Biopolymers and cell. 1999; 15 (2): 163 - 167

Comparativs analysis of the spectrum of crystal proteins and Bacillus thuringiensis of new plasmids strains

I.A. Isakova, S. E, Rimar, L. N. Kuznetsova, V. A. Kordyum

The spectrum of insecticidal crystal proteins produced by 9 new B. thuringiensis strains isolated in Ukraine was studied. These strains demonstrated high toxicity to Lepidoptera and lower toxicity to Coleoptera (Colorado potato beettle larvae) in biological tests. It was shown that 5 strains produce high molecular weight proteins (137—164 kD), 3 strains produce 76.5 kD proteins, and one produce two proteins (96.5 kD and 77 kD). All the studied strains contain the spectrum of plasmids of both low molecular weight (less than 10 MD) and high molecular weight (more than 30 MD). The strains producing crystal proteins of similar molecular weight differ by plasmid composition.