title: Botulinum neurotoxin type E fragmented with endoproteinase Lys-C reveals the site trypsin nicks and homology with tetanus neurotoxin.
abstract: Botulinum neurotoxin type E, a 150 kDa single chain protein, cleaved with endoproteinase Lys-C yielded 113, 73, and 50 kDa fragments. The N-terminal sequence of the 113 kDa fragment, Gly-Ile-Arg-Lys-Ser-Ile-Cys-Ile, overlaps the N-terminal sequence, Lys-Ser-Ile-Cys-Ile, of the 103 kDa heavy chain produced by nicking the neurotoxin with trypsin. The -Arg-Lys- bond is therefore the site on the single chain type E NT where trypsin nicks generating the 50 kDa light and 103 kDa heavy chains of the dichain NT. The sequence of the first 50 N-terminal residues of the 73 kDa fragment were determined. This fragment is a segment of the heavy chain; 50% of the 50 residues are present in identical positions in a similar segment of the heavy chain of tetanus neurotoxin.
authors.affiliation: Food Research Institute, University of Wisconsin, Madison 53706.
authors.forename: J A
authors.initials: JA
authors.lastname: Giménez
authors.forename: B R
authors.initials: BR
authors.lastname: DasGupta
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D001905:Botulinum Toxins; D003014:Clostridium botulinum / Q000235:genetics; D010450:Endopeptidases / Q000378:metabolism; D008666:Metalloendopeptidases; D008969:Molecular Sequence Data; D011489:Protein Denaturation; D012689:Sequence Homology, Nucleic Acid; D013744:Tetanus Toxin; D014357:Trypsin
chemical_list: D013744:Tetanus Toxin; D010450:Endopeptidases; D014357:Trypsin; D008666:Metalloendopeptidases; C039830:peptidyl-Lys metalloendopeptidase; D001905:Botulinum Toxins