Circular dichroism study on the early folding events of beta-lactoglobulin entrapped in wet silica gels.
beta-Lactoglobulin is a predominantly beta-sheet protein that folds by forming excess alpha-helices within milliseconds. In this study, the refolding of beta-lactoglobulin was dramatically decelerated by entrapping in wet nanoporous silica gel matrices, and monitored on a time scale of minutes or hours by far-UV circular dichroism spectroscopy. Analysis of kinetics and transient spectra allowed to define the sequence of folding events that consist of alpha-helical formation, beta-sheet core formation, and alpha-to-beta transition. The results suggest that the initially formed alpha-helices, presumably including the native alpha-helix, help to guide the formation of the adjacent beta-sheet core.
Shibayama
Naoya
N
Department of Physiology, Division of Biophysics, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi, Japan.
D002942:Circular Dichroism / Q000379:methods; D005782:Gels / Q000737:chemistry; D007782:Lactoglobulins / Q000737:chemistry*; D049329:Nanostructures; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012822:Silicon Dioxide / Q000737:chemistry; D014466:Ultraviolet Rays
D005782:Gels; D007782:Lactoglobulins; D012822:Silicon Dioxide