1QPU

SOLUTION STRUCTURE OF OXIDIZED ESCHERICHIA COLI CYTOCHROME B562

1QPU の概要

• エントリーDOI: 10.2210/pdb1qpu/pdb
• NMR情報: BMRB: 4759
• 分子名称: CYTOCHROME B562, PROTOPORPHYRIN IX CONTAINING FE (2 entities in total)
• 機能のキーワード: four helix bundle, hemoprotein, electron transport
• 由来する生物種: Escherichia coli
• 細胞内の位置: Periplasm: P0ABE7
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 12415.73

構造登録者

Arnesano, F.,Banci, L.,Bertini, I.,Faraone-Mennella, J.,Rosato, A.,Barker, P.D.,Fersht, A.R. (登録日: 1999-05-30, 公開日: 1999-06-02, 最終更新日: 2024-05-22)

主引用文献

Arnesano, F.,Banci, L.,Bertini, I.,Faraone-Mennella, J.,Rosato, A.,Barker, P.D.,Fersht, A.R.
The solution structure of oxidized Escherichia coli cytochrome b562.
Biochemistry, 38:8657-8670, 1999

PubMed Abstract: The solution structure of the oxidized, paramagnetic form of cytochrome b562 from Escherichia coli (106 amino acids) is here reported as obtained from 1653 meaningful NOEs (from a total of 2051 unique NOEs), 33 (3)JHNHalpha values, and 339 pseudocontact shifts. The structure displays the typical four-helix bundle motif, and a disordered loop between helices alpha2 and alpha3, as found in the solid state. The solution structure has a conformation intermediate between the two independent solid-state molecules, although different orientations are observed for a few residues. The magnetic susceptibility tensor is similar to that of cytochrome c, which has the same ligands, although the anisotropy is somewhat smaller. This difference in the electronic structure is consistent with the thermal accessibility in cytochrome b562 of states with S > 1/2. The structure is also compared with the solution structure of the apoprotein, and some information on the role of the cofactor on the protein folding and mobility is obtained. Helix alpha4 seems to be the most sensitive to the chemical environment in terms of structure and mobility. The pKa values affecting the hyperfine-shifted signals are also discussed. Quite intriguing is the comparison of the structure of cytochrome b562 with the available structures of cytochromes c' which display a similar folding motif and similar pKa values but very little sequence similarity.

PubMed: 10393541
DOI: 10.1021/bi982785f

実験手法

SOLUTION NMR