Solution NMR study of the yeast cytochrome c peroxidase: cytochrome c interaction.

TitleSolution NMR study of the yeast cytochrome c peroxidase: cytochrome c interaction.
Publication TypeJournal Article
Year of Publication2013
AuthorsVolkov, A., and N. A. J. van Nuland
JournalJ Biomol NMR
Date Published2013 Jul
KeywordsAlgorithms, Cytochrome-c Peroxidase, Cytochromes c, Kinetics, Models, Molecular, Molecular Conformation, Nuclear Magnetic Resonance, Biomolecular, Protein Binding

Here we present a solution NMR study of the complex between yeast cytochrome c (Cc) and cytochrome c peroxidase (CcP), a paradigm for understanding the biological electron transfer. Performed for the first time, the CcP-observed heteronuclear NMR experiments were used to probe the Cc binding in solution. Combining the Cc- and CcP-detected experiments, the binding interface on both proteins was mapped out, confirming that the X-ray structure of the complex is maintained in solution. Using NMR titrations and chemical shift perturbation analysis, we show that the interaction is independent of the CcP spin-state and is only weakly affected by the Cc redox state. Based on these findings, we argue that the complex of the ferrous Cc and the cyanide-bound CcP is a good mimic of the catalytically-active Cc-CcP compound I species. Finally, no chemical shift perturbations due to the Cc binding at the low-affinity CcP site were observed at low ionic strength. We discuss possible reasons for the absence of the effects and outline future research directions.

Alternate JournalJ. Biomol. NMR
PubMed ID23708935