Study on segregrational stability of pbc. 16-derived plasmid in bacillus thuringiensis subsp. kurstaki. (Thai)

Abstract

A 6100-base pair (bp) plasmid vector pBCE was derived from pBCX (6900-bp). A 800-bp
Eco RI fragment of pBCX was deleted out and the remaining plasmid was religated. Both of them were comprised of Gram-positive plasmid pBC16 and Gram-negative plasmid pBluescript II KS. They act as bifunctional plasmids conferring ampicillin and tetracycline resistance in Escherichia coli but only tetracycline resistance in Bacillus thuringiensis (Bt). They were structurally stable in both E. coli and Bt. However, pBCX was more segregationally stable than pBCE in Bt subsp. kurstaki, which may be correlated with tetracycline resistant gene expression.