Work

Complete 15 N and 1 H NMR assignments for the amino-terminal domain of the phage 434 repressor in the urea-unfolded form

Year: 1992

Type: article

Abstract: The amino-terminal domain of the phage 434 repressor consisting of residues 1-69 forms a globular structure of five tightly packed helices, with nearly identical molecular architectures in crystals and in solution. Upon addition of urea to an aqueous solution of this protein, the NMR spectrum of a second form of the protein appears in addition to the native form, and at a urea concentration of 7 M, this urea-unfolded form is the only species observed. At intermediate urea concentrations, the two forms of the protein inter-convert at a rate that allows the observation of the exchange process by NMR. Starting from the previous assignments for the native protein, we obtained nearly complete sequence-specific (1)H and (15)N NMR assignments for the unfolded form of the protein. For most amino acid residues, the (1)H chemical shifts of the urea-unfolded protein are very similar to the random coil values, but some discrete regions of the polypeptide chain were identified that are likely to retain residual nonrandom spatial structure as evidenced by deviations of (1)H chemical shifts and amide proton exchange rates from the expected random coil values.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.89.10.4397

Authors: Dario Neri, Gerhard Wider, Kurt Wüthrich

Institutions: ETH Zurich, Institute of Molecular Biology and Biophysics

Language: English

Topic: Protein Structure and Dynamics

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: bronze

Funder: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung

Award: Anwendung und Weiterentwicklung der NMR-Methode zur Protein- strukturermittlung