In vivo fluorescence observation of parasporal inclusion formation in Bacillus thuringiensis.

A recombinant gene expressing a Cry1Ac-GFP fusion protein with a molecular mass of approximately 160 kD was constructed to investigate the expression of cry1Ac, the localization of its gene product Cry1Ac, and its role in crystal development in Bacillus thuringiensis. The cry1Ac-gfp fusion gene under the control of the cry1Ac promoter was cloned into the plasmid pHT304, and this construct was designated pHTcry1Ac-gfp. pHTcry1Ac-gfp was transformed into the crystal-negative strain, HD-73 cry(-), and the resulting strain was named HD-73(-)(pHTcry1Ac-gfp).

[Deletion of spoIVF operon affects the sporulation and the production of crystal in Bacillus thuringiensis G03].

The spoIVF operon exists in Bacillus universally. Two proteins encoded by the spoIVF operon are essential for the sporulation of Bacillus subtilis. In this study, a spoIVF operon disruption mutant G03 (spoIVF-), in which the spoIVF operon was deleted, was constructed by homologous recombination.