Plasmids coding for B. Thuringiensis crystal protein, their production and their use in creating genetically engineered bacterial strains, the aforesaid strains per se and their use in producing said protein, said protein so-produced, insecticidal formulations comprising the same and a method of producing an insecticidal effect

摘要

The crystal protein of Bacillus thuringiensis is an insecticidal substance. Unfortunately growth phase limitations are exhibited by B. thuringiensis in producing this protein. This invention, however, provides a plasmid capable of replication in a bacterial host species and containing expressible heterologous DNA coding for the crystal protein of Bacillus thuringiensis and including an expression mechanism for said heterologous DNA which is recognized by the host species system but does not exhibit substantial growth phase limitations in the bacterial host species. Genetically engineered bacterial host strains transformed by the plasmids of the invention express B. thuringiensis crystal proteins without exhibiting the aforesaid growth phase limitations.