Electron tunneling in rhenium-modified Pseudomonas aeruginosa azurins
2004 (English)In: Biochimica et Biophysica Acta - Bioenergetics, ISSN 0005-2728, E-ISSN 1879-2650, Vol. 1655, no 1-3, 59-63 p.Article in journal (Refereed) Published
Laser flash-quench methods have been used to generate tyrosine and tryptophan radicals in structurally characterized rhenium-modified Pseudomonas aeruginosa azurins. Cu(I) to “Re(II)” electron tunneling in Re(H107) azurin occurs in the microsecond range. This reaction is much faster than that studied previously for Cu(I) to Ru(III) tunneling in Ru(H107) azurin, suggesting that a multistep (“hopping”) mechanism might be involved. Although a Y108 radical can be generated by flash-quenching a Re(H107)M(II) (M=Cu, Zn) protein, the evidence suggests that it is not an active intermediate in the enhanced Cu(I) oxidation. Rather, the likely explanation is rapid conversion of Re(II)(H107) to deprotonated Re(I)(H107 radical), followed by electron tunneling from Cu(I) to the hole in the imidazole ligand.
Place, publisher, year, edition, pages
2004. Vol. 1655, no 1-3, 59-63 p.
Electron tunneling, Rhenium complex, Amino acid radical, Blue copper, Azurin
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-85311DOI: 10.1016/j.bbabio.2003.06.010OAI: oai:DiVA.org:liu-85311DiVA: diva2:568073