The synergistic chaperoning operation in a Bi-chaperone system consisting of alpha-crystallin and beta-casein: bovine pancreatic insulin as the target protein

Colloids Surf B Biointerfaces. 2011 Nov 1;88(1):497-504. doi: 10.1016/j.colsurfb.2011.07.040. Epub 2011 Jul 23.


While chaperone activity of alpha-crystallin (α-Crs) is important in maintaining lens transparency that of beta-casein (β-CN) is vital to prevent the development of corpora amylacea (accumulation of amyloid deposits in mammary glands). These two chaperone proteins are amphiphilic, each contains distinct polar and non-polar regions in the structure. While polar domain of α-Crs is highly electropositive, the counterpart domain in β-CN is strongly electronegative. In this study a Bi-chaperone system consisting of α-Crs and β-CN with different molar ratios were used to prevent the chemical-induced insulin aggregation spectroscopically. As shown, α-Crs and β-CN in the Bi-chaperone system exhibit synergistic chaperoning operation which strongly depends to the specific ratio of the chaperone components. The results of both fluorescence study and native gel electrophoresis confirmed the non-covalent interactions between α-Crs and β-CN. Consequently the synergistic activity can be explained with the possible electrostatic interactions between their polar/charged domains which bring them in close proximity, allowing their synergistic chaperoning operation in the Bi-chaperone system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caseins / chemistry*
  • Cattle
  • Insulin / chemistry
  • Molecular Chaperones / chemistry*
  • alpha-Crystallins / chemistry*


  • Caseins
  • Insulin
  • Molecular Chaperones
  • alpha-Crystallins