Issue
Korean Journal of Chemical Engineering,
Vol.4, No.2, 182-186, 1987
GROWTH AND PLASMID STABILITY OF RECOMBINANT E. coli CELLS PRODUCING HEPATITIS B SURFACE ANTIGEN
The self-made recombinant plasmid vector, pKSB292, harboring the amino terminal-deleted surface antigen gene of hepatitis B virus(HBsAg) under the control of lpp+lac double promoters with the signal peptide region of the lipoprotein gene was tested for its effect on host cell growth and for the stability behaviour under various environmental conditions. The selection pressure imposed by the antibiotic ampicillin resulted in the more hindered cell growth as compared with the metabolic load caused by the recombinant plasmid in the host cell induced by the IPTG in the antibiotic-free medium. However the simultaneous application of both the antibiotic selection pressure and the metabolic load from the IPTG induction exhibited the lowest cell growth rate. The host cells harboring the recombinat plasmid, pKSB292, accounted for the majority of cell population under antibiotic selection pressure showing the apparently higher stability. The better growth rate of the recombinant cells and the higher HBsAg production rate could be achieved in the nonselective complex medium.