Table 2.

Cytocidal activity of purified inclusions from B. thuringiensis strains

OrganismInclusion componentEC50(μg ml−1)a
MOLT-4 cellsNormal T cellsHeLa cells
84-HS-1-11Wild type36.6 (32.8–40.9)>1308.7 (8.1–9.3)
BFR1(pLEUK3.4)Parasporin (Cry31Aa1)14.6 (13.5–15.7)>1305.8 (5.4–6.1)
B. thuringiensis serovar IsraelensisCyt1Ab 2.4 (2.1–2.6)126.2 (101.7–160.3)8.6 (7.9–9.3)
  • a Values were calculated on the basis of 24-h cell mortalities using a log-probit program. The fiducial limit at the 95% level is given parentheses.

  • b Dipteran-specific Cry proteins (Cry4A, Cry4B, and Cry11A) coexist in inclusions (3).