Hyperfine-shifted (13)C and (15)N NMR signals from Clostridium pasteurianum rubredoxin: extensive assignments and quantum chemical verification.

ABSTRACT: Stable isotope-labeling methods, coupled with novel techniques for detecting fast-relaxing NMR signals, now permit detailed investigations of paramagnetic centers of metalloproteins. We have utilized these advances to carry out comprehensive assignments of the hyperfine-shifted (13)C and (15)N signals of the rubredoxin from Clostridium pasteurianum (CpRd) in both its oxidized and reduced states. We used residue-specific labeling (by chemical synthesis) and residue-type-selective labeling (by biosynthesis) to assign signals detected by one-dimensional (15)N NMR spectroscopy, to nitrogen atoms near the iron center. We refined and extended these (15)N assignments to the adjacent carbonyl carbons by means of one-dimensional (13)C[(15)N] decoupling difference experiments. We collected paramagne

SUBMITTER: Lin IJ 

PROVIDER: S-EPMC2766250 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature