Biopolymers and cell. 2003; 19 (1): 81 - 88

Peculiarities of a target gene expression in the structure of the phage lambda-base vector and investigation of ways of its optimization

Yu. Slavchenko, V. A. Shmidt, S. I. Chernykh, V. A. Kordyum

High stability of the cloned gene in the lysogenic state and high copy number in the lytic state suggest a potential use of phage λ as an expression vector for overproduction of the extracellular recombinant proteins which release to the growth medium as a result of lysis of E. coli cells by phage. This paper describes the construction and characterization of phage λpIF carrying the two copy of an artificial gene for human α2 interferon (IFN) under control of the Ptrp tandem promoter. The expression of the foreign genes realized by thermal induction cells carrying the phage λpIF as well as by infection of recipient cells with this phage. In this study it was shown that the recombinant protein yield is dependent on a cell density at the time of thermal induction and the following temperature of producer cultivation. The increase of soluble target protein concentration in lysates after induction of recombinant phage was also observed using the phage λpIF contains amber-mutations in genes Q and R. The infection of recipient cells by phage λpIF resulted in higher IFN yield (about 40 mg per l) than thermal induction of the cells carrying the phage λ with target genes.