Fig. 3

Molecular properties of recombinant CBL. a Coomassie brilliant blue staining of the recombinant CBL purified using anti-Flag bead from the 293F culture supernatant. b Chitin gel column chromatography of the recombinant CBL purified from 293F culture supernatant. The bound protein was eluted using 20 mM of acetic acid in 0.5-ml fractions at a flow rate of 0.1 ml/min and the fractions were monitored at 280 nm. The hemagglutination titer was assayed by RBC agglutination using trypsinized human erythrocytes. The eluted proteins were subjected to glycol chitin containing gel and Calcofluor White M2R staining was performed. c Comparison of chitin-binding activity. The purified natural CBL and recombinant CBL were incubated with chitin for indicated time intervals at 37 °C. The supernatant was evaluated by spectrophotometry to perform the residue-unbound CBL. The ratio of binding was calculated by OD ratio of unbound from control to CBL serial concentration groups. BSA is used as negative control