|Title||Paramagnetic properties of the low- and high-spin states of yeast cytochrome c peroxidase.|
|Publication Type||Journal Article|
|Year of Publication||2013|
|Authors||Vanwetswinkel, S., N. A. J. van Nuland, and A. Volkov|
|Journal||J Biomol NMR|
|Date Published||2013 Sep|
Here we describe paramagnetic NMR analysis of the low- and high-spin forms of yeast cytochrome c peroxidase (CcP), a 34 kDa heme enzyme involved in hydroperoxide reduction in mitochondria. Starting from the assigned NMR spectra of a low-spin CN-bound CcP and using a strategy based on paramagnetic pseudocontact shifts, we have obtained backbone resonance assignments for the diamagnetic, iron-free protein and the high-spin, resting-state enzyme. The derived chemical shifts were further used to determine low- and high-spin magnetic susceptibility tensors and the zero-field splitting constant (D) for the high-spin CcP. The D value indicates that the latter contains a hexacoordinate heme species with a weak field ligand, such as water, in the axial position. Being one of the very few high-spin heme proteins analyzed in this fashion, the resting state CcP expands our knowledge of the heme coordination chemistry in biological systems.
|Alternate Journal||J. Biomol. NMR|