Long‐range intramolecular electron transfer in Rhus vernicifera stellacyanin: A pulse radiolysis study

FEBS Letters

Farver, Ole¹  Pecht, Israel² 

[1] Department of Physical Chemistry, Royal Danish School of Pharmacy, 2, Universitetsparken, DK-2100 Copenhagen Ø, Denmark;Department of Chemical Immunology, The Weizmann Institute of Science, 76100 Rehovot, Israel

关键词: Blue copper protein;    Stellacyanin;    Pulse radiolysis;    St;    stellacyanin;    a;    NH3;   

DOI  :  10.1016/0014-5793(89)80567-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The (NH₃)₅Ru-modified stellacyanin Ru(III)₂-St[Cu(II)], where two ruthenium ions are coordinated to imidazole residues of His-32 and 100, has been synthesized. CO⁻ ₂ radicals, generated by pulse radiolysis, react with the modified protein yielding an intermediate Ru(II)-St[Cu(II)]. The rate of molecular electron transfer within this complex Ru(II)-St[Cu(II)] ^k Ru(III)-St[Cu(I)] has been determined, k _u = 0.05 s⁻¹ at 18°C, pH 7.0. The Ru(His-32/100) to Cu(II) separation distance is relatively large (∼ 18 Å), and the driving force is low (10 kJ·mol⁻¹), hence the correspondingly slow rate. This result is compared with those obtained in earlier studies of intramolecular fixed-distance electron transfer reactions in blue copper proteins.

【 授权许可】

Unknown