FIG. 1.

Cloning scheme of the bacterial expression vector pBM1.1. The expression module (a) is composed of the signal peptide of the pectate lyase gene (pelB), the IPTG-inducible T7 lac operon from the original pET vector (36), the synthetic His₁₀ cluster (His) (20), the variable-region genes (V_H and V_L) connected by (Gly₄Ser)₃ (linker), and the ETA′ gene. Plasmid pBM1.1 (b) contains the expression module, a kanamycin resistance gene (Kan^r), an E. coli origin of replication (pBR322 origin), an M13 origin of replication (f1 origin), and the lactose repressor gene (lacI). The binding single-chain variable fragments (scFv) are fused to ETA′.