Fig. 5

a SDS-PAGE analysis of anti ExoA-DI expression in E. coli. The results revealed a high level expression of scFv. HB2151 containing scFv inserts were grown and induced with IPTG for scFv secretion. Lane1, IgG; Lane 2, c9 scFv clone before induction; lane 3, 16 h hour after induction, lane 4, 22 h after induction. b Western blot analysis of the selected scFv antibody against ExoA-DI and native exotoxin A. Exo-DI and native exotoxin A was electrophoresed through a 12% SDS-polyacrylamide gel and transferred onto PVDF membrane along with a pre-stained protein size marker (abcam cat no. ab116027). The membrane was incubated with HRP conjugated protein L and developed using DAB substrate. The size of scFv was observed in the expected size of about 30 KD and 63 kDa. Lane 1, purified Exo A DI; Lane 2, Native exotoxin A; Lane 3, pre-stained size marker