Efficient Encounter Complex Formation and Electron Transfer to Cytochrome c Peroxidase with an Additional, Distant Electrostatic Binding Site

Angewandte Chemie International Edition, vol. 59, pp. 23239–23243

Abstract

Electrostatic interactions can strongly increase the efficiency of protein complex formation. The charge distribution in redox proteins is often optimized to steer a redox partner to the electron transfer active binding site. To test whether the optimized distribution is more important than the strength of the electrostatic interactions, an additional negative patch was introduced on the surface of cytochrome c peroxidase, away from the stereospecific binding site, and its effect on the encounter complex as well as the rate of complex formation was determined. Monte Carlo simulations and paramagnetic relaxation enhancement NMR experiments indicate that the partner, cytochrome c, interacts with the new patch. Unexpectedly, the rate of the active complex formation was not reduced, but rather slightly increased. The findings support the idea that for efficient protein complex formation the strength of the electrostatic interaction is more critical than an optimized charge distribution.

Authors 7

1. Antonella Di Savino Aachen

   Leiden University

   Affiliation as printed

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

2. Johannes M. Foerster

   University of Bayreuth

   Affiliation as printed

   University of Bayreuth Computational Biochemistry Universitätsstraße 30, NW I 95447 Bayreuth Germany

3. Thijmen La Haye Aachen

   Leiden University

   Affiliation as printed

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Present address: University of Delft TNW Applied Sciences Van der Maasweg 9 2629 HZ Delft The Netherlands

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Present address: University of Delft TNW Applied Sciences Van der Maasweg 9 2629 HZ Delft The Netherlands

4. Anneloes J. Blok Aachen

   Leiden University

   Affiliation as printed

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

5. Monika Timmer Aachen

   Leiden University

   Affiliation as printed

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

6. G. Matthias Ullmann

   University of Bayreuth

   Affiliation as printed

   University of Bayreuth Computational Biochemistry Universitätsstraße 30, NW I 95447 Bayreuth Germany

7. Marcellus Ubbink corresponding Aachen

   Leiden University

   Affiliation as printed

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands

   Leiden University Institute of Chemistry Einsteinweg 55 2333 CC Leiden Netherlands