title: Domain organization of Bacillus thuringiensis CryIIIA delta-endotoxin studied by denaturation in guanidine hydrochloride solutions and limited proteolysis.
abstract: Denaturation of Bacillus thuringiensis CryIIIA delta-endotoxin--an insecticidal protein, active against Coleoptera larvae--in concentrated guanidine hydrochloride solutions was pursued by fluorescence and circular dichroism spectroscopy and limited proteolysis. It was found that the protein consists of two fragments that differ by their stability to denaturation by guanidine hydrochloride at pH 3. The less stable fragment corresponds to the N-terminal alpha-helical domain limited by Leu-279; the more stable one starts with Ile-280, contains about 330 amino acid residues, and corresponds to the molecule C-terminal moiety that consist of its two beta-structural domains forming a superdomain.
authors.affiliation: Laboratory of Protein Chemistry, Institute of Genetics and Selection of Industrial Microorganisms, Moscow, Russia.
authors.forename: P
authors.initials: P
authors.lastname: Ort
authors.forename: I A
authors.initials: IA
authors.lastname: Zalunin
authors.forename: V S
authors.initials: VS
authors.lastname: Gasparov
authors.forename: G G
authors.initials: GG
authors.lastname: Chestukhina
authors.forename: V M
authors.initials: VM
authors.lastname: Stepanov
mesh_terms: D000595:Amino Acid Sequence; D001413:Bacillus thuringiensis / Q000737:chemistry*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry*; D001427:Bacterial Toxins; D002942:Circular Dichroism; D004731:Endotoxins / Q000737:chemistry*; D019791:Guanidine; D006146:Guanidines; D006460:Hemolysin Proteins; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010434:Pepsin A / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D013050:Spectrometry, Fluorescence
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006146:Guanidines; D006460:Hemolysin Proteins; D010446:Peptide Fragments; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D010434:Pepsin A; D019791:Guanidine