1C2R

MOLECULAR STRUCTURE OF CYTOCHROME C2 ISOLATED FROM RHODOBACTER CAPSULATUS DETERMINED AT 2.5 ANGSTROMS RESOLUTION

1C2R の概要

• エントリーDOI: 10.2210/pdb1c2r/pdb
• 分子名称: CYTOCHROME C2, HEME C (3 entities in total)
• 機能のキーワード: electron transport protein (cytochrome)
• 由来する生物種: Rhodobacter capsulatus
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 25809.03

構造登録者

Benning, M.M.,Wesenberg, G.,Caffrey, M.S.,Bartsch, R.G.,Meyer, T.E.,Cusanovich, M.A.,Rayment, I.,Holden, H.M. (登録日: 1991-03-19, 公開日: 1992-01-15, 最終更新日: 2024-10-23)

主引用文献

Benning, M.M.,Wesenberg, G.,Caffrey, M.S.,Bartsch, R.G.,Meyer, T.E.,Cusanovich, M.A.,Rayment, I.,Holden, H.M.
Molecular structure of cytochrome c2 isolated from Rhodobacter capsulatus determined at 2.5 A resolution.
J.Mol.Biol., 220:673-685, 1991

PubMed Abstract: The molecular structure of the cytochrome c2, isolated from the purple photosynthetic bacterium Rhodobacter capsulatus, has been solved to a nominal resolution of 2.5 A and refined to a crystallographic R-factor of 16.8% for all observed X-ray data. Crystals used for this investigation belong to the space group R32 with two molecules in the asymmetric unit and unit cell dimensions of a = b = 100.03 A, c = 162.10 A as expressed in the hexagonal setting. An interpretable electron density map calculated at 2.5 A resolution was obtained by the combination of multiple isomorphous replacement with four heavy atom derivatives, molecular averaging and solvent flattening. At this stage of the structural analysis the electron densities corresponding to the side-chains are well ordered except for several surface lysine, glutamate and aspartate residues. Like other c-type cytochromes, the secondary structure of the protein consists of five alpha-helices forming a basket around the heme prosthetic group with one heme edge exposed to the solvent. The overall alpha-carbon trace of the molecule is very similar to that observed for the bacterial cytochrome c2, isolated from Rhodospirillum rubrum, with the exception of a loop, delineated by amino acid residues 21 to 32, that forms a two stranded beta-sheet-like motif in the Rb. capsulatus protein. As observed in the eukaryotic cytochrome c proteins, but not in the cytochrome c2 from Rsp. rubrum, there are two evolutionarily conserved solvent molecules buried within the heme binding pocket.

PubMed: 1651396
DOI: 10.1016/0022-2836(91)90109-J

実験手法

X-RAY DIFFRACTION (2.5 Å)