Backbone dynamics of plastocyanin in both oxidation states. Solution structure of the reduced form and comparison with the oxidized state.Bertini, I., Bryant, D.A., Ciurli, S., Dikiy, A., Fernandez, C.O., Luchinat, C., Safarov, N., Vila, A.J., Zhao, J.
(2001) J.Biol.Chem. 276: 47217-47226
- PubMed: 11509552
- DOI: 10.1074/jbc.M100304200
- Primary Citation of Related Structures:
- PubMed Abstract:
- THE FIRST SOLUTION STRUCTURE OF A PARAMAGNETIC COPPER(II) PROTEIN: THE CASE OF OXIDIZED PLASTOCYANIN FROM THE CYANOBACTERIUM Synechocystis PCC6803
BERTINI, I.,CIURLI, S.,DIKIY, A.,FERNANDEZ, C.O.,LUCHINAT, C.,SAFAROV, N.,SHUMILIN, S.,VILA, A.J.
(2001) J.Am.Chem.Soc. 123: 2405
A model-free analysis based on (15)N R(1), (15)N R(2), and (15)N-(1)H nuclear Overhauser effects was performed on reduced (diamagnetic) and oxidized (paramagnetic) forms of plastocyanin from Synechocystis sp. PCC6803. The protein backbone is rigid, d ...
A model-free analysis based on (15)N R(1), (15)N R(2), and (15)N-(1)H nuclear Overhauser effects was performed on reduced (diamagnetic) and oxidized (paramagnetic) forms of plastocyanin from Synechocystis sp. PCC6803. The protein backbone is rigid, displaying a small degree of mobility in the sub-nanosecond time scale. The loops surrounding the copper ion, involved in physiological electron transfer, feature a higher extent of flexibility in the longer time scale in both redox states, as measured from D(2)O exchange of amide protons and from NH-H(2)O saturation transfer experiments. In contrast to the situation for other electron transfer proteins, no significant difference in the dynamic properties is found between the two redox forms. A solution structure was also determined for the reduced plastocyanin and compared with the solution structure of the oxidized form in order to assess possible structural changes related to the copper ion redox state. Within the attained resolution, the structure of the reduced plastocyanin is indistinguishable from that of the oxidized form, even though small chemical shift differences are observed. The present characterization provides information on both the structural and dynamic behavior of blue copper proteins in solution that is useful to understand further the role(s) of protein dynamics in electron transfer processes.
Magnetic Resonance Center and Department of Chemistry, University of Florence, Via L. Sacconi, 6-50019 Sesto Fiorentino, Italy.