Investigation of a Novel Bacillus thuringiensis Gene Encoding a Parasporal Protein, Parasporin-4, That Preferentially Kills Human Leukemic T Cells
A novel gene encoding a leukemic cell-killing parasporal protein, designated parasporin-4, was cloned from an isolate of <I>Bacillus thuringiensis</I> serovar <I>shandongiensis</I>. The amino acid sequence of the parasporin-4, as deduced from the gene sequence, had low-level homologies of <30% with the established <I>B. thuringiensis</I> Cry proteins including the three known parasporins. When the gene was expressed in a recombinant of <I>Escherichia coli</I> BL21(DE3), the parasporin-4 formed intracellular inclusion bodies. Alkali-solubilized and proteinase K-activated inclusion protein exhibited strong cytotoxic activity against human leukemic T cells (MOLT-4) and weak for normal T cells, but no adverse effect on human uterus cervix cancer cells (HeLa).
- Bioscience, biotechnology, and biochemistry
Bioscience, biotechnology, and biochemistry 70(12), 2935-2941, 2006-12-23
Japan Society for Bioscience, Biotechnology, and Agrochemistry