Noninsecticidal parasporal proteins of a Bacillus thuringiensis serovar shandongiensis isolate exhibit a preferential cytotoxicity against human leukemic T cells.
A Bacillus thuringiensis isolate, 89-T-34-22, belonging to the serovar shandongiensis (H22) produced noninsecticidal and nonhemolytic proteins crystallizing into irregular-shaped parasporal inclusions. The proteins showed in vitro cytotoxicity to human cells, including cancer cells, only when activated by protease treatment. The human leukemic T (MOLT-4) cells were > 100 times more susceptible than HeLa and normal T cells to the proteins of 89-T-34-22. The cytotoxicity was dose dependent and the median effective concentration for the MOLT-4 was 3.5 microg/ml. The cytopathy induced by the 89-T-34-22 proteins was characterized by remarkable condensation of the nucleus and cell-ballooning. Five major parasporal proteins of 89-T-34-22, with molecular masses in the range of 16-160 kDa, shared no similarity with the previously reported proteins in terms of the N-terminal sequence.
Lee
D W
DW
Biotechnology and Food Research Institute, Fukuoka Industrial Technology Center, Kurume, Japan.
Akao
T
T
Yamashita
S
S
Katayama
H
H
Maeda
M
M
Saitoh
H
H
Mizuki
E
E
Ohba
M
M
D000595:Amino Acid Sequence; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001413:Bacillus thuringiensis / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006367:HeLa Cells; D006801:Humans; D002479:Inclusion Bodies / Q000737:chemistry; D015458:Leukemia, T-Cell / Q000188:drug therapy*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013171:Spores, Bacterial / Q000737:chemistry; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D001426:Bacterial Proteins