Enantio selectivity of resolved Delta and Lambda orthoruthenated 2-phenylpyridine complexes Ru(o-C6H4-2-py)(LL)(2) PF6 (LL = bpy and phen) toward glucose oxidase
2006 (English)In: Journal of Molecular Catalysis B: Enzymatic, ISSN 1381-1177, Vol. 41, no 04-mar, 110-116 p.Article in journal (Refereed) Published
Cyclometalated 2-phenylpyridine complexes [Ru-II(o-C6H4-2-py)(LL)(2)]PF6, LL=2,2'-bipyridine (1) and 1,10-phenanthroline (2) were resolved into A and A enantiomers using column chromatography on SP Sephadex C-25 in the presence of (+)-2,3-dibenzoyl-D-tartrate. The absolute configuration of enantiomers was established using circular dichroism spectroscopy. The rate constants k(et) for the electron transfer from reduced glucose oxidase (GO from Aspergillus niger) and PQQ-dependent glucose dehydrogenase (GDH) at the generated Ru-III species were measured by cyclic voltammetry and UV-vis spectroscopy. The electron transfer shows enantioselectivity. In the case of GO, the bell-shaped pH profile for the ratio k(Lambda)/k(Delta) has a maximum at pH 7 (k(Lambda)/k(Delta) equals 3.4 and 3.9 for 1 and 2, respectively), but its inversion is observed at pH around 5 and 9. The k(Lambda)/k(Delta) ratio equals 2.0 for 2 and GDH at pH 7. The results of theoretical modeling of biological electron transfer for GO using functional docking Monte-Carlo simulations are presented and analyzed together with the experimental observations.
Place, publisher, year, edition, pages
2006. Vol. 41, no 04-mar, 110-116 p.
ruthenium, cyclometalated compounds, X-ray crystallography, glucose oxidase, PQQ glucose dehydrogenase, electron transfer, functional docking Monte-Carlo simulation, cyclometalated ruthenium(ii) complexes, electron-transfer, crystal-structures, peroxidase, mediators, dehydrogenase, resolution, phenylpyridine, catalysis, oxidation
IdentifiersURN: urn:nbn:se:kth:diva-15933DOI: 10.1016/j.molcatb.2006.05.008ISI: 000239932700008ScopusID: 2-s2.0-33746673838OAI: oai:DiVA.org:kth-15933DiVA: diva2:333975
QC 201005252010-08-052010-08-05Bibliographically approved