title: Cloning and characterization of a novel Bacillus thuringiensis cytolytic delta-endotoxin.
abstract: A gene encoding a major entomocidal polypeptide from Bacillus thuringiensis subspecies kyushuensis delta-endotoxin crystals (CytB) was cloned into Escherichia coli and sequenced. The deduced amino acid sequence gave a predicted molecular mass of 29,236 Da and showed 39% identity and 70% similarity with the 27,371 Da CytA protein from Bacillus thuringiensis subspecies israelensis. The larger size of CytB compared to CytA appears to be due to additional sequence in CytB after the CytA C-terminus. Unlike CytA, CytB was freely expressed in Escherichia coli and formed cytoplasmic inclusions without the need for a "helper" protein. Electron microscopic observation of CytB inclusions revealed them to be generally amorphous, but examples possessing some lattice structure were seen.
authors.affiliation: Department of Biochemistry, University of Cambridge, England.
authors.forename: P A
authors.initials: PA
authors.lastname: Koni
authors.forename: D J
authors.initials: DJ
authors.lastname: Ellar
mesh_terms: D000595:Amino Acid Sequence; D001413:Bacillus thuringiensis / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D004731:Endotoxins / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli; D006460:Hemolysin Proteins; D007306:Insecticides / Q000378:metabolism*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis