2BT6

Ru(bpy)2(mbpy)-Modified Bovine Adrenodoxin

Summary for 2BT6

• Entry DOI: 10.2210/pdb2bt6/pdb
• Related: 1AYF 1CJE 1E6E 1L6U 1L6V
• Descriptor: ADRENODOXIN 1, FE2/S2 (INORGANIC) CLUSTER, (4'-METHYL-2,2'BIPYRIDINE)BIS(2,2'-BIPYRIDINE), ... (5 entities in total)
• Functional Keywords: ruthenium(ii) bipyridyl complex, intramolecular electron transfer, electron transport, metal-binding
• Biological source: BOS TAURUS (BOVINE)
• Cellular location: Mitochondrion matrix: P00257
• Total number of polymer chains: 2
• Total formula weight: 25268.44

Authors

Halavaty, A.,Mueller, J.J.,Contzen, J.,Jung, C.,Hannemann, F.,Bernhardt, R.,Galander, M.,Lendzian, F.,Heinemann, U. (deposition date: 2005-05-26, release date: 2006-01-25, Last modification date: 2024-11-06)

Primary citation

Halavaty, A.,Mueller, J.J.,Contzen, J.,Jung, C.,Hannemann, F.,Bernhardt, R.,Galander, M.,Lendzian, F.,Heinemann, U.
Light-Induced Reduction of Bovine Adrenodoxin Via the Covalently Bound Ruthenium(II) Bipyridyl Complex: Intramolecular Electron Transfer and Crystal Structure.
Biochemistry, 45:709-, 2006

PubMed Abstract: Bovine adrenodoxin (Adx) plays an important role in the electron-transfer process in the mitochondrial steroid hydroxylase system of the bovine adrenal cortex. Using electron paramagnetic resonance (EPR) spectroscopy, we showed that photoreduction of the [2Fe-2S] cluster of Adx via (4'-methyl-2,2'-bipyridine)bis(2,2'-bipyridine)ruthenium(II) [Ru(bpy)2(mbpy)] covalently attached to the protein surface can be used as a new approach to probe the "shuttle" hypothesis for the electron transfer by Adx. The 1.5 A resolution crystal structure of a 1:1 Ru(bpy)2(mbpy)-Adx(1-108) complex reveals the site of modification, Cys95, and allows to predict the possible intramolecular electron-transfer pathways within the complex. Photoreduction of uncoupled Adx, mutant Adx(1-108), and Ru(bpy)2(mbpy)-Adx(1-108) using safranin T as the mediating electron donor suggests that two electrons are transferred from the dye to Adx. The intramolecular photoreduction rate constant for the ruthenated Adx has been determined and is discussed according to the predicted pathways.

PubMed: 16411746
DOI: 10.1021/BI0510330

Experimental method

X-RAY DIFFRACTION (1.5 Å)