2.2. SDS–polyacrylamide gel electrophoresis
(SDS–PAGE)
SDS–PAGE was done according to the method
of Laemmli (1970). Briefly, samples were suspended
in loading buffer (0.5 mM Tris–Cl, pH
6.8, 2.5 ml; 10% sodium dodecyl sulfate, 4 ml;
glycerol, 2 ml; b-mercaptoethanol, 1 ml; and
deionized distilled water, 0.5 ml), boiled at 95°C
for 5 min, loaded into the wells of 5% (YHV) and
10% (CBV) SDS–PAGE, and electrophoresed at
200 V for 45 min.