Calcium-induced changes in thyroglobulin conformation.
Polyethylene glycol solutions (10% w/v) were used to detect the effect of mono- and divalent cations on some properties of thyroglobulin. It is shown that in presence of 10% w/v polyethylene glycol in 0.01 M Tris-HCl, pH 7.5, calcium (less than 0.05 M) modifies the solubility, the sedimentation rate, and the Stokes' radius of thyroglobulin, while monovalent cations up to 0.6 M do not effect any of these properties. These findings can be explained by an increase in molecular compactness of thyroglobulin. Furthermore, it was shown that a synthetic polymer, polyethylene glycol, could be used to detect conformational changes.
D000818:Animals; D002118:Calcium; D002417:Cattle; D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D011092:Polyethylene Glycols; D011485:Protein Binding; D011487:Protein Conformation; D012995:Solubility; D013954:Thyroglobulin / Q000302:isolation & purification*; D013961:Thyroid Gland / Q000032:analysis
D011092:Polyethylene Glycols; D013954:Thyroglobulin; D002118:Calcium