ABSTRACT
Objective:To construct a vector that suits the construction of large phage antibody libraries.Methods:Hie phage antibody vector p3MH was modified by insertion of synthesized oligos and PCR mediated site-specific mutations. Hie resultant vector was checked by expression of phage antibody, ELBA and in vivo recombination. Results: Vector pAL was obtained by following modifications of p3MH: insertion of Ioxp511 and loxp sequences, substitution of Lac promoter by Ara promoter, and modification of the cloning site for antibody genes. pAL was proved capable of expressing functional Fab phage antibodies under tighter control. In ere+ bacteria, pAL exhibited loxp-cre mediated recombination. Conclusion: pAL is useful for construction of large phage antibody libraries.