Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P11684 (Uteroglobin)
 114 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

One of the monoclinic P21 forms of uteroglobin, a progesterone-binding protein secreted by the rabbit uterus, was crystallized and subjected to X-ray diffraction analysis at 1.64 A resolution. The analysis was refined to an R factor of 0.19 and the 1096 non-hydrogen atomic positions are known to an accuracy of about 0.18 A. The average isotropic temperature factor B was 10.4 A2. Uteroglobin is a dimer of two independent polypeptide chains of 70 residues linked by two disulfide bridges and related by a pseudo binary axis. Each monomer is folded into four alpha-helices. An oblong hydrophobic pocket is observed inside the dimer, and the possibility that it represents a progesterone-binding site is discussed. The present model includes 165 possible sites for water molecules, of which six are located in the hydrophobic pocket. Polar groups are involved in hydrogen bonding (intramolecular, intermolecular or with water molecules).
 ...
PMID:Structure and refinement of the oxidized P21 form of uteroglobin at 1.64 A resolution. 270 39

The structure of uteroglobin, a progesterone binding protein from rabbit uterine fluid, was determined and refined at 1.34 A resolution to a conventional R-factor of 0.229. The accuracy of the co-ordinates is estimated to be 0.15 A. The isotropic temperature factor of individual atoms was refined and its average value is 11.9 A2 for the 548 non-hydrogen atoms of the protein monomer. A total of 83 water molecules was located in difference electron density maps and refined, first using a constant occupancy factor of 1 and then variable occupancy, the final (Q) being 0.63. The mean temperature factor of the water oxygen atoms is 26.4 A2. Uteroglobin is a dimer and its secondary structure consists of four alpha-helices per monomer that align in an anti-parallel fashion. There is one beta-turn between helix 2 and helix 3 (Lys26 to Glu29); 76% of the residues are part of the alpha-helices. In the core of the dimeric protein molecule, between the two monomers that are held together by two disulfide bridges, we have observed a closed cavity. Its length is 15.6 A and its width is 9 A; 14 water molecules could be positioned inside. In the "bottom" part of the protein, near the C terminus, we have observed a smaller cavity, occupied by two water molecules. The calculation of the molecular surface revealed four surface pockets whose possible functional implications are discussed below.
 ...
PMID:Refinement of the C222(1) crystal form of oxidized uteroglobin at 1.34 A resolution. 365 5

An efficient molecular simulation methodology has been developed to determine the positioning of water molecules in the binding site of a protein or protein-ligand complex. Occupancies and absolute binding free energies of water molecules are computed using a statistical thermodynamics approach. The methodology, referred to as Just Add Water Molecules (JAWS), features "theta-water" molecules that can appear and disappear on a binding-site grid. Key approximations render the technique far more efficient than conventional free energy simulations. Testing of JAWS on five diverse examples (neuraminidase, scytalone dehydratase, major urinary protein 1, beta-lactoglobulin, and COX-2) demonstrates its accuracy in locating hydration sites in comparison to results from high-resolution crystal structures. Possible applications include aid in refinement of protein crystal structures, drug lead optimization, setup of docking calculations, and simulations of protein-ligand complexes.
 ...
PMID:Prediction of the water content in protein binding sites. 1975 86