Immunochemical pulsed-labeling characterization of intermediates during hen lysozyme oxidative folding.

Autor: Jarrett, Nicole M., Djavadi-Ohaniance, Lisa, Willson, Richard C., Tachibana, Hideki, Goldberg, Michel E.
Zdroj: Protein Science: A Publication of the Protein Society; 2002, Vol. 11 Issue 11, p2584-2595, 12p
Abstrakt: Previous studies have shown that reduced hen egg white lysozyme refolds and oxidizes according to a linear model, in which the number of disulfide bonds increases sequentially. In this study, we describe the kinetics of native tertiary structure formation during the oxidative-renaturation of reduced hen egg white lysozyme, as monitored using an immunochemical pulsed-labeling method based on enzyme-linked immunosorbent assay (ELISA) in conjuction with two monoclonal antibodies (mAb). Each of these antibodies recognizes a separate face of the native lysozyme surface and, more importantly, each epitope is composed of discontinuous regions of the polypeptide chain. Renaturation kinetics were studied under the same refolding conditions as previous investigations of the kinetics of the regain of far-UV CD, fluorescence, enzymatic activity, and disulfide bonds. Comparison of our results with the results from those studies showed that the immunoreactivity (i.e., the native fold) of the α-domain appeared in intermediates containing two SS bonds only (C6-C127 and C30-C115), while the immunoreactivity of the β-domain appeared together with the formation of the third SS bond (C64-C80). Thus, the α-domain folds before the β-domain during the oxidative folding of reduced lysozyme. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index