1RCY

RUSTICYANIN (RC) FROM THIOBACILLUS FERROOXIDANS

1RCY の概要

• エントリーDOI: 10.2210/pdb1rcy/pdb
• 分子名称: RUSTICYANIN, COPPER (II) ION (3 entities in total)
• 機能のキーワード: metalloprotein, copper containing protein, oxidation potential, ph stability, redox protein
• 由来する生物種: Acidithiobacillus ferrooxidans
• 細胞内の位置: Periplasm: P24930
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 16261.05

構造登録者

Walter, R.L.,Friedman, A.M.,Ealick, S.E.,Blake II, R.C.,Proctor, P.,Shoham, M. (登録日: 1996-04-10, 公開日: 1997-05-15, 最終更新日: 2024-02-14)

主引用文献

Walter, R.L.,Ealick, S.E.,Friedman, A.M.,Blake 2nd., R.C.,Proctor, P.,Shoham, M.
Multiple wavelength anomalous diffraction (MAD) crystal structure of rusticyanin: a highly oxidizing cupredoxin with extreme acid stability.
J.Mol.Biol., 263:730-751, 1996

PubMed Abstract: The X-ray crystal structure of the oxidized form of the extremely stable and highly oxidizing cupredoxin rusticyanin from Thiobacillus ferrooxidans has been determined by the method of multiwavelength anomalous diffraction (MAD) and refined to 1.9 A resolution. Like other cupredoxins, rusticyanin is a copper-containing metalloprotein, which is composed of a core beta-sandwich fold. In rusticyanin the beta-sandwich is composed of a six- and a seven-stranded beta-sheet. Also like other cupredoxins, the copper ion is coordinated by a cluster of four conserved residues (His85, Cys138, His143, Met148) arranged in a distorted tetrahedron. Rusticyanin has a redox potential of 680 mV, roughly twice that of any other cupredoxin, and it is optimally active at pH values < or = 2. By comparison with other cupredoxins, the three-dimensional structure of rusticyanin reveals several possible sources of the chemical differences, including more ordered secondary structure and more intersheet connectivity than other cupredoxins. The acid stability and redox potential of rusticyanin may also be enhanced over other cupredoxins by a more extensive internal hydrogen bonding network and by more extensive hydrophobic interactions surrounding the copper binding site. Finally, reduction in the number of charged residues surrounding the active site may also make a major contribution to acid stability. We propose that the resulting rigid copper binding site, which is constrained by the surrounding hydrophobic environment, structurally and electronically favours Cu(I). We propose that the two extreme chemical properties of rusticyanin are interrelated; the same unique structural features that enhance acid stability also lead to elevated redox potential.

PubMed: 8947572
DOI: 10.1006/jmbi.1996.0612

実験手法

X-RAY DIFFRACTION (1.9 Å)