Predicting stability of alpha-helical, orthogonal-bundle proteins on surfaces.
The interaction of proteins with surfaces is a key phenomenon in many applications, but current understanding of the biophysics involved is lacking. At present, rational design of such emerging technologies is difficult as no methods or theories exist that correctly predict how surfaces influence protein behavior. Using molecular simulation and a coarse-grain model, this study illustrates for the first time that stability of proteins on surfaces can be correlated with tertiary structural elements for alpha-helical, orthogonal-bundle proteins. Results show that several factors contribute to stability on surfaces including the nature of the loop region where the tether is placed and the ability of the protein to freely rotate on the surface. A thermodynamic analysis demonstrates that surfaces stabilize proteins entropically and that any destabilization is an enthalpic effect. Moreover, the entropic effects are concentrated on the unfolded state of the protein while the ethalpic effects are focused on the folded state.
Wei
Shuai
S
Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, USA.
Knotts
Thomas A
TA
D008958:Models, Molecular; D055550:Protein Stability; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties; D013816:Thermodynamics; D044366:Transition Temperature
D011506:Proteins