Differences between the electronic environments of reduced and oxidized Escherichia coli DsbA inferred from heteronuclear magnetic resonance spectroscopy.

DsbA is the strongest protein disulfide oxidant yet known and is involved in catalyzing protein folding in the bacterial periplasm. Its strong oxidizing power has been attributed to the lowered pKa of its reactive active site cysteine and to the difference in thermodynamic stability between the oxidized and the reduced form. However, no structural data are available for the reduced state.

Backbone dynamics of the major coat protein of bacteriophage M13 in detergent micelles by 15N nuclear magnetic resonance relaxation measurements using the model-free approach and reduced spectral density mapping.

The backbone dynamics of the major coat protein (gVIIIp) of the filamentous bacteriophage M13, solubilized in detergent micelles, have been studied using 15N nuclear magnetic resonance spectroscopy at three frequencies. Motional parameters and overall and internal correlation times were derived with the model-free approach. It was also checked whether these parameters had to be modified due to anisotropic motion of the protein/micelle complex.

Backbone dynamics of the 269-residue protease Savinase determined from 15N-NMR relaxation measurements.

Backbone dynamics of Savinase, a subtilisin of 269 residues secreted by Bacillus lentus, have been studied using 15N relaxation measurements derived from proton-detected dimensional 1H-15N-NMR spectroscopy. 15N spin-lattice rate constants (R1), spin-spin relaxation-rate constants(R2), and 1H-15N nuclear Overhauser effects (NOE) were determined for 84% of the backbone amide 15N nuclei. The model-free formalism [Lipari, G.

1H, 13C and 15N NMR backbone assignments and secondary structure of the 269-residue protease subtilisin 309 from Bacillus lentus.

1H, 13C and 15N NMR assignments of the backbone atoms of subtilisin 309, secreted by Bacillus lentus, have been made using heteronuclear 3D NMR techniques. With 269 amino acids, this protein is one of the largest proteins to be sequentially assigned by NMR methods to date. Because of the size of the protein, some useful 3D correlation experiments were too insensitive to be used in the procedure.

Assignment of 1H, 15N, and backbone 13C resonances in detergent-solubilized M13 coat protein via multinuclear multidimensional NMR: a model for the coat protein monomer.

The major coat protein (gVIIIp) of bacteriophage M13 complexed with SDS detergent micelles was used as a model system to study the lipid-bound conformation of the protein. Conditions were found that allowed the recording of good quality of NMR spectra. By making extensive use of three-dimensional heteronuclear (13C, 15N) NMR, we obtained a complete set of resonance assignments for 1HN, 1H alpha, 1H beta, 13C alpha, CO, and 15N and partially assigned the rest of the 1H spectrum.