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Journal Issue - Volume 1 Issue 1 (January 1992)

  • Why Protein Science ?

  • Hans Neurath
  • Published in Wiley Interscience on Dec 31, 2008
  • DOI: 10.1002/pro.5560010101 (p 1-2)

Abstract A “kinemage” (kinetic image) is a scientific illustration presented as an interactive computer display. Operations on the displayed kinemage respond within a fraction of a second: the entire image can be rotated in real time, parts of the display can be turned on or off, points can be identified by selecting them, and the change between different forms can be animated. A kinemage is prepared and specified by the author(s)...

Abstract Amide proton exchange of thioredoxin is used to monitor the structural effects of reduction of its single disulfide. An effective 3–5‐proton difference between the oxidized and reduced protein form is observed early in proton out‐exchange of the whole protein, which is independent of temperature in the range of 5–45 °C, indicating that redox‐sensitive changes are probably not due to low‐energy structural fluctuations....

Abstract The partial specific volume and adiabatic compressibility were determined at several temperatures for oxidized and reduced Escherichia coli thioredoxin. Oxidized thioredoxin had a partial specific volume of 0.785–0.809 mL/g at the observed upper limit for all proteins whereas the partial specific volume of reduced thioredoxin was 0.745–0.755 mL/g, a value in the range found for a majority of proteins. The adiabatic...

Abstract An important step in understanding how a protein folds is to determine those regions of the sequence that are critical to both its stability and its folding pathway. We chose phosphoribosyl anthranilate isomerase from Escherichia coli, which is a monomeric representative of the (βα)8 barrel family of proteins, to construct a variant that carries an internal tandem duplication of the fifth βα module. This (βα)9 variant was enzymically active and...

Abstract The engineered disulfide bridge between residues 21 and 142 of phage T4 lysozyme spans the active‐site cleft and can be used as a switch to control the activity of the enzyme (Matsumura, M. & Matthews, B.W., 1989, Science 243, 792–794). In the oxidized form the disulfide increases the melting temperature of the protein by 11 °C at pH 2. The crystal structure of this mutant lysozyme has been determined in both...

Abstract We have developed a method for the covalent immobilization of peptides, for the purpose of C‐terminal sequencing, to a novel solid support, carboxylic acid‐modified polyethylene (PE‐COOH) film. The peptides are attached by coupling the N‐terminal amino group to the activated carboxyl groups of the film. Reagents for carboxyl group activation, including 1,3‐dicyclohexylcarbodiimide (DCC), 1,1′‐carbonyldiimidazole (CDI),...

Abstract Proteins and peptides can be sequenced from the carboxy‐terminus with isothiocyanate reagents to produce amino acid thiohydantoin derivatives. Previous studies in our laboratory have focused on solution phase conditions for formation of the peptidylthiohydantoins with trimethylsilylisothiocyanate (TMS‐ITC) and for hydrolysis of these peptidylthiohydantoins into an amino acid thiohydantoin derivative and a new shortened...

Abstract The three‐dimensional structure of the first epidermal growth factor (EGF)‐like module from human factor IX has been determined in solution using two‐dimensional nuclear magnetic resonance (in the absence of calcium and at pH 4.5). The structure was found to resemble closely that of EGF and the homologous transforming growth factor‐α (TGF‐α). Residues 60–65 form an antiparallel β‐sheet with residues 68–73. In the C‐terminal subdomain a...

Abstract Structural perturbations due to a series of mutations at the 30–51 disulfide bond of bovine pancreatic trypsin inhibitor have been explored using NMR. The mutants replaced cysteines at positions 30 and 51 by alanine at position 51 and alanine, threonine, or valine at position 30. Chemical shift changes occur in residues proximate to the site of mutation. NOE assignments were made using an automated procedure, NASIGN, which...

Abstract Primary amines functionally replace lysine 258 by catalyzing both the 1,3‐prototropic shift and external aldimine hydrolysis reactions with the inactive aspartate aminotransferase mutant K258A. This finding allows classical Brønsted analyses of proton transfer reactions to be applied to enzyme‐catalyzed reactions. An earlier study of the reaction of K258A with cysteine sulfinate (Toney, M.D. & Kirsch, J.F., 1989,...

Abstract The role of carbohydrate chains for the structure, function, stability, and folding of glycoproteins has been investigated using invertase as a model. The protein is encoded by several different genes, and its carbohydrate moiety is heterogeneous. Both properties complicate physicochemical comparisons. Here we used the temperature‐sensitive sec18 secretion mutant of yeast with a single invertase gene (SUC2). This mutant...

Abstract The bifunctional reagent N‐(4‐azidobenzoyl)‐putrescine was synthesized and covalently bound to rabbit skeletal muscle actin. The incorporation was mediated by guinea pig liver transglutaminase under conditions similar to those described by Takashi (1988, Biochemistry 27, 938–943); up to 0.5 M/M were incorporated into G‐actin, whereas F‐actin was refractory to incorporation. Peptide fractionation showed that at least 90% of the label...

Abstract Models for the structure of the fibers of deoxy sickle cell hemoglobin (Hb S, β6 Glu → Val) have been obtained from X‐ray and electron microscopic studies. Recent molecular dynamics calculations of polymer formation give new insights on the various specific interactions between monomers. Site‐directed mutagenesis with expression of the Hb S β subunits in Escherichia coli provides the experimental tools to test these models. For Hb S,...

Abstract The histidine‐glycine‐rich region of the light chain of cleaved high molecular weight kininogen (HK) is thought to be responsible for binding to negatively charged surfaces and initiation of the intrinsic coagulation, fibrinolytic, and kinin‐forming systems. However, the specifically required amino acid sequences have not been delineated. An IgG fraction of a monoclonal antibody (MAb) C11C1 to the HK light chain was shown...

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