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1.

001-es BibID:	BIBFORM005964
Első szerző:	Aszalos Adorján
Cím:	Depolymerization of microtubules alters membrane potential and affects the motional freedom of membrane proteins / Adorjan Aszalos, Sandor Damjanovich, Michael M. Gottesman
Dátum:	1986
Megjegyzések:	Two independent lines of evidence were obtained indicating that microtubule depolymerization affects the functions and the physical state of membranes in intact Chinese hamster ovary cells. The first type of evidence was obtained by using the dye dihexyloxacarbocyanine iodide to measure membrane potential before and after treatment with several microtubule active agents. Microtubule depolymerization resulted in a decrease in cell fluorescence, whereas stabilization of microtubules with taxol resulted in an increase in cell fluorescence. These effects of the drugs were due to their interactions with microtubules and not to direct effects of the drugs on the plasma membranes for the following reasons: effects were time dependent and required entry into the cells as indicated by the lack of fluorescence change in a multi-drug-resistant mutant that does not accumulate antimicrotubule drugs and a colcemid-resistant tubulin mutant did not show these effects on cell fluorescence. Evidence for altered motional freedom of membrane proteins in the plasma membrane was obtained by using electron spin resonance analysis of maleimide spin probe labeled cells. This study showed that depolymerization of microtubules results in increased motional freedom of maleimide-labeled sulfhydryl group containing proteins. Taken together, these data argue that microtubules function in mammalian cells to regulate the physical state of membranes and modulate membrane potential generated across cell membranes.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban analysis Animal Cell Line Cell Membrane Cricetulus Electron Spin Resonance Spectroscopy Female Fluorescence Hamsters Kinetics Membrane Potentials Membrane Proteins metabolism methods Microtubules Ovary physiology ultrastructure
Megjelenés:	Biochemistry. - 25 : 19 (1986), p. 5804-5809. -
További szerzők:	Damjanovich Sándor (1936-2017) (biofizikus) Gottesman, Michael M.
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2.

001-es BibID:	BIBFORM006025
Első szerző:	Balázs Margit (sejtbiológus, molekuláris genetikus)
Cím:	Fluorescent tetradecanoylphorbol acetate : a novel probe of phorbol ester binding domains / Balázs, M., Szöllösi, J., Lee, W. C., Haugland, R. P., Guzikowski, A. P., Fulwyler, M. J., Damjanovich, S., Feuerstein, B. G., Pershadsingh, H. A.
Dátum:	1991
Megjegyzések:	Protein kinase C (PKC) has a prominent role in signal transduction of many bioactive substances. We synthesized the fluorescent derivative, phorbol-13-acetate-12-N-methyl-N-4-(N,N'-di(2-hydroxyethyl)amino)-7-n itr obenz-2-oxa-1,3-diazole-aminododecanoate (N-C12-Ac(13)) of 12-O-tetradecanoylphorbol-13-acetate (TPA) to monitor the location of phorbol ester binding sites and evaluate its potential use as a probe of PKC in viable cells. The excitation maximum wavelength of N-C12-Ac(13) is close to 488 nm, facilitating its use in argon-ion laser flow and imaging cytometry. When incubated with 100 nM N-C12-Ac(13) at 25 degrees C, P3HR-1 Burkitt lymphoma cells accumulated the dye rapidly, reaching maximum fluorescence within 25 min, 20-fold above autofluorescence. Addition of unlabeled TPA significantly decreased the fluorescence of N-C12-Ac(13) stained cells in a dose-dependent manner indicating specific displacement of the bound fluoroprobe. Competitive displacement of [3H]-phorbol-12,13-dibutyrate ([3H]-PBu2) from rat brain cytosol with N-C12-Ac(13) gave an apparent dissociation constant (Kd) of 11 nM. N-C12-Ac(13) possessed biological activity similar to TPA. Like TPA (final concentration 65 nM) N-C12-Ac(13), at a lower concentration (51 nM), induced expression of Epstein-Barr viral glycoprotein in P3HR-1 cells, differentiation of promyelocytic HL60 cells, and caused predicted changes in the mitotic cycle of histiocytic DD cells. Microspectrofluorometric images of single cells labeled with N-C12-Ac(13) showed bright fluorescence localized intracellularly and dim fluorescence in the nuclear region, consistent with dye binding mainly to cytoplasmic structures and/or organelles and being mostly excluded from the nucleus. Because of the high level of non-specific binding of N-C12-Ac(13), this probe is not ideal for visualizing PKC in intact cells, but would be a valuable fluoroprobe to investigate the kinetic properties of purified PKC. Also, knowledge gained from these studies allows us to predict structures of fluorescent phorbols likely to have less non-specific binding and, consequently, be potentially useful for monitoring PKC in viable cells.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban analysis Animal Antigens,Viral Binding Sites Brain Chemistry Cell Cycle chemical synthesis Cytosol Dyes Female Flow Cytometry Fluorescence Fluorescence Polarization Fluorescent Dyes Gene Expression Herpesvirus 4,Human Image Processing,Computer-Assisted immunology metabolism Oxadiazoles pharmacology Phorbol Esters Protein Kinase C Rats Rats,Inbred Strains Signal Transduction Support,Non-U.S.Gov't Support,U.S.Gov't,P.H.S. Tetradecanoylphorbol Acetate Tumor Cells,Cultured
Megjelenés:	Journal of Cellular Biochemistry. - 46 : 3 (1991), p. 266-276. -
További szerzők:	Szöllősi János (1953-) (biofizikus) Lee, W. C. Haugland, R. P. Guzikowski, A. P. Fulwyler, Mack J. Damjanovich Sándor (1936-2017) (biofizikus) Feuerstein, Burt G. Pershadsingh, Harrihar A.
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3.

001-es BibID:	BIBFORM005936
Első szerző:	Damjanovich Sándor (biofizikus)
Cím:	The role of the allosteric sites in the x-ray inactivation of phosphorylase b / Damjanovich, S., Sanner, T., Pihl, A.
Dátum:	1967
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Binding Sites Chloromercuribenzoates Glucosyltransferases pharmacology Phosphorylase b radiation effects Sulfhydryl Compounds
Megjelenés:	European Journal of Biochemistry. - 1 : 3 (1967), p. 347-352. -
További szerzők:	Sanner, Tore Pihl, Alexander
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4.

001-es BibID:	BIBFORM005929
Első szerző:	Damjanovich Sándor (biofizikus)
Cím:	The functional and fluorescence properties of Escherichia coli RNA polymerase reacted with fluorescamine / Damjanovich, S., Bahr, W., Jovin, T. M.
Dátum:	1977
Megjegyzések:	Fluorescamine (4-phenylspiro[furan-2,(3)1'-phthalan]-3,3'-dione) reacts rapidly with Escherichia coli RNA polymerase and produces a fluorescent derivative which is inactivated to an extent dependent upon reagent concentration. Excess fluorescamine is rapidly hydrolysed. Reaction is with xi-amino gruops of lysine residues in all subunits as revealed by gel electrophoresis and fluorescence scanning. 2. The extent of inactivation and fluorescence yield are diminished in the presence of added template, a finding which provides evidence for the existence of reactive and essential amino groups which can be at least partially shielded by DNA in the binary complexes. The relative decrease of fluorescence is greatest in the betabeta' subunits. Holoenzyme and core enzyme show essentially the same behavior. 3. The inactivation of activity by fluorescamine is primarily at the level of initiation. Template binding and chain propagation are less affected. 4. The enzyme derivatized by fluorescamine shows an intense fluorescence with a peak at 490 nm and an excitation maximum at 390 nm. The fluorescence lifetime is in the range of 3-8 ns and the emission is highly polarized. In reactions carried out at high ionic strength the fluorescence yield is approximately double that at low ionic strength and insensitive to the presence of template. 5. Energy transfer is observed between the derivatized enzyme as donor and ethidium bromide as acceptor in the presence of template to which both the enzyme and intercalating dye are bound. The transfer efficiency is a function of the relative concentrations and of the conditions of reaction with fluorescamine. An average transfer distance of approx. 4-5 nm has been calculated suggesting a close proximity between bound polymerase and helical regions of the template.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Binding Sites Dna DNA-Directed RNA Polymerase Energy Transfer enzymology Escherichia coli Ethidium Fluorescamine Fluorescence Kinetics Lysine metabolism pharmacology Protein Binding Protein Conformation Spectrometry, Fluorescence Spiro Compounds
Megjelenés:	European Journal of Biochemistry. - 72 : 3 (1977), p. 559-569. -
További szerzők:	Bahr, W. Jovin, Thomas M.
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5.

001-es BibID:	BIBFORM003923
Első szerző:	Damjanovich Sándor (biofizikus)
Cím:	The Role of the allosteric sites in the X-ray inactivation of phosphorylase b / S. Damjanovich, T. Sanner, A. Pihl
Dátum:	1967
Megjegyzések:	Crystalline rabbit muscle phosphorylase b was irradiated in dilute aqueous solution with X-rays. The enzyme was inactivated with a G-value of 0.09. Measurements of the K<sub>m</sub> values of the substrate, glucose-1-phosphate, and the allosteric activator, adenosine-5'-phosphate, demonstrated that these increased linearly with increasing radiation dose. The effect on the K<sub>m</sub> for the activator was 4 times greater than that on the K<sub>m</sub> for the substrate. The data indicate that the allosteric function is more sensitive to inactivation than the catalytic function. The enzyme SH-groups were destroyed by X-rays with a G-value of 1.8. Comparison with data on the inactivation of the enzyme by sulfhydryl blocking agents demonstrated that the X-ray destruction of sulfhydryl groups was sufficiently large to account for the X-ray inactivation of the enzyme. Blocking of two SH-groups with pCMB reduced the radiosensitivity of the enzyme by a factor of 2. Measurement of the K<sub>m</sub> values showed that the pCMB blocking protected preferentially the allosteric sites. The data indicate that the inactivation of phosphorylase b, both by sulfhydryl agents and by X-rays, involves largely an effect on the allosteric sites with loss of ability to bind the essential activator and consequent loss of ability to bind substrate.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban Allosteric regulation X-rays Irradiation Enzyme inhibitors Phosphorylase Allosteric enzymes
Megjelenés:	European Journal of Biochemistry. - 1 : 3 (1967), p. 347-352. -
További szerzők:	Sanner, Tore Pihl, Alexander
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6.

001-es BibID:	BIBFORM005943
Első szerző:	Jókay I.
Cím:	The role of SH-groups in the enzymic activity of phosphorylase-b / Jokay, I., Damjanovich, S., Toth, S.
Dátum:	1965
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény hazai lapban Adenine Nucleotides Chloromercuribenzoates Cysteine Ethylmaleimide Glucosyltransferases Glycogen Hexosephosphates Kinetics Mercaptoethanol metabolism Phosphorylase b Sulfhydryl Compounds
Megjelenés:	Archives of Biochemistry and Biophysics. - 112 : 3 (1965), p. 471-475. -
További szerzők:	Damjanovich Sándor (1936-2017) (biofizikus) Tóth S.
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7.

001-es BibID:	BIBFORM039514
Első szerző:	Matkó János (biológus)
Cím:	GPI-microdomains (membrane rafts) and signaling of the multi-chain interleukin-2 receptor in human lymphoma/leukemia T cell lines / Matko, J., Bodnar, A., Vereb, G., Bene, L., Vamosi, G., Szentesi, G., Szollosi, J., Gaspar, R., Horejsi, V., Waldmann, T. A., Damjanovich, S.
Dátum:	2002
ISSN:	0014-2956
Megjegyzések:	Subunits (alpha, beta and gamma) of the interleukin-2 receptor complex (IL-2R) are involved in both proliferative and activation-induced cell death (AICD) signaling of T cells. In addition, the signaling beta and gamma chains are shared by other cytokines (e.g. IL-7, IL-9, IL-15). However, the molecular mechanisms responsible for recruiting/sorting the alpha chains to the signaling chains at the cell surface are not clear. Here we show, in four cell lines of human adult T cell lymphoma/leukemia origin, that the three IL-2R subunits are compartmented together with HLA glycoproteins and CD48 molecules in the plasma membrane, by means of fluorescence resonance energy transfer (FRET), confocal microscopy and immuno-biochemical techniques. In addition to the beta and gamma(c) chains constitutively expressed in detergent-resistant membrane fractions (DRMs) of T cells, IL-2Ralpha (CD25) was also found in DRMs, independently of its ligand-occupation. Association of CD25 with rafts was also confirmed by its colocalization with GM-1 ganglioside. Depletion of membrane cholesterol using methyl-beta-cyclodextrin substantially reduced co-clustering of CD25 with CD48 and HLA-DR, as well as the IL-2 stimulated tyrosine-phosphorylation of STATs (signal transducer and activator of transcription). These data indicate a GPI-microdomain (raft)-assisted recruitment of CD25 to the vicinity of the signaling beta and gamma(c) chains. Rafts may promote rapid formation of a high affinity IL-2R complex, even at low levels of IL-2 stimulus, and may also form a platform for the regulation of IL-2 induced signals by GPI-proteins (e.g. CD48). Based on these data, the integrity of these GPI-microdomains seems critical in signal transduction through the IL-2R complex.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	European Journal Of Biochemistry. - 269 : 4 (2002), p. 1199-1208. -
További szerzők:	Dóczy-Bodnár Andrea (1970-) (biofizikus) Vereb György (1965-) (biofizikus, orvos) Bene László (1963-) (biofizikus) Vámosi György (1967-) (biofizikus) Szentesi Gergely (1976-) (kémia-fizika tanár) Szöllősi János (1953-) (biofizikus) Gáspár Rezső (1944-) (biofizikus) Horejsi, Václav Waldmann, Thomas A. Damjanovich Sándor (1936-2017) (biofizikus)
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8.

001-es BibID:	BIBFORM005984
Első szerző:	Matkó János (biológus)
Cím:	Correlation between activity and dynamics of the protein matrix of phosphorylase b / Janos Matko, Lajos Tron, Margit Balazs, Jozsef Hevessy, Bela Somogyi, Sandor Damjanovich
Dátum:	1980
Megjegyzések:	Quenching of the tryptophan fluorescence of phosphorylase b was studied by using iodide and acrylamide. Steady-state measurements indicated that all indole side chains were accessible to the nonionic quencher, although only 3 out of the total of 12 residues could be quenched by I-. From Stern--Volmer plots and the fluorescence lifetime data, it was concluded that the quenching was mainly of dynamic character. The value of the collisional quenching rate constant was found to be an order of magnitude less than that obtained in the case of fully exposed tryptophans. The relatively high activation energy, 30.9 kJ/mol, of the diffusion-controlled process and the value of the activation entropy suggest that the diffusion takes place in a fluctuating, structured medium. In spite of the application of sensitive fluorescent techniques, no gross conformational changes were found in the presence of acrylamide. However, the catalytic rate of the glycogen synthesis was decreased with the residual activity of the enzyme, proportional to the concentration of the probe. Binding of activator (AMP) and substrates (glucose 1-phosphate and glycogen) was found to be unaffected by acrylamide in concentrations applied (0--0.8 M). In a similar manner, activation enthalpy did not change in the presence of the quencher either. The complete reversibility of both activity inhibition and fluorescence quenching ruled out the irreversible denaturation of the enzyme or the covalent modification of any of the functional groups. We concluded that a model, suggesting the cross-correlation of activity and fluctuation, was consistent with the experimental findings.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Acrylamides Animal Diffusion enzymology Fluorescence Glucose Iodides Kinetics Ligands metabolism Muscles pharmacology Phosphorylase b Phosphorylases Protein Denaturation Rabbits Spectrometry,Fluorescence Tryptophan
Megjelenés:	Biochemistry. - 19 : 25 (1980), p. 5782-5786. -
További szerzők:	Trón Lajos (1941-) (biofizikus) Balázs Margit (1952-) (sejtbiológus, molekuláris genetikus) Hevessy József Somogyi Béla (1945-2006) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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9.

001-es BibID:	BIBFORM005946
Első szerző:	Matkó János (biológus)
Cím:	A method for continuous monitoring of phosphorylase b activity during glycogen degradation and synthesis / Matko, J., Tron, L., Damjanovich, S.
Dátum:	1978
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Animal biosynthesis enzymology Glycogen Light Liver Glycogen metabolism methods Muscles Phosphorylase b Phosphorylases Rabbits Scattering,Radiation Spectrometry, Fluorescence
Megjelenés:	Analytical Biochemistry. - 87 : 1 (1978), p. 249-252. -
További szerzők:	Trón Lajos (1941-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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10.

001-es BibID:	BIBFORM005992
Első szerző:	Somogyi Béla (biofizikus)
Cím:	Forster-type energy transfer as a probe for changes in local fluctuations of the protein matrix / Bela Somogyi, Janos Matko, Sandor Papp, Jozsef Hevessy, G. Rickey Welch, Sandor Damjanovich
Dátum:	1984
Megjegyzések:	Much evidence, on both theoretical and experimental sides, indicates the importance of local fluctuations (in energy levels, conformational substates, etc.) of the macromolecular matrix in the biological activity of proteins. We describe here a novel application of the Forster-type energy-transfer process capable of monitoring changes both in local fluctuations and in conformational states of macromolecules. A new energy-transfer parameter, f, is defined as an average transfer efficiency, [E], normalized by the actual average quantum efficiency of the donor fluorescence, [phi D]. A simple oscillator model (for a one donor-one acceptor system) is presented to show the sensitivity of this parameter to changes in amplitudes of local fluctuations. The different modes of averaging (static, dynamic, and intermediate cases) occurring for a given value of the average transfer rate, [kt], and the experimental requirements as well as limitations of the method are also discussed. The experimental tests were performed on the ribonuclease T1-pyridoxamine 5'-phosphate conjugate (a one donor-one acceptor system) by studying the change of the f parameter with temperature, an environmental parameter expectedly perturbing local fluctuations of proteins. The parameter f increased with increasing temperature as expected on the basis of the oscillator model, suggesting that it really reflects changes of fluctuation amplitudes (significant changes in the orientation factor, k2, as well as in the spectral properties of the fluorophores can be excluded by anisotropy measurements and spectral investigations). Possibilities of the general applicability of the method are also discussed.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Energy Transfer Fluorescence Kinetics Mathematics metabolism Phosphorylase b Protein Conformation Proteins Ribonuclease T1 Spectrometry,Fluorescence Thermodynamics
Megjelenés:	Biochemistry. - 23 : 15 (1984), p. 3403-3411. -
További szerzők:	Matkó János (1952-) (biológus) Papp Sándor Hevessy József Welch, Rickey G. Damjanovich Sándor (1936-2017) (biofizikus)
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