A SYSTEMATIC-APPROACH TOWARDS THE COMPLETE ASSIGNMENT OF C-13 RESONANCES FOR HORSE FERROCYTOCHROME-C

The complete H-1-NMR assignments for horse ferrocytochrome c have been reported by Wand and colleagues and by our group at Oxford. Using these H-1 assignments, we now report chemical shift assignment for 205 C-13 resonances arising from horse ferrocytochrome c. This is from a total of 437 C-13 nuclei with covalently attached protons. These chemical shift assignments have been achieved using H-1-detected two-dimensional heteronuclear H-1-C-13 correlation techniques. The data have been collected from samples of horse ferrocytochrome c without isotopic enrichment. The complete C-13 assignments for all carbons with covalently linked protons are reported for the amino acids Ala, Thr, Val and Gly. Specific assignments are tabulated for all 49 methyl groups, for 52 of 92 alpha-carbon resonances, for 10 resonances associated with the group, for all aromatic side-chain C-13 resonances which have covalent protons and give rise to observable cross peaks under the experimental conditions used, as well as for a number of other side chains of aliphatic amino acids.