Book of Abstracts: Albany 2009

category image Albany 2009
Conversation 16
June 16-20 2009
© Adenine Press (2008)

Identifying Kinetically Stable Proteins via Electrophoresis Methods

Most proteins are in equilibrium with partially and globally unfolded conformations. In contrast, kinetically stable proteins (KSPs) are trapped by an energy barrier in a specific state, unable to transiently sample other conformations. Among many potential roles, it appears that kinetic stability (KS) is a feature used by nature to allow proteins to maintain activity under harsh conditions, and to preserve the structure of proteins that are prone to misfolding. The biological and pathological significance of KS remain poorly understood due to the lack of simple experimental methods to identify this property, and its infrequent occurrence in proteins. Based on our previous correlation between KS and a protein's resistance to the denaturing detergent sodium dodecyl sulfate (SDS), we show here two electrophoresis methods to indentify KSPs. Diagonal two-dimensional (D2D) SDS-polyacrylamide gel electrophoresis (PAGE) is a simple assay to identify KSPs in complex mixtures, and allows the proteomics-level identification of KSPs in different systems. The other simple and quick method to probe KSPs is capillary electrophoresis (CE). Different KSPs have their own characteristic charge-to-mass ratio that results in different CE mobility, thereby revealing the extent of SDS binding, and consequently, its KS. The study of KS using these methods may eventually lead to a better understanding of KS and its biological and pathological significance.

Ke Xia
Songjie Zhang
Wilfredo Colón

Department of Chemistry
Rensselaer Polytechnic Institute
Troy, NY, 12180