Bacillus thuringiensis serovar shandongiensis strain 89-T-34-22 produces multiple cytotoxic proteins with similar molecular masses against human cancer cells.
OBJECTIVE
To prove that Bacillus thuringiensis serovar shandongiensis strain 89-T-34-22 produces several novel cytotoxic proteins against human leukaemic T cells.


RESULTS
Parasporal inclusion protein was solubilized and processed by proteinase K and was separated by anion-exchange chromatography. Cytopathic effects of each fraction against MOLT-4 and Jurkat cells were monitored.


CONCLUSIONS
Existence of at least two novel cytotoxic proteins was suggested and N-terminal sequences of the newly identified proteins were determined to be QSTTDVIREY and X (Y or I) (P or I) NLANELA (X indicates uncertain amino acids). Molecular masses of the two proteins were approx. 27-28 kDa.


CONCLUSIONS
In this study, we demonstrated that the strain 89-T-34-22 produces at least two novel cytotoxic proteins with similar molecular masses against human cancer cells. This is the first strain of B. thuringiensis which produces multiple cytotoxic proteins against human cancer cells.
Okumura
S
S
Fukuoka Industrial Technology Center, Fukuoka, Japan. sokumura@fitc.pref.fukuoka.jp
Akao
T
T
Higuchi
K
K
Saitoh
H
H
Mizuki
E
E
Ohba
M
M
Inouye
K
K
D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D001413:Bacillus thuringiensis / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D003603:Cytotoxins / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D019169:Jurkat Cells; D015458:Leukemia, T-Cell; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000970:Antineoplastic Agents; D001426:Bacterial Proteins; D003603:Cytotoxins