2gi9
Backbone Conformational Constraints in a Microcrystalline U-15N-Labeled Protein by 3D Dipolar-Shift Solid-State NMR Spectroscopy
OverviewOverview
Structural studies of uniformly labeled proteins by magic-angle spinning NMR spectroscopy have rapidly matured in recent years. Site-specific chemical shifts of several proteins have been assigned and structures determined from 2D or 3D data sets containing internuclear distance information. Here we demonstrate the application of a complementary technique for constraining protein backbone geometry using a site-resolved 3D dipolar-shift pulse sequence. The dipolar line shapes report on the relative orientations of 1H-15N[i] to 1H-15N[i+1] dipole vectors, constraining the torsion angles phi[i] and psi[i]. In addition, from the same 3D data set, several 1H-15N[i] to1H-15N[i+2] line shapes are extracted to constrain the torsion angles phi[i], psi[i], phi[i+1], and psi[i+1]. We report results for the majority of sites in the 56-residue beta1 immunoglobulin binding domain of protein G (GB1), using 3D experiments at 600 MHz 1H frequency. Excellent agreement between the SSNMR results and a new 1.14 A crystal structure illustrate the general potential of this technique for high-resolution structural refinement of solid proteins.
About this StructureAbout this Structure
2GI9 is a Single protein structure of sequence from Staphylococcus aureus. Full crystallographic information is available from OCA.
ReferenceReference
Backbone conformational constraints in a microcrystalline U-15N-labeled protein by 3D dipolar-shift solid-state NMR spectroscopy., Franks WT, Wylie BJ, Stellfox SA, Rienstra CM, J Am Chem Soc. 2006 Mar 15;128(10):3154-5. PMID:16522090 Page seeded by OCA on Sun May 4 05:08:11 2008