Gel electrophoresis
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis
(SDS-PAGE) and native polyacrylamide gel electrophoresis
(Native-PAGE) were carried out on Bio-Rad (St. Louis, Mo., U.S.A.)
pre-cast 10% to 20% and 4% to 15% gradient polyacrylamide TrisHCl
gel, respectively, using the Bio-Rad Criterion cell at a constant
voltage (200 V). The gels were stained with Bio-Rad Coomassie Blue
R-250. Bio-Rad Precision Plus Protein Standards (10 to 250 kDa)
and Amersham Pharmacia Biotech (Uppsala, Sweden) High Molecular
Weight Calibration Kit (66 to 669 kDa) were used as molecular
markers for SDS- and Native-PAGE, respectively.