Matches in SemOpenAlex for { <https://semopenalex.org/work/W2051910367> ?p ?o ?g. }
Showing items 1 to 90 of
90
with 100 items per page.
- W2051910367 endingPage "282" @default.
- W2051910367 startingPage "270" @default.
- W2051910367 abstract "The following was observed in studies of the effect of temperature on the intensity of X-ray-induced emission from powders of aromatic amino acids and proteins: The thermal coefficients for quenching of both fluorescence and phosphorescence are much different at temperatures below about 150 °K and above 240 °K. The ratios of the coefficients measured in the two temperature regions varied from 3 to 50 in the four compounds studied. The Eq for tryptophan fluorescence in powders exposed to X-rays near 300 °K is much less than the coefficient for quenching ultraviolet-induced fluorescence from tryptophan in solution. The quenching coefficient for fluorescence is invariably smaller than that for phosphorescence. The Eq = 0.21 ± .07 eV per molecule for the quenching of trypsin phosphorescence in the range T > 200 °K is essentially the same as that for tyrosine phosphorescence. This value is approximately twice that of 0.1 eV per molecule for the thermal enhancement of trypsin inactivation by ionizing radiations in the same temperature range. Crude measurements suggest that the thermal coefficient for quenching of trypsin fluorescence is also less than the corresponding activation energies for trypsin inactivation. Analysis of the data has led to the following conclusions: (1) Quenching is a function of the macromolecular organization of proteins. (2) Thermal enhancement of enzyme inactivation yields does not depend critically upon indiscriminate quenching to prevent emissive loss of potential inactivating energy from the irradiated molecules. (3) Either the interaction of specific excited aromatic residues with radiosensitive structures does not provide a large contribution to enzyme inactivation or the specific interactions account for only a small fraction of total quenching. The present results emphasize again the differences between the excitation events produced by X-ray-induced electrons and low-energy ultraviolet. Although trypsin fluorescence appears to be from tryptophan, X-rays cause a great enhancement in trypsin of phosphorescence typical of that from tyrosine: excitations by “ionizing” radiations must be involved in intersystem crossing with high probability. “Red” components not found in ultraviolet-induced emission are also observed." @default.
- W2051910367 created "2016-06-24" @default.
- W2051910367 creator A5010636367 @default.
- W2051910367 creator A5032605992 @default.
- W2051910367 creator A5036102976 @default.
- W2051910367 date "1965-08-01" @default.
- W2051910367 modified "2023-09-23" @default.
- W2051910367 title "Effect of temperature on X-ray-induced light emission from powders of amino acids and trypsin" @default.
- W2051910367 cites W1816966864 @default.
- W2051910367 cites W1965970092 @default.
- W2051910367 cites W1971715594 @default.
- W2051910367 cites W1980567865 @default.
- W2051910367 cites W1985772804 @default.
- W2051910367 cites W2020708804 @default.
- W2051910367 cites W2040383753 @default.
- W2051910367 cites W2050603110 @default.
- W2051910367 cites W207869059 @default.
- W2051910367 cites W2118802466 @default.
- W2051910367 cites W2267287463 @default.
- W2051910367 doi "https://doi.org/10.1016/0003-9861(65)90188-8" @default.
- W2051910367 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/5861990" @default.
- W2051910367 hasPublicationYear "1965" @default.
- W2051910367 type Work @default.
- W2051910367 sameAs 2051910367 @default.
- W2051910367 citedByCount "17" @default.
- W2051910367 countsByYear W20519103672012 @default.
- W2051910367 crossrefType "journal-article" @default.
- W2051910367 hasAuthorship W2051910367A5010636367 @default.
- W2051910367 hasAuthorship W2051910367A5032605992 @default.
- W2051910367 hasAuthorship W2051910367A5036102976 @default.
- W2051910367 hasConcept C113196181 @default.
- W2051910367 hasConcept C121332964 @default.
- W2051910367 hasConcept C121745418 @default.
- W2051910367 hasConcept C153294291 @default.
- W2051910367 hasConcept C178790620 @default.
- W2051910367 hasConcept C181199279 @default.
- W2051910367 hasConcept C181500209 @default.
- W2051910367 hasConcept C181817918 @default.
- W2051910367 hasConcept C184779094 @default.
- W2051910367 hasConcept C185592680 @default.
- W2051910367 hasConcept C2776706248 @default.
- W2051910367 hasConcept C2780340462 @default.
- W2051910367 hasConcept C32909587 @default.
- W2051910367 hasConcept C39353612 @default.
- W2051910367 hasConcept C515207424 @default.
- W2051910367 hasConcept C55493867 @default.
- W2051910367 hasConcept C62520636 @default.
- W2051910367 hasConcept C75473681 @default.
- W2051910367 hasConcept C91881484 @default.
- W2051910367 hasConceptScore W2051910367C113196181 @default.
- W2051910367 hasConceptScore W2051910367C121332964 @default.
- W2051910367 hasConceptScore W2051910367C121745418 @default.
- W2051910367 hasConceptScore W2051910367C153294291 @default.
- W2051910367 hasConceptScore W2051910367C178790620 @default.
- W2051910367 hasConceptScore W2051910367C181199279 @default.
- W2051910367 hasConceptScore W2051910367C181500209 @default.
- W2051910367 hasConceptScore W2051910367C181817918 @default.
- W2051910367 hasConceptScore W2051910367C184779094 @default.
- W2051910367 hasConceptScore W2051910367C185592680 @default.
- W2051910367 hasConceptScore W2051910367C2776706248 @default.
- W2051910367 hasConceptScore W2051910367C2780340462 @default.
- W2051910367 hasConceptScore W2051910367C32909587 @default.
- W2051910367 hasConceptScore W2051910367C39353612 @default.
- W2051910367 hasConceptScore W2051910367C515207424 @default.
- W2051910367 hasConceptScore W2051910367C55493867 @default.
- W2051910367 hasConceptScore W2051910367C62520636 @default.
- W2051910367 hasConceptScore W2051910367C75473681 @default.
- W2051910367 hasConceptScore W2051910367C91881484 @default.
- W2051910367 hasIssue "2" @default.
- W2051910367 hasLocation W20519103671 @default.
- W2051910367 hasLocation W20519103672 @default.
- W2051910367 hasOpenAccess W2051910367 @default.
- W2051910367 hasPrimaryLocation W20519103671 @default.
- W2051910367 hasRelatedWork W1964083636 @default.
- W2051910367 hasRelatedWork W1965579221 @default.
- W2051910367 hasRelatedWork W199160946 @default.
- W2051910367 hasRelatedWork W1997841513 @default.
- W2051910367 hasRelatedWork W2025531145 @default.
- W2051910367 hasRelatedWork W2047678380 @default.
- W2051910367 hasRelatedWork W2055938034 @default.
- W2051910367 hasRelatedWork W2063158838 @default.
- W2051910367 hasRelatedWork W2085316155 @default.
- W2051910367 hasRelatedWork W2101718937 @default.
- W2051910367 hasVolume "111" @default.
- W2051910367 isParatext "false" @default.
- W2051910367 isRetracted "false" @default.
- W2051910367 magId "2051910367" @default.
- W2051910367 workType "article" @default.