OXIDATION OF FE(II) HORSE HEART CYTOCHROME-C BY ULTRASOUND WAVES

In aqueous solution, acoustically induced cavitation produces the coll apse of bubbles containing gas and water-vapor, producing free radical s by the homolysis of the water molecules. Generally, under these extr eme physical conditions, the secondary and tertiary structures of the proteins result are altered and denaturation phenomena are often obser ved. This paper discusses the evidence that, in the presence of argon and in oxygen-free experimental environment, the reduced horse heart c ytochrome c, instead of undergoing a denaturation process, is oxidized to ferric-cytochrome c. Kinetic and circular dichroism measurements p erformed after ultrasound irradiation at a frequency of 38 kHz are rep orted. A possible correlation between ultrasound induced molecular dam age to the tertiary structure of the proteins and their own extension of helix content is also hypothesized.