2BC5

Crystal structure of E. coli cytochrome b562 with engineered c-type heme linkages

2BC5 の概要

• エントリーDOI: 10.2210/pdb2bc5/pdb
• 関連するPDBエントリー: 256B
• 分子名称: Soluble cytochrome b562, SULFATE ION, HEME C, ... (4 entities in total)
• 機能のキーワード: four-helix bundle, k59w, r98c and y101c mutations, 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: 4
• 化学式量合計: 50307.34

構造登録者

Faraone-Mennella, J.,Tezcan, F.A.,Gray, H.B.,Winkler, J.R. (登録日: 2005-10-18, 公開日: 2006-09-26, 最終更新日: 2024-11-06)

主引用文献

Faraone-Mennella, J.,Tezcan, F.A.,Gray, H.B.,Winkler, J.R.
Stability and Folding Kinetics of Structurally Characterized Cytochrome c-b(562).
Biochemistry, 45:10504-10511, 2006

PubMed Abstract: The four-helix-bundle protein fold can be constructed from a wide variety of primary amino acid sequences. Proteins with this structure are excellent candidates for investigations of the relationship between folding mechanism and topology. The folding of cytochrome b(562), a four-helix-bundle heme protein, is hampered by heme dissociation. To overcome this complication, we have engineered a variant of cytochrome b(562) (cyt c-b(562)) featuring a c-type linkage between the heme and the polypeptide chain. The replacement of the native cyt b(562) leader sequence in this protein with that of a c-type cytochrome (cyt c(556)) led to high yields of fully matured and correctly folded cyt c-b(562). We have determined the X-ray crystal structure of cyt c-b(562) at 2.25 A and characterized its physical, chemical, and folding properties. These measurements reveal that the c-type linkage does not perturb the protein fold or reduction potential of the heme group. The covalent attachment of the porphyrin to the polypeptide does, however, produce a substantial change in protein stability and folding kinetics.

PubMed: 16939202
DOI: 10.1021/bi060242x

実験手法

X-RAY DIFFRACTION (2.25 Å)