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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
Internet cím:	elektronikus változat elektronikus változat
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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.
Internet cím:	elektronikus változat elektronikus változat
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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
Internet cím:	elektronikus változat
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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)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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