Protease-resistant core form of Bacillus thuringiensis Cry1Ie: monomeric and oligomeric forms in solution.
Cry1Ie is encoded by cry1Ie, a gene that is silent in Bacillus thuringiensis strains but can be over-expressed in Escherichia coli. A protease-resistant core form of Cry1Ie with a molecular weight of approx. 55 kDa was found among the products of trypsin digestion. The oligomer and monomer of the protease-resistant core form were purified separately. The oligomer fraction contained a small quantity of dimer and a large amount of aggregates larger than tetramers. The 50% lethal concentrations (LC(50)) of the full-length Cry1Ie and both the monomer and oligomer fractions of the protease-resistant core form against Plutella xylostella were 14, 21 and 1400 microg/ml, respectively.
Guo
Shuyuan
S
School of Life Science and Technology, Beijing Institute of Technology, 100081, Beijing, China.
Zhang
Yancai
Y
Song
Fuping
F
Zhang
Jie
J
Huang
Dafang
D
D000818:Animals; D001413:Bacillus thuringiensis / Q000737:chemistry*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D001681:Biological Assay; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004731:Endotoxins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D007915:Lepidoptera / Q000187:drug effects; D020836:Protein Structure, Quaternary; D012996:Solutions; D014357:Trypsin / Q000378:metabolism*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D012996:Solutions; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D014357:Trypsin