3G7F

Crystal structure of Blastochloris viridis heterodimer mutant reaction center

3G7F の概要

• エントリーDOI: 10.2210/pdb3g7f/pdb
• 分子名称: Photosynthetic reaction center cytochrome c subunit, BACTERIOPHEOPHYTIN B, UBIQUINONE-1, ... (15 entities in total)
• 機能のキーワード: heterodimer mutant, blastochloris viridis, photosynthetic reaction center, membrane protein structure, microfluidics, plugs, cell membrane, electron transport, heme, iron, lipoprotein, membrane, metal-binding, photosynthesis, reaction center, transport, bacteriochlorophyll, chlorophyll, chromophore, formylation, transmembrane, magnesium
• 由来する生物種: Blastochloris viridis; 詳細
• 細胞内の位置: Cell membrane; Lipid-anchor: P07173; Cellular chromatophore membrane; Single-pass membrane protein: P06008; Cellular chromatophore membrane; Multi-pass membrane protein (By similarity): P06009 P06010
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 145584.97

構造登録者

Ponomarenko, N.S.,Li, L.,Tereshko, V.,Ismagilov, R.F.,Norris Jr., J.R. (登録日: 2009-02-09, 公開日: 2009-09-22, 最終更新日: 2024-11-20)

主引用文献

Ponomarenko, N.S.,Li, L.,Marino, A.R.,Tereshko, V.,Ostafin, A.,Popova, J.A.,Bylina, E.J.,Ismagilov, R.F.,Norris, J.R.
Structural and spectropotentiometric analysis of Blastochloris viridis heterodimer mutant reaction center
Biochim.Biophys.Acta, 1788:1822-1831, 2009

PubMed Abstract: Heterodimer mutant reaction centers (RCs) of Blastochloris viridis were crystallized using microfluidic technology. In this mutant, a leucine residue replaced the histidine residue which had acted as a fifth ligand to the bacteriochlorophyll (BChl) of the primary electron donor dimer M site (HisM200). With the loss of the histidine-coordinated Mg, one bacteriochlorophyll of the special pair was converted into a bacteriopheophytin (BPhe), and the primary donor became a heterodimer supermolecule. The crystals had dimensions 400 x 100 x 100 microm, belonged to space group P4(3)2(1)2, and were isomorphous to the ones reported earlier for the wild type (WT) strain. The structure was solved to a 2.5 A resolution limit. Electron-density maps confirmed the replacement of the histidine residue and the absence of Mg. Structural changes in the heterodimer mutant RC relative to the WT included the absence of the water molecule that is typically positioned between the M side of the primary donor and the accessory BChl, a slight shift in the position of amino acids surrounding the site of the mutation, and the rotation of the M194 phenylalanine. The cytochrome subunit was anchored similarly as in the WT and had no detectable changes in its overall position. The highly conserved tyrosine L162, located between the primary donor and the highest potential heme C(380), revealed only a minor deviation of its hydroxyl group. Concomitantly to modification of the BChl molecule, the redox potential of the heterodimer primary donor increased relative to that of the WT organism (772 mV vs. 517 mV). The availability of this heterodimer mutant and its crystal structure provides opportunities for investigating changes in light-induced electron transfer that reflect differences in redox cascades.

PubMed: 19539602
DOI: 10.1016/j.bbamem.2009.06.006

実験手法

X-RAY DIFFRACTION (2.5 Å)