Identifying kinetically stable proteins with capillary electrophoresis.
Unlike most proteins, which are in equilibrium with partially and globally unfolded conformations, kinetically stable proteins (KSPs) are trapped in their native conformations and are often resistant to harsh environment. Based on a previous correlation between kinetic stability (KS) and a protein's resistance to sodium dodecyl sulfate (SDS), we show here a simple method to identify KSPs by SDS-capillary electrophoresis (CE). Control non-KSPs were fully denatured by SDS and formed protein:SDS complexes that exhibited similar mobility in CE. In contrast, KSPs bound fewer SDS molecules, and showed a very different migration time and peak pattern in CE, thereby providing some insight about the structural heterogeneity of SDS:protein complexes and the relative KS of the various proteins.
Zhang
Songjie
S
Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Xia
Ke
K
Chung
Wai Keen
WK
Cramer
Steven M
SM
Colón
Wilfredo
W
D019075:Electrophoresis, Capillary / Q000379:methods*; D007700:Kinetics; D011487:Protein Conformation; D017510:Protein Folding; D055550:Protein Stability; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism
D011506:Proteins