cryo-em structure of the of reaction center light harvesting
complex 1 (rc-lh1) from photosynthetic bacterium
blastochlorisviridis rc-lh1 complex at 2.9 å
dr. puqian（钱朴）
department of molecular biology and biotechnology, the university of sheffield,
sheffield s10 2tn, uk.报告人：
abstract
pore and eventual diffusion to the cytochromebc1 complex. the reaction centre light-harvesting 1 (rc-lh1) complex is the core functional component of bacterial photosynthesis. a 2.9 å resolution cryo-em structure of the bacteriochlorophyllb-based rc-lh1 from blastochlorisviridisreveals the structural basis for absorption of infrared light, and the molecular mechanism of quinone migration across the lh1 complex. the novel triple ring lh1 complex comprises a circular array of 17 β-polypeptides sandwiched between 17 α- and 16 γ-polypeptides. tight packing of the γ-apoproteins between βs collectively interlocks and stabilizes the lh1 structure which, together with the short mg-mg distances of bchlb pairs, contributes to the large red-shift of bacteriochlorophyllb absorption. the ‘missing’ 17th γ polypeptide creates a pore in the lh1 ring, and an adjacent binding pocket provides a folding template for a novel quinone, qp, which adopts a compact, export-ready conformation prior to passage through the
个人简介：
puqian is a professor (part-time), school of life science, suzhou university and research associate of department of molecular biology & biotechnology, the university of sheffield, uk. his main research work are high resolution structures of light harvesting core complexes from photosynthetic bacteria using cryo-em. his expertise include protein purification, 2d/3d crystallizations, em measurement, data processing and presentation. 2d electron crystallography, x-ray crystallography and cryo-em single particle analysis have been employed for structure determination of membrane proteins. during the last decade, he published a series of papers on the structure determination of rc-lh1 core complexes from photosynthetic bacteria. recently, a 2.9 å resolution cryo-em structure of the core complexes from blastochlorisviridiswild was accepted by nature as an article. this structure revealed a new architecture of the rc-lh1 core complex from photosynthetic bacteria, explained its large red-shift absorption of bacteriochlorophyll b in the complex and mechanism of quinone / quinol
