Hydration of gamma-crystallins.
Four fractions of gamma-crystallins, B(II), C(IIIb), D(IIIa) and E(IVa), were isolated from bovine lenses. The hydration properties of each fraction were measured as a function of protein concentration. The freezable water content was obtained by differential scanning calorimetry and the total water content by thermogravimetric analysis. The difference yields the non-freezable (bound) water content of the crystallins. At physiological protein concentrations the order of the bound water content was C(IIIb) > D(IIIa) >> E(IVa) > B(II). This order was reversed between C and D and between B and E at low protein concentrations. This trend was evident whether the bound water was calculated as a percentage of the total water or as quantity per gram of gamma-crystallin.
Bettelheim
F A
FA
Department of Chemistry, Adelphi University, Garden City, NY 11530.
Reid
M B
MB
Garland
D
D
D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D003459:Crystallins / Q000032:analysis*; D011485:Protein Binding; D013329:Structure-Activity Relationship; D014867:Water / Q000032:analysis
D003459:Crystallins; D014867:Water