The cytotoxicity of Bacillus thuringiensis subsp. coreanensis A1519 strain against the human leukemic T cell.
A novel cytotoxic protein was isolated from the crystal produced by Bacillus thuringiensis subsp. coreanensis A1519 strain. Upon treatment of the crystal proteins by proteinase K, the significant cytotoxicity toward the leukemic T cell, MOLT-4, was exhibited. The microscopic observation indicated that the cell death was accompanied by no extensive rupture of the cell membrane. It was, therefore, suggested that the cell death of MOLT-4 was induced through a mechanism other than the colloid-osmotic swelling and cell lysis as caused by hitherto known B. thuringiensis crystal proteins. The 29-kDa polypeptide proved to be an active component of the proteinase K-digested A1519 crystal proteins. EC(50) of the purified 29-kDa polypeptide was 0.078 microg/ml. The N-terminal amino acid sequence of the 29-kDa polypeptide shared no significant homology with all the known proteins, suggesting that this polypeptide belong to a new family of B. thuringiensis crystal proteins. In the ligand blotting analysis, specific binding proteins for the 29-kDa polypeptide were detected from the cell membrane of MOLT-4.
Namba
Akitoshi
A
Laboratory of Gene Engineering, Faculty of Engineering, Department of Bioscience and Biotechnology, Okayama University, Tsushima-Naka 3-1-1, Okayama-shi, Okayama 700-8530, Japan.
Yamagiwa
Masashi
M
Amano
Hiromi
H
Akao
Tetsuyuki
T
Mizuki
Eiichi
E
Ohba
Michio
M
Sakai
Hiroshi
H
D000970:Antineoplastic Agents / Q000494:pharmacology*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D001427:Bacterial Toxins; D004731:Endotoxins / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D006460:Hemolysin Proteins; D006801:Humans; D007938:Leukemia / Q000188:drug therapy*; D008565:Membrane Proteins / Q000378:metabolism; D008970:Molecular Weight; D013601:T-Lymphocytes / Q000187:drug effects*; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D008565:Membrane Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis