1dv9

STRUCTURAL CHANGES ACCOMPANYING PH-INDUCED DISSOCIATION OF THE B-LACTOGLOBULIN DIMERSTRUCTURAL CHANGES ACCOMPANYING PH-INDUCED DISSOCIATION OF THE B-LACTOGLOBULIN DIMER

Structural highlights 1dv9 is a 1 chain structure with sequence from Bos taurus. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance. Related: 1bsy, 2blg, 3blg, 1b0o, 1beb, 1bso Resources: FirstGlance, OCA, RCSB, PDBsum Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed We have used NMR spectroscopy to determine the three-dimensional (3D) structure, and to characterize the backbone dynamics, of a recombinant version of bovine beta-lactoglobulin (variant A) at pH 2. 6, where the protein is a monomer. The structure of this low-pH form of beta-lactoglobulin is very similar to that of a subunit within the dimer at pH 6.2. The root-mean-square deviation from the pH 6.2 (crystal) structure, calculated for backbone atoms of residues 6-160, is approximately 1.3 A. Differences arise from the orientation, with respect to the calyx, of the A-B and C-D loops, and of the flanking three-turn alpha-helix. The hydrophobic cavity within the calyx is retained at low pH. The E-F loop (residues 85-90), which moves to occlude the opening of the cavity over the pH range 7.2-6.2, is in the "closed" position at pH 2.6, and the side chain of Glu89 is buried. We also carried out measurements of (15)N T(1)s and T(2)s and (1)H-(15)N heteronuclear NOEs at pH 2.6 and 37 degrees C. Although the residues of the E-F loop (residues 86-89) have the highest crystallographic B-factors, the conformation of this loop is reasonably well defined by the NMR data, and its backbone is not especially mobile on the pico- to nanosecond time scale. Several residues (Ser21, Lys60, Ala67, Leu87, and Glu112) exhibit large ratios of T(1) to T(2), consistent with conformational exchange on a micro- to millisecond time scale. The positions of these residues in the 3D structure of beta-lactoglobulin are consistent with a role in modulating access to the hydrophobic cavity. Structural changes accompanying pH-induced dissociation of the beta-lactoglobulin dimer.,Uhrinova S, Smith MH, Jameson GB, Uhrin D, Sawyer L, Barlow PN Biochemistry. 2000 Apr 4;39(13):3565-74. PMID:10736155 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Beta-lactoglobulin

spinqualitylabelsall models 1dv9, 21 NMR models Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image