title: Structural changes induced in proteins by therapeutic ultrasounds.
abstract: The structural effect induced by therapeutic ultrasound on proteins in aqueous solution has been investigated with FTIR spectroscopy, UV-VIS spectroscopy, circular dichroism and light scattering. Six proteins (cytochrome, lysozyme, myoglobin, bovine serum albumin, trypsinogen, and alpha-chymotrypsinogen A) with different molecular weight and secondary structure have been studied. The experiment has been performed using an ultrasound source at resonant frequency of 1 MHz and sonication times of 10, 20, 30, 40, 50, and 60 min. A different behaviour of proteins under sonication depends on the dominant secondary structure type (alpha-helix or beta-sheets) and on the grade of the ordered structure. The results suggest that the free radicals, produced by water sonolysis, have an important role in the changes of structural order.
authors.affiliation: Dipartimento di Fisica, Università Di Roma Sapienza, Piazzale A. Moro 5, 00185 Roma, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Marchioni
authors.forename: E
authors.initials: E
authors.lastname: Riccardi
authors.forename: S
authors.initials: S
authors.lastname: Spinelli
authors.forename: F
authors.initials: F
authors.lastname: Dell'Unto
authors.forename: P
authors.initials: P
authors.lastname: Grimaldi
authors.forename: A
authors.initials: A
authors.lastname: Bedini
authors.forename: C
authors.initials: C
authors.lastname: Giliberti
authors.forename: L
authors.initials: L
authors.lastname: Giuliani
authors.forename: R
authors.initials: R
authors.lastname: Palomba
authors.forename: A
authors.initials: A
authors.lastname: Congiu Castellano
mesh_terms: D002942:Circular Dichroism; D005609:Free Radicals; D008970:Molecular Weight; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted; D017550:Spectroscopy, Fourier Transform Infrared; D014464:Ultrasonic Therapy; D014465:Ultrasonics
chemical_list: D005609:Free Radicals; D011506:Proteins