The thermal transition of brain soluble proteins.
Soluble rat brain proteins undergo a thermal reversible denaturation in the range of 20 degrees C -65 degrees C. The thermal transition as studied in 0.25 M sucrose solution, is associated with changes in the proteins ionization capacity by the lowering of the isoionic solution pHfrom a value of 6.95 at 20 degrees C to 6.55 at 65 degrees C. The apparent enthalpy change delta H at the transition temperature (t=50 degrees C) is about 34 Kcal, heat capacity delta Cp about 1.75 Kcal, and apparent entrophy change deltaS 100 e.u. The data suggest that the thermal transition is predominantly a two-state process. A prolonged keeping of the protein solution at the increased temperature produces a partial reversibility of thermal transitions by a lowering of 5-HT cations fixing on the protein molecule.
D000818:Animals; D001923:Brain Chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D009419:Nerve Tissue Proteins; D011487:Protein Conformation; D011489:Protein Denaturation; D051381:Rats
D009419:Nerve Tissue Proteins