[Proteins of Bacillus thuringiensis delta-endotoxin crystals].
Pure crystals (at least 99% purification) of sigma-endotoxin were isolated from Bac. thuringiensis var. galleriae. The complete dissolution of crystals might be achieved by the increase of pH up to 12 and higher or by a combined action of S = S-reducing and denaturing agents. Electrophoresis of the solubilized crystal proteins in 5% polyacrylamide gels containing 0,1% sodium dodecyl sulfate and 8 M urea reveals two major bands corresponding to molecular weights of 120000--140000 (65%) and 65000 (8-10%), and some minor components whose molecular weights varied from 65000 to 340000. Urea (3--8 M) causes to partial dissolution of the crystals; the component with molecular weight of 65000 is mainly found in the solution (component A). In dithioerythritol extracts at pH 9 the major component of the crystal is the protein with molecular weight 120000--140000 (component B). The crystals, alkali-soluble components and proteins isolated from crystals by selective extraction (3--8 M urea or 0.01 M dithioerythrytol, pH 9) were found toxic for the larvae of Galleria mellonella.
D000818:Animals; D001413:Bacillus thuringiensis / Q000032:analysis*; D001426:Bacterial Proteins / Q000302:isolation & purification* / Q000633:toxicity; D001427:Bacterial Toxins / Q000302:isolation & purification* / Q000633:toxicity; D003460:Crystallization; D004731:Endotoxins / Q000302:isolation & purification* / Q000633:toxicity; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000187:drug effects; D008970:Molecular Weight; D009036:Moths / Q000187:drug effects; D012995:Solubility
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins
Belki kristallov delta-endotoksina Bac. thuringiensis.