Effect of salts and sodium dodecyl sulfate on chaperone activity of camel alphaS(1)-CN: insulin as the target protein.
In this study camel alphaS(1)-casein (alphaS(1)-CN) was purified, using a two-step purification procedure. The anti-aggregation (chaperone-like) ability of the purified protein sample was examined in a wide range of experimental conditions and at different concentrations of camel alphaS(1)-CN, in the presence of salts and sodium dodecyl sulfate (SDS). To examine chaperone-like activity of camel alphaS(1)-CN, bovine pancreatic insulin was used as the target protein. Insulin aggregation performed chemically in the presence of 20 mM dithiotreitol (DTT) and was studied at 360 nm wavelength by UV-vis spectrophotometer. Camel alphaS(1)-CN exhibited a dose-dependent chaperone-like activity as the molar ratios of chaperone/target protein varied between 0 and 0.07. The presence of salts or surfactants changing the protein properties had an influence on chaperone capacity of camel alphaS(1)-CN. The results of UV-visible and fluorimetric measurements indicated that the salts neutralize the chaperone-like activity of casein due to dehydration effect and the increased association and aggregation of proteins, while SDS plays a role as chaperone and chaperone-like properties of camel alphaS(1)-CN enhanced in the presence of SDS due to the binding of the hydrophobic tail of SDS and alphaS(1)-CN to the exposed hydrophobic sites of insulin strongly preventing aggregation of insulin.
Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
Jalil
J
Badraghi
Reza
R
Yousefi
Ali Akbar
AA
Saboury
Ahmad
A
Sharifzadeh
Thomas
T
Haertlé
Faizan
F
Ahmad
Ali Akbar
AA
Moosavi-Movahedi
D000817:Anilino Naphthalenesulfonates / Q000378:metabolism; D000818:Animals; D002162:Camelus / Q000378:metabolism*; D002364:Caseins / Q000378:metabolism*; D002417:Cattle; D004229:Dithiothreitol / Q000494:pharmacology; D005453:Fluorescence; D057927:Hydrophobic and Hydrophilic Interactions; D007328:Insulin / Q000737:chemistry / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism*; D020836:Protein Structure, Quaternary; D012492:Salts / Q000494:pharmacology*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology*
C515594:8-anilino-1-naphthalenesulfonic acid; D000817:Anilino Naphthalenesulfonates; D002364:Caseins; D007328:Insulin; D018832:Molecular Chaperones; D012492:Salts; D012967:Sodium Dodecyl Sulfate; D004229:Dithiothreitol