress the importance of conformation-controlled spectral properties of the chemically identical chromophores, which could be a general feature to control energy/electron transfer, widely existing in the light harvesting complexes.
收录类别	SCI
语种	英语
公开日期	2016-05-09
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/28076]
专题	化学研究所_光化学实验室
作者单位	1.Chinese Acad Sci, Beijing Natl Lab Mol Sci, Inst Chem, Beijing 100190, Peoples R China 2.Chinese Acad Sci, Key Lab Photochem, Inst Chem, Beijing 100190, Peoples R China 3.Huazhong Agr Univ, State Key Lab Agr Microbiol, Wuhan 430070, Peoples R China
推荐引用方式 GB/T 7714	Long, Saran,Zhou, Meng,Tang, Kun,et al. Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers[J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS,2015,17(20):13387-13396.
APA	Long, Saran.,Zhou, Meng.,Tang, Kun.,Zeng, Xiao-Li.,Niu, Yingli.,...&Xia, Andong.(2015).Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers.PHYSICAL CHEMISTRY CHEMICAL PHYSICS,17(20),13387-13396.
MLA	Long, Saran,et al."Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers".PHYSICAL CHEMISTRY CHEMICAL PHYSICS 17.20(2015):13387-13396.