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 Bacillus thuringiensis serovar shandongiensis. The amino acid sequence of the parasporin-4, as deduced from the gene sequence, had low-level homologies of <30% with the established B. thuringiensis Cry proteins including the three known parasporins. When the gene was expressed in a recombinant of Escherichia coli 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).
Saitoh
Hiroyuki
H
Biotechnology and Food Research Institute, Fukuoka Industrial Technology Center, Fukuoka. saitou@fitc.pref.fukuoka.jp
Okumura
Shiro
S
Ishikawa
Tomoyuki
T
Akao
Tetsuyuki
T
Mizuki
Eiichi
E
Ohba
Michio
M
D001413:Bacillus thuringiensis / Q000235:genetics*; D001483:Base Sequence; D016923:Cell Death / Q000187:drug effects*; D045744:Cell Line, Tumor; D017931:DNA Primers; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D004731:Endotoxins / Q000235:genetics* / Q000494:pharmacology; D005798:Genes, Bacterial; D006801:Humans; D007938:Leukemia / Q000473:pathology*; D008969:Molecular Sequence Data; D013601:T-Lymphocytes / Q000187:drug effects
D017931:DNA Primers; D004731:Endotoxins; C412914:parasporin