Expression of doubly labeled Saccharomyces cerevisiae iso-1 ferricytochrome c and 1H,13C and 15N chemical shift assignments by multidimensional NMR

We have expressed [U-C-13,N-15]-labeled Saccharomyces cerevisiae iso-1 cytochrome c C102T;K72A in Escherichia coli with a yield of 11 mg/l of growth medium. Nuclear magnetic resonance (NMR) studies were conducted on the Fe3+ form of the protein. We report herein chemical shift assignments for amide H-1 and N-15, C-13 degrees C-13(alpha) C-13(beta) H-1(alpha) and H-1(beta) resonances based upon a series of three-dimensional NMR experiments: HNCA HN(CO)CA, HNCO, HN(CA)CO, HNCACB, HCA(CO)N, HCCH-TOCSY and HBHA(CBCA)NH, An investigation of the chemical shifts of the threonine residues was also made by using density functional theory in order to help solve discrepancies between N-15 chemical shift assignments reported in this study and those reported previously. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.