Investigation of some physico-chemical properties of muscular parvalbumins by means of the luminescence of their phenylalanyl residues.
The influence of pH, temperature and Ca2+-release on the phenylalanyl and tyrosyl fluorescene of muscular parvalbumins from white muscles of hake and carp has been investigated. Within the pH range from 7 to 8, Ca2+-saturated parvalbumins show a conformational change registered by fluorescence, that is associated with the release of some of the bound Ca2+. Removal of Ca2+ by means of EGTA (ethyleneglycolbis-(aminoethylether)tetra-acetic acid) considerably narrows the region of protein nativity, increases the accessibility of their chromophores to quencher ions (Cs+ and CNS-) and decreases their stability against heat denaturation. The usefulness of measurements of the phenylalanine fluorescence and of the tyrosine-phenylalanine energy transfer in the investigation of these and other proteins is discussed.
D000418:Albumins / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D002118:Calcium; D002347:Carps; D004533:Egtazic Acid; D005399:Fishes; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008163:Luminescent Measurements; D008433:Mathematics; D009124:Muscle Proteins / Q000032:analysis; D009132:Muscles / Q000032:analysis*; D010649:Phenylalanine / Q000032:analysis; D011485:Protein Binding; D011487:Protein Conformation; D011489:Protein Denaturation; D013050:Spectrometry, Fluorescence; D013696:Temperature
D000418:Albumins; D009124:Muscle Proteins; D010649:Phenylalanine; D004533:Egtazic Acid; D002118:Calcium