Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The dark and light reduction of nitrate and nitrite by cell-free preparations of the blue-green alga Anacystis nidulans has been investigated. The three following methods have been successfully applied to the preparation of active particulate fractions from the alga cells: (a) shaking with glass beads, (b) lysozyme treatment and lysis of the resulting protoplasts, and (c) sonication. The two enzymes of the nitrate-reducing system-namely, nitrate reductase and nitrite reductase-are firmly bound to the isolated pigment-containing particles, and can be easily solubilized by prolonging the vibration or sonication time. Both enzymes-whether solubilized or bound to the particles-depend on reduced ferredoxin as the immediate electron donor. In its presence, the alga particles catalyze the gradual photoreduction of nitrate to nitrite and ammonia, a process that can thus be considered as one of the most simple and relevant examples of Photosynthesis. Some of the properties of nitrate reductase have been studied. Nitrate reductase as well as nitrite reductase are adaptive enzymes repressed by ammonia.
Mol Cell Biochem 1976 Feb 25
PMID:Ferredoxin-dependent photosynthetic reduction of nitrate and nitrite by particles of Anacystis nidulans. 0 27

The alterations of tryptophan fluorescence parametres with pH may be due to: 1) conformational changes; 2) changes in the ionic state of groups capable of quenching the tryptophan fluorescence. The applications of the model of discrete forms of tryptophan allow one to separate these mechanisms and estimate the middle points of conformational changes and pK's of quenching groups. For chymotrypsin (CT) and chymotrypsinogen (CTG) conformational changes were registrated with middle points: CT pH 4.1 and 8.8; CTG -- pH 3.2 and 9.8, and pK's of histidines: CT -- 5.4 and 6.6; CTG -- 5.6 and 7.0. For trypsin conformational changes were shown with middle points: pH 3.2; 5.8; 8.5 and for lysozyme -- pH 5.9.
Mol Biol (Mosk)
PMID:[pH-dependence of fluorescence parameters of chymotrypsin, chymotrypsinogen, trypsin and lysozyme]. 3 49

Sedimentation method has been used to study hen egg-white lysozyme binding to glucosylated (from T2 phage) and non-glucosylated (from calf thymus) DNA under conditions similar to physiological ones (pH 7,3--7,4, ionic strength 0.07--0.24). The results indicate that lysozyme binds cooperatively to both DNA's. Binding parameters have been obtained by applying the theory of one-dimensional adsorption of small molecules on a linear homopolymer. X-ray patterns of complexes with different protein content have been obtained.
Mol Biol (Mosk)
PMID:[DNA complexes with lysozyme]. 3 32

The previously described temperature and pH-dependent transition in the solid state of hen lysozyme was studied in solution. Experiment concerning the velocity of lysis of M. luteus by lysozyme and its behavior in presence of an inhibitor (GlcNAc) as well as a reinvestigation of the Arrhenius curves over a large range of pH, demonstrated the existence of two temperature-induced domains. An inhibitor-insensitive lysozyme form was characterized at 40 degrees (physiological temperature).
Mol Biol Rep 1979 Aug 31
PMID:The temperature and pH-dependent transition of hen lysozyme. Characterization of two temperature-defined domains and of an N-acetylglucosamine (inhibitor)-insensitive form. 4 Jan 9

Ultrastructural and immunohistologic findings in a nodular variant of Hodgkin's disease with lymphocytic predominance, called nodular paragranuloma, are presented and compared with those in so-called progressively transformed germinal centers. These are large follicles with numerous lymphocytes which can be found not only in nonspecific lymphadenitis, but also in lymph nodes from patients with nodular paragranuloma. The immunoperoxidase technique was applied on paraffin sections to detect intracytoplasmic immunoglobulin and lysozyme. The so-called L & H type Sternberg-Reed cells contained IgG and one type of light chain per cell, suggesting that such cells produce immunoglobulin. The ultrastructure of the L & H type Sternberg-Reed cells favored the immunoblastic nature of these cells. It is concluded that nodular paragranuloma differs from other types of Hodgkin's disease by its localization in B-cell areas and the presence of atypical B immunoblasts.
Virchows Arch B Cell Pathol Incl Mol Pathol 1979
PMID:Nodular paragranuloma and progressively transformed germinal centers. Ultrastructural and immunohistologic findings. 4 15

Under experimental conditions of genetic transformation, protamine and total histone were bactericidal for Bacillus subtilis cells. The abilities to cause lethality were very similar for both, either protamine or histone, with no antagonistic effects amongst these natural polycations. With both basic proteins acting simultaneously the enhancement was higher than a summation of the separate lethal effects. Sublethal concentration of protamine added at the beginning of transformation time, produced a strong inhibition of transforming efficiency. The same concentration added later than 10 min from the start of transformation had no inhibitory effect. These facts together with the absence of inhibition by simple pretreatment of DNA alone as well as the cell protection by protamine against lytic activity of lysozyme, suggest a protamine-cell surface interaction which impedes DNA uptake events.
Mol Gen Genet 1979 Mar 05
PMID:Lethal effect of protamine and histone on competent Bacillus subtilis cells. Inhibition of genetic transformation by protamine in sublethal concentration. 11 Oct 2

The protein spin-echo decay and recovery of longitudinal magnetization were studied in seven globular proteins: cytochrome C, ribonuclease, lysozyme, DNA, hemoglobin, serum albumin and gamma-globulin in D2O solutions. For comparison the Tobacco mosaic virus (TMV) protons in D2O solutions were also investigated. The spin-echo decay of all 7 proteins can be separated into three components: a slowly decaying component with an amplitude of about 10% of the amplitude of the total signal, intermediately and fastly decaying components, the two latter being comparable in amplitudes. Longitudinal relaxation is more simple in character. The value of T2 of the protons responsible for the fastly decaying components in linearly dependent on the molecular weight of the protein, a fact indicating that the regions of the proteins with a "rigid" structure can be responsible for this component. The intermediate component, whose contribution increases with temperature, was ascribed to the mobile regions of the protein, and the slowly decaying component to the mobile protein side chains. Weak dependence of T1 on the protein molecular weight and some other obtained data give additional evidence for the presence of motion within macromolecules. The peculiarities of this motion is in good correspondence with the notion about the existence of the segmental motion of the polypeptide chain (conformational mobility of the protein). In contrast to proteins the spin-echo decay of TMV lacked the slow component and the "solid" echo signal was observed which indicates the existence of a "rigid" structure in the macromolecules of the virus.
Mol Biol (Mosk)
PMID:[Study of the conformational mobility of globular proteins by pulse methods of NMR]. 20 75

A method for investigating the microstruct and dynamics of biological systems by means of triplet-excited molecules is suggested. The method is based on the phenomenon of triplet excitation disactivation by exchange-resonance triplet-triplet energy transfer to the acceptor or by intercombination conversion induced by interaction of an excited molecule with a paramagnetic center. The disactivation efficiency was measured by registrating the phosphorescense decay kinetics. The interaction of the triplet label eosin isothiocyanate, covalently coupled with albumine, lysozyme, sarcoplasmic reticulum membrane and Ca-Mg-dependent sarcoplasmic reticulum ATPase, with O2, the stable nitroxide radicals and ions of Mn2+ was investigated to analyse the potentialities of this method. As a model system the eosin phosphorescence quenching by the same quenchers in glycerine-aguaous solutions was studied. The method permits to investigate the microviscosity and microstructure of biological objects in the label attached region on interaction of the label with a sound-quencher with constants being 10(4) divided by 10(9) M-1 sec-1 and to measure the lateral diffusion of molecules in highly viscosity media (10 divided by 10(5) santypuas).
Mol Biol (Mosk)
PMID:[Investigation of the microstructure of biological systems by triplet label]. 22 37

A method is proposed that permits the structural similarity between any pair of proteins to be analyzed in a completely general manner. In the proposed procedure, all possible structural segments of a given length from one protein are compared with all possible segments from the other protein. This set of comparisons reveals any structural similarities between the two proteins being compared, and also provides a basis for estimating the probability that a particular degree of structural homology could have occurred by chance. Application of the method to the comparison of T4 bacteriophage lysozyme and carp calcium-binding protein suggests that the previously reported structural similarity between parts of these two proteins [Tufty, R. M.& Kretsinger, R. H. (1975) Science 187, 167-169] is no better than would be expected by chance. On the other hand, the structural correspondence between phage lysozyme and hen egg-white lysozyme [Rossman, M.G. & Argos, P. (1976) J. Mol. Biol. 105, 75-96] does appear to be significant.
 ...
PMID:A general method to assess similarity of protein structures, with applications to T4 bacteriophage lysozyme. 27 59

The electronic-conformational interactions (ECI) of enzyme-substrate complexes are treated with the help of the method of intermolecular orbitals. The applicability of this approach is shown concerning some problems, related to ECI. The activation of N2 in the active site of nitrogenase, the proton transfer in the system, containing hydrogen bonds, and the modelling of the initial state of the reaction of lysozyme with oligosaccharides were examined.
Mol Biol (Mosk)
PMID:[Electronic-conformational interactions of molecular-biological systems. II. Study of the enzyme-substrate complex with the help of qualitative methods of quantum chemistry]. 46 Jan 99


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