The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform

B Nock - One of the best experts on this subject based on the ideXlab platform.

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of Neuroscience Methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    Abstract A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of neuroscience methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of less than 1% and 6%, respectively. The assay was used to evaluate several potential methods for removing Digitonin from biological samples (Digitonin extracts from guinea pig brain membranes). Dialysis and G-25 Sephadex chromatography were ineffective. However, protein and Digitonin can be effectively separated by ammonium sulfate precipitation followed by dialysis. The kappa 1 opioid receptor survived these procedures with no change in affinity for [3H]U-69,593. In conclusion, the hemolytic assay for Digitonin appears to provide a practical means for determining detergent concentrations during receptor purification and characterization and for evaluating potential methods for detergent removal. Although an in depth analysis of the assay was carried out only for Digitonin, CHAPS and deoxycholate also caused 50% hemolysis at concentrations well below those commonly used for receptor solubilization and, therefore, the general assay procedures might have applicability for measurement of these and perhaps other detergents used in receptor solubilization as well.

B W Moore - One of the best experts on this subject based on the ideXlab platform.

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of Neuroscience Methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    Abstract A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of neuroscience methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of less than 1% and 6%, respectively. The assay was used to evaluate several potential methods for removing Digitonin from biological samples (Digitonin extracts from guinea pig brain membranes). Dialysis and G-25 Sephadex chromatography were ineffective. However, protein and Digitonin can be effectively separated by ammonium sulfate precipitation followed by dialysis. The kappa 1 opioid receptor survived these procedures with no change in affinity for [3H]U-69,593. In conclusion, the hemolytic assay for Digitonin appears to provide a practical means for determining detergent concentrations during receptor purification and characterization and for evaluating potential methods for detergent removal. Although an in depth analysis of the assay was carried out only for Digitonin, CHAPS and deoxycholate also caused 50% hemolysis at concentrations well below those commonly used for receptor solubilization and, therefore, the general assay procedures might have applicability for measurement of these and perhaps other detergents used in receptor solubilization as well.

M Bruckner - One of the best experts on this subject based on the ideXlab platform.

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of Neuroscience Methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    Abstract A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of neuroscience methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of less than 1% and 6%, respectively. The assay was used to evaluate several potential methods for removing Digitonin from biological samples (Digitonin extracts from guinea pig brain membranes). Dialysis and G-25 Sephadex chromatography were ineffective. However, protein and Digitonin can be effectively separated by ammonium sulfate precipitation followed by dialysis. The kappa 1 opioid receptor survived these procedures with no change in affinity for [3H]U-69,593. In conclusion, the hemolytic assay for Digitonin appears to provide a practical means for determining detergent concentrations during receptor purification and characterization and for evaluating potential methods for detergent removal. Although an in depth analysis of the assay was carried out only for Digitonin, CHAPS and deoxycholate also caused 50% hemolysis at concentrations well below those commonly used for receptor solubilization and, therefore, the general assay procedures might have applicability for measurement of these and perhaps other detergents used in receptor solubilization as well.

A L Giordano - One of the best experts on this subject based on the ideXlab platform.

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of Neuroscience Methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    Abstract A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of

  • A simple, highly sensitive assay for measurement of Digitonin during receptor solubilization.
    Journal of neuroscience methods, 1992
    Co-Authors: B W Moore, A L Giordano, M Bruckner, B Nock
    Abstract:

    A simple and highly sensitive assay for measuring total Digitonin in biological samples is described. The assay is based on the ability of Digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of less than 1% and 6%, respectively. The assay was used to evaluate several potential methods for removing Digitonin from biological samples (Digitonin extracts from guinea pig brain membranes). Dialysis and G-25 Sephadex chromatography were ineffective. However, protein and Digitonin can be effectively separated by ammonium sulfate precipitation followed by dialysis. The kappa 1 opioid receptor survived these procedures with no change in affinity for [3H]U-69,593. In conclusion, the hemolytic assay for Digitonin appears to provide a practical means for determining detergent concentrations during receptor purification and characterization and for evaluating potential methods for detergent removal. Although an in depth analysis of the assay was carried out only for Digitonin, CHAPS and deoxycholate also caused 50% hemolysis at concentrations well below those commonly used for receptor solubilization and, therefore, the general assay procedures might have applicability for measurement of these and perhaps other detergents used in receptor solubilization as well.

David S. Kliger - One of the best experts on this subject based on the ideXlab platform.

  • effect of Digitonin on the rhodopsin meta i meta ii equilibrium
    Photochemistry and Photobiology, 2005
    Co-Authors: Istvan Szundi, James W. Lewis, David S. Kliger
    Abstract:

    Absorbance difference spectra were recorded from 10 μs to 540 ms after photoexcitation of sonicated suspensions of hypotonically washed bovine rod outer segments with varying amounts of the detergent Digitonin added (0 to 2%) at 20°C. Metarhodopsin I480 and metarhodopsin II displayed the expected anomalous pH dependence at pH 6 and 8 (i.e. opposite to that expected from direct protonation of the chromophore Schiff base). However, increasing levels of Digitonin eliminated the pH dependence of the equilibrium, and at 2% Digitonin the pH 6 and pH 8 data were both similar to the data collected at pH 8 without Digitonin. Addition of 0.5% azolectin restored approximately 50% of the anomalous pH dependence at pH 6 in the 2% Digitonin sample. The possibility that Digitonin induced large-scale aggregation of rhodopsin in the disk membrane that could be reversed by azolectin was tested using time-resolved linear dichroism. Those results showed that even 0.3% Digitonin disrupted the membrane, and no large aggregates were detectable under any conditions. Thus, Digitonin reduces the activity of a component of the disk membrane required for metarhodopsin II formation, and that deficiency can be compensated for by azolectin.

  • Effect of Digitonin on the Rhodopsin Meta I–Meta II Equilibrium¶
    Photochemistry and photobiology, 2005
    Co-Authors: Istvan Szundi, James W. Lewis, David S. Kliger
    Abstract:

    Absorbance difference spectra were recorded from 10 μs to 540 ms after photoexcitation of sonicated suspensions of hypotonically washed bovine rod outer segments with varying amounts of the detergent Digitonin added (0 to 2%) at 20°C. Metarhodopsin I480 and metarhodopsin II displayed the expected anomalous pH dependence at pH 6 and 8 (i.e. opposite to that expected from direct protonation of the chromophore Schiff base). However, increasing levels of Digitonin eliminated the pH dependence of the equilibrium, and at 2% Digitonin the pH 6 and pH 8 data were both similar to the data collected at pH 8 without Digitonin. Addition of 0.5% azolectin restored approximately 50% of the anomalous pH dependence at pH 6 in the 2% Digitonin sample. The possibility that Digitonin induced large-scale aggregation of rhodopsin in the disk membrane that could be reversed by azolectin was tested using time-resolved linear dichroism. Those results showed that even 0.3% Digitonin disrupted the membrane, and no large aggregates were detectable under any conditions. Thus, Digitonin reduces the activity of a component of the disk membrane required for metarhodopsin II formation, and that deficiency can be compensated for by azolectin.