Matches in SemOpenAlex for { <https://semopenalex.org/work/W2003921530> ?p ?o ?g. }
Showing items 1 to 63 of
63
with 100 items per page.
- W2003921530 abstract "Using time-resolved nanosecond fluorescence spectroscopy, we investigated the conformational changes of skeletal and cardiac troponin C. A thiol specific fluorescence probe N-(iodoacety1)-N'-(5-sulfo-1-naphthyl)- ethylenediamine (IAEDANS) was attached to cysteine 98 of skeletal troponin C (STnC) and 2-(4'-iodoacetamido-anilino)-naphthalene-6-sulfonic acid (IAANS) was linked to cysteine 35 and 84 of cardiac troponin C (CTnC). With excitation at 340 nm for STnC-IAEDANS and at 335 nm for CTnC-IAANS, apo-STnC and apo-CTnC exhibited biexponential decay kinetics. At 20°C and neutral pH, the following lifetimes were observed: (1) apo-STnC, 9 and 16 ns, and (2) apo-CTnC, 2.3 and 7 ns. The long lived component of the emission in STnC-IAEDANS comprised ~ 61% of observed intensity, however, the corresponding component in CTnC contributed only. A decrease of pH from 7.2 to 5.2 induced an increase of the lifetimes 20% (STnC) and 10% (CTnC). These results suggest that Cys-98 of STnC and Cys-35 and Cys-84 of CTnC became less quenched by their neighboring residues at low pH. Addition of guanidine hydrochloride to STnC resulted in a decrease of ~30% of both lifetimes. The lifetimes increased slightly when the temperature was lowered. Variation of solution viscosity by addition of sucrose did not affect the long component of the lifetimes of STnC. However, the short component did sense a viscosity effect. These results suggest that there was likely a chromophore heterogeneity which may arise from differences in conformation, environment, and or ionization of the excited state of the chromophore. At 20°C and neutral pH, two rotational correlation times were observed: (1) apo-STnC, - 1.2 ns, .2 1 11.3 ns, and (2) apo-CTnC, .~ 0.6 ns, .2 1 13.6 ns. The short rotational correlation times likely reflect rapid motions of the chromophores covalently attached to the side chain of the cysteine residues, and the long correlation times reflect the overall protein motions. The .2 values suggest that both proteins were not highly asymmetric at neutral pH. In the presence of Ca2+, at 20A‚°C and neutral pH the rotational correlation times were (1) STnC, .1 ~ 2.1 ns, .2 1 13.9 ns, and (2) CTnC, .1 ~ 1.9 ns, .2 1 13.0 ns. A decrease of pH from 7.2 to 5.2 led to an increase of .2 ~ 20% for STnC and a reduction of .2 ~ 7% for CTnC. The two proteins appear to have different hydrodynamic properties in an acidic environment." @default.
- W2003921530 created "2016-06-24" @default.
- W2003921530 creator A5007164613 @default.
- W2003921530 creator A5061700068 @default.
- W2003921530 creator A5087363458 @default.
- W2003921530 date "1988-06-24" @default.
- W2003921530 modified "2023-09-23" @default.
- W2003921530 title "Time-Resolved Fluorescence Studies Of Ph Effects On The Conformation Of Troponin C" @default.
- W2003921530 doi "https://doi.org/10.1117/12.945378" @default.
- W2003921530 hasPublicationYear "1988" @default.
- W2003921530 type Work @default.
- W2003921530 sameAs 2003921530 @default.
- W2003921530 citedByCount "0" @default.
- W2003921530 crossrefType "proceedings-article" @default.
- W2003921530 hasAuthorship W2003921530A5007164613 @default.
- W2003921530 hasAuthorship W2003921530A5061700068 @default.
- W2003921530 hasAuthorship W2003921530A5087363458 @default.
- W2003921530 hasConcept C121332964 @default.
- W2003921530 hasConcept C12554922 @default.
- W2003921530 hasConcept C126322002 @default.
- W2003921530 hasConcept C133927893 @default.
- W2003921530 hasConcept C148898269 @default.
- W2003921530 hasConcept C185592680 @default.
- W2003921530 hasConcept C36036425 @default.
- W2003921530 hasConcept C500558357 @default.
- W2003921530 hasConcept C62520636 @default.
- W2003921530 hasConcept C71924100 @default.
- W2003921530 hasConcept C86803240 @default.
- W2003921530 hasConcept C91881484 @default.
- W2003921530 hasConceptScore W2003921530C121332964 @default.
- W2003921530 hasConceptScore W2003921530C12554922 @default.
- W2003921530 hasConceptScore W2003921530C126322002 @default.
- W2003921530 hasConceptScore W2003921530C133927893 @default.
- W2003921530 hasConceptScore W2003921530C148898269 @default.
- W2003921530 hasConceptScore W2003921530C185592680 @default.
- W2003921530 hasConceptScore W2003921530C36036425 @default.
- W2003921530 hasConceptScore W2003921530C500558357 @default.
- W2003921530 hasConceptScore W2003921530C62520636 @default.
- W2003921530 hasConceptScore W2003921530C71924100 @default.
- W2003921530 hasConceptScore W2003921530C86803240 @default.
- W2003921530 hasConceptScore W2003921530C91881484 @default.
- W2003921530 hasLocation W20039215301 @default.
- W2003921530 hasOpenAccess W2003921530 @default.
- W2003921530 hasPrimaryLocation W20039215301 @default.
- W2003921530 hasRelatedWork W1977311040 @default.
- W2003921530 hasRelatedWork W1989651558 @default.
- W2003921530 hasRelatedWork W2011814184 @default.
- W2003921530 hasRelatedWork W2021578704 @default.
- W2003921530 hasRelatedWork W2028507415 @default.
- W2003921530 hasRelatedWork W2036775122 @default.
- W2003921530 hasRelatedWork W2037059412 @default.
- W2003921530 hasRelatedWork W2042695655 @default.
- W2003921530 hasRelatedWork W2045080314 @default.
- W2003921530 hasRelatedWork W2056276010 @default.
- W2003921530 hasRelatedWork W2069573262 @default.
- W2003921530 hasRelatedWork W2070509667 @default.
- W2003921530 hasRelatedWork W2128260444 @default.
- W2003921530 hasRelatedWork W2284148802 @default.
- W2003921530 hasRelatedWork W2410550410 @default.
- W2003921530 isParatext "false" @default.
- W2003921530 isRetracted "false" @default.
- W2003921530 magId "2003921530" @default.
- W2003921530 workType "article" @default.