Ubiquity of parasporin-1 producers in Bacillus thuringiensis natural populations of Japan

Naturwissenschaften. 2007 Jan;94(1):34-8. doi: 10.1007/s00114-006-0153-7. Epub 2006 Sep 7.


Parasporin, a Bacillus thuringiensis parasporal protein, is unique in having a strong cytocidal activity preferential for human cancer cells. In this study, we characterized parasporin activities associated with three novel geographical isolates of B. thuringiensis. Parasporal inclusion proteins of the three isolates were highly toxic to human uterus cervix cancer cells (HeLa), but not to non-cancer uterine smooth muscle cells (UtSMC). Inclusions of the isolates lacked insect toxicity and hemolytic activity against sheep erythrocytes. Ouchterlony immunodiffusion tests revealed that the proteins of the three isolates are immunologically closely related to parasporin-1 (Cry31A), but dissimilar to the three other existing parasporin groups. Our results provide evidence that the parasporin-1-producing organism is a common member in B. thuringiensis populations occurring in natural environments of Japan.

MeSH terms

  • Agglutination Tests
  • Antineoplastic Agents / therapeutic use
  • Antineoplastic Agents / toxicity
  • Bacillus thuringiensis / physiology*
  • Bacillus thuringiensis / ultrastructure
  • Bacterial Proteins / biosynthesis
  • Bacterial Proteins / therapeutic use
  • Bacterial Proteins / toxicity
  • Endotoxins / biosynthesis*
  • Endotoxins / therapeutic use
  • Endotoxins / toxicity
  • HeLa Cells / drug effects
  • Humans
  • Japan
  • Neoplasms / drug therapy


  • Antineoplastic Agents
  • Bacterial Proteins
  • Endotoxins
  • parasporin