Gamma S-crystallin of bovine and human eye lens: solution structure, stability and folding of the intact two-domain protein and its separate domains.


Abstract

Human and bovine gammaS-crystallin (HgammaS and BgammaS) and their isolated N- and C-terminal domains were cloned and expressed as recombinant proteins in E. coli. HgammaS and BgammaS are found to be authentic according to their spectral and hydrodynamic properties. Both full-length proteins and isolated domains are monomeric and exhibit high thermal and pH stabilities. The thermodynamic characterization made use of chemically and thermally-induced equilibrium unfolding transitions at varying pH. In spite of its exemplary two-domain structure, gammaS-crystallin does not show bimodal unfolding characteristics. In the case of BgammaS, at pH 7.0, the C-terminal domain is less stable than the N-terminal one, whereas for HgammaS the opposite holds true. Differential scanning calorimetry confirms the results of chemically-induced equilibrium unfolding transitions. Over the whole pH range between 2.0 and 11.5, HgammaS-crystallin and its isolated domains (HgammaS-N and HgammaS-C) follow the two-state model. The two-state unfolding of the intact two-domain protein points to the close similarity of the stabilities of the constituent domains. Obviously, interactions between the domains do not contribute significantly to the overall stability of gammaS-crystallin. In contrast, the structurally closely related gammaB-crystallin owes much of its extreme stability to domain interactions. Study holds ProTherm entries: 12007, 12008, 12009 Extra Details: additive : DTT(5 mM), crystallins; differential scanning calorimetry; protein folding;,protein stability; domain interaction

Submission Details

ID: ey8Too7d3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:43 p.m.

Version: 1

Publication Details
Wenk M;Herbst R;Hoeger D;Kretschmar M;Lubsen NH;Jaenicke R,Biophys. Chem. (2000) Gamma S-crystallin of bovine and human eye lens: solution structure, stability and folding of the intact two-domain protein and its separate domains. PMID:11026675
Additional Information

Sequence Assay Result Units