Kinetically stable proteins (KSPs) refer to proteins that are trapped by an energy barrier in a specific state, unable to transiently sample other conformations. Kinetic stability (KS) may be a feature used by nature to protect the native structure of a protein against misfolding or harsh conditions. The biological and pathological significance of KS remains poorly understood, in part due to the lack of simple experimental methods to identify this property at a proteomics level. Based on our previously discovered correlation between KS and a protein’s resistance to sodium dodecyl sulfate (SDS), we show here three electrophoreses methods for identifying KSPs in complex mixtures using proteomics analysis or for quantifying the KS of proteins. We have applied these methods on diverse biological systems, including microorganisms, human plasma, and beans. Novel insight is emerging about the biological and pathological significance of this intriguing biophysical property of certain proteins.

This research has been supported by NSF Award 1158375

References

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