Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies of the magnetic field dependence of the magnetic relaxation rate of solvent protons in protein solutions have indicated that this dependence (called relaxation dispersion) is related to the rotational Brownian motion of the solute proteins. In particular, the dispersion of the longitudinal (spin-lattice) relaxation rate 1/T1 shows a monotonic decrease with increasing field, with an inflection point corresponding to a proton Larmor frequency which is inversely proportional to the orientational relaxation time of the protein. We have now compared the relaxation dispersion of solvent 1H, 2H, and 17O In aqueous solutions of lysozyme (molecular weight 14,700) and 1H and 2H in solutions of hemocyanin (molecular weight 14,7 00) and 1H and 2H in solutions of hemocyanin (molecular weight 9 x 10(6)). The main experimental observation is that the dispersion of the relaxation rates of the three solvent nuclei in lysozyme solutions, normalized to their respective rates in pure water, is essentially the same. This is also true for 1H and 2H relaxation in hemocyanin solutions. These results confirm that entire solvent water molecules, rather than exchanging protons, are involved in the interaction. We have been unable to deduce the correct mechanism to explain the data, but we can eliminate several interaction mechanisms from consideration. For example, all observations combined cannot be explained by a simple two-site model of exchange, in which water molecules are either in sites on the protein with a relaxation rate characteristic of these sites, or else in the bulk solvent (the observed relaxation rate being the weighted average of the two). Also eliminated is the class of models in which the protein molecules induce a preferential partial alignment of neighboring solvent molecules, for example by electrostatic interaction of the electric dipole moments of the water with the electric fields produced by surface charges of the protein molecules. In addition, the idea that relaxation of solvent nuclei is due, in the main, to interactions with protein protons is precluded. Rather, it appears that the protein molecules influence the dynamics of the motion of solvent water molecules in their neighborhood in a manner that imposes on all the solvent molecules a correlation time for their orientational relaxation which equals that of the solute proteins.
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PMID:Protein-water interaction studied by solvent 1H, 2H, and 17O magnetic relaxation. 105 81

The absorption of gamma-rays by dilute aqueous solutions of lysozyme and polyinosinic acid (poly I) causes significant increases in the light-scattering power of room temperature solutions in certain critical concentration regions. Light-scattering properties are unaltered by relatively large doses of radiation delivered to heated complexes. Prior irradiation of the poly I alone yields complexes whose light-scattering properties are the same as those of the unirradiated system. Studies of the radiation-induced absorbance changes of these complexes at 260 and 280 nm show behaviour indicative of the radiation chemistry of polynucleotide rather than of lysozyme. From the evidence available, it is postulated that most of the damage is to the poly I rather than lysozyme in the complexes. Increases in light-scattering and dissymmetry are attributed to unwinding of the multi-stranded polynucleotide. The role of water in the formation and radiation sensitivity of the complexes is discussed.
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PMID:Effects of gamma-radiation on the optical properties of aqueous lysozyme-polyinosinic-acid complexes. 107 16

Arthrigenicity of Mycobacterium smegmatis subfractions appeared to be remarkably potentiated in oil vehicles such as squalane or mineral oil, while water-in-oil emulsions containing Arlacel A appeared to decrease or suppress their arthritogenicity. It seems that Arlacel A can exert a suppressive effect on the arthritogenicity of the subfractions. Poly I:C and acetylated wax D potentiated the arthritogenicity of lysozyme-solubilized product, while cord factor was unable to do so. When given together with either cell membrane fraction or cell envelope, the lysozyme-solubilized product produced much more severe disease than that of lysozyme-solubilized product alone. Cell walls lost much of their arthritogenicity when mixed with lysozyme-solubilized product.
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PMID:Arthritogenicity of Mycobacterium smegmatis subfractions, related to different oil vehicle and different composition. 108 57

Infrared absorption spectroscopy has been used to study the effect of organic solvents on the conformation of myoglobin, apomyoglobin, hemoglobin, lysozyme and ribonuclease. Beta structure can easily be induced by specific solvent effects. Films prepared from a 50% (v/v) mixture of alcohol, acetone, pyridine, tetrahydrofuran or dimethylsulfoxide/water mixtures show a high proportion of beta structure. The degree of induction of beta structure depends on the hydrocarbon content of the alcohol in the order methanol greater than ethanol greater than butanol. No beta structure was observed in films prepared from aqueous octanol solutions. Lyophilization tends to decrease secondary structure. The conformation of the proteins depends on the particular solvent system and the solvent composition. Solution studies of myoglobin in pure dimethylsulfoxide show that the conformation is a mixture of random and beta forms while in dimethylsulfoxide/2H2O mixtures the conformation is a mixture of alpha-helical and beta forms.
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PMID:Infrared spectroscopic studies of solvent-induced conformational changes in globular proteins. 114 18

The cell walls from all 21 species of gram-positive bacteria examined, except lysozyme-susceptible Micrococcus lysodeikticus (NCTC 2665) and lysozyme-resistant Staphylococcus epidermidis (ATCC 155), were found to be definitely adjuvant-active in both stimulation of increased serum antibody levels and induction of delayed-type hypersensitivity to ovalbumin when administered to guinea-pigs as water-in-oil emulsions. Using various cell wall lytic enzymes, the immunoadjuvant principles were solubilized with full retention of the adjuvant activities from walls of Staphylococcus aureus (Copenhagen), Streptococcus pyogens (group A, type 6; S43/100), Streptococcus salivarius (IFO 3350), Streptococcus faecalis (IFO 12580), Streptococcus mutans (BHT), Lactobacillus plantarum (ATCC 8014), Bacillus megaterium (IFO 12068), Corynebacterium diphtheriae (Park-Williams No. 8), Mycobacterium smegmatis, and Actinomyces viscous (ATCC 15987). Evidence was obtained that the non-peptidoglycan portion of the cell walls is not essential for manifestation of immunoadjuvancy.
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PMID:Immunoadjuvant activities of cell walls and their water-soluble fractions prepared from various gram-positive bacteria. 118 Aug 72

In the present experimental study the role of lysozyme drops in healing of corneal ulcer of staphylococcal origin (sensitive to chloramphenicol) was studied on 16 albino rabbits. In 8 rabbits, in one eye placibo drops (distilled water) and in the other eye lysozyme 1% were put 4 times daily. In the other 8 rabbits, in one eye chloramphenicol drops 0.4% and in the other eye chloramphenicol drops 0.4% + lysozyme drops 1% were instilled 4 times daily. It was observed that the rate of healing of corneal ulcer was much earlier in the eyes which had local instillation of chloramphenicol drops + lysozyme in comparison to the eyes which had only chloramphenicol drops, lysozyme drops, or distilled water.
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PMID:Lysozyme in corneal ulcer. 120 May 58

An assumption is made on the substantial role of local hydrogen bonds in formation of irregular regions of globular protein polypeptide chains. The statistics of the amino acid composition of irregular regions is examined from this point of view. A statistical analysis of side group-backbone hydrogen bonds is carried out for three proteins: alpha-chy-motrypsin, lysozyme and myoglobin. It is shown that short side groups participate in formation of local hydrogen bonds more often than long ones. Conformations of amino acid residues in the first and the last positions are studied in beta-bends of 9 proteins. It is shown that over 70% of these residues are in conformations corresponding to the formation of local hydrogen bonds of three types: backbone-backbone, side groupbackbone, backbone-water molecule-backbone. Thus, the participation of the cooperative hydrogen-bonding network in stabilization of beta-bends is demonstrated.
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PMID:[The role of local hydrogen bonds in formation of irregular regions of globular protein polypeptide chains]. 121 11

Both alpha zein purified from a commericial preparation and beta zein prepared fresh from corn are soluble in the nonaqueous solvents formamide and dimethylformamide; in this regard zein resembles water soluble proteins such as insulin, ribonuclease, and lysozyme. On the basis of osmotic pressure measurements made in both formamide and dimethylformamide, alpha zein has a number average moleular weight of 21000-24000 daltons and shows no tendency to aggregate or dissociate. Beta zein exists in an aggregated state (dimer and higher forms) in dimethylformamide. Formamide dissociates the beta zein dimer into monomer units but aggregation to higher species occurs with increasing protein concentration.
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PMID:Molecular weight of an extremely hydrophobic protein, zein, in dimethylformamide and in formamide. 126 May 2

A modification that simplifies the spot hybridization technique is described for using biotinylated DNA probes. Plasmid EWD299 having LT gene insert, labelled with biotin either by nick translation or using photobiotin was used as DNA probe for the specific detection of enterotoxigenic Escherichia coli. A simple protocol has been described for easy lysis of test samples by boiling in distilled water followed by detergent treatment and was found to be as efficient as the lysis using lysozyme and protease. Three different solid supports namely DEAE-cellulose paper, nitrocellulose paper and nylon membrane were also compared for their suitability in this spot hybridization test. Nitrocellulose paper was found to give better colour signal with the photobiotinylated DNA probe.
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PMID:Modified spot hybridization test using biotinylated DNA probe. 130 40

Polarization sensitive coherent anti-Stokes Raman scattering (PCARS) spectroscopy is a fruitful technique to study Raman vibrations of diluted molecules under off-electron resonant conditions. We apply PCARS as a direct spectroscopic method to investigate the broad amide I band of proteins in heavy water. In spontaneous Raman spectroscopy, this band is not well resolved. We fit a number of spectra taken of each protein under different polarization conditions, with a single set of parameters. It then appears that some substructure is observed in the amide I band. From this substructure, we determine the percentage of alpha-helix, beta-sheet, and random coil for the proteins lysozyme, albumin, ribonuclease A, and alpha-chymotrypsin.
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PMID:Polarization sensitive coherent anti-Stokes Raman scattering spectroscopy of the amide I band of proteins in solutions. 133 43


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