Ultrasonic absorption of bovine serum albumin solutions in the frequency range 60 to 160 kHz.
The ultrasonic absorption of the globular protein bovine serum albumin in aqueous solution has been measured in the frequency range 60 to 160 kHz using a 2-1 spherical resonator. The effect of pH change and of the denaturants urea, guanidine hydrochloride, and sodium dodecyl sulfate on the absorption loss has been studied. It is concluded that a significant ultrasonic absorption process exists which is related to structural helix-coil transition equilibria. For native protein the maximum loss appears to occur at a frequency at least as low as 70 kHz for a pH of about 4.2. This loss process is distinct from those arising from proton-transfer equilibria perturbations which are manifest at pH 3.2 and 11.6 and at peak frequencies of 400 kHz and above.
D000818:Animals; D002417:Cattle; D019791:Guanidine; D006146:Guanidines / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012709:Serum Albumin / Q000378:metabolism*; D012967:Sodium Dodecyl Sulfate / Q000378:metabolism; D014465:Ultrasonics; D014508:Urea / Q000378:metabolism
D006146:Guanidines; D012709:Serum Albumin; D012967:Sodium Dodecyl Sulfate; D014508:Urea; D019791:Guanidine