@article{mbs:/content/journal/micro/10.1099/00221287-139-1-79, author = "Fujii, Nobuhiro and Kimura, Kouichi and Yokosawa, Noriko and Yashiki, Teruo and Tsuzuki, Kayo and Oguma, Keiji", title = "The complete nucleotide sequence of the gene encoding the nontoxic component of Clostridium botulinum type E progenitor toxin", journal= "Microbiology", year = "1993", volume = "139", number = "1", pages = "79-86", doi = "https://doi.org/10.1099/00221287-139-1-79", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-139-1-79", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "We have analysed the genes borne on a 6ยท0 kb Hin dIII fragment cloned from the chromosome of Clostridium botulinum type E strain Mashike. This fragment, cloned within plasmid pU9EMH, contains part of the structural gene for botulinum toxin type E neurotoxin as well as the entire structural gene for a nontoxic component of botulinum type E progenitor neurotoxin gene, ent-120. ent-120 is transcribed in the same direction as the neurotoxin gene and consists of one open reading frame encoding 1162 amino acid residues. Western blotting with anti-nontoxic component sera demonstrates that ent-120 encodes a protein of 120 kDa which forms part of the nontoxic component. ent-120 is homologous to an analogous gene found in botulinum type C strains (69.3% identity at the nucleotide level and 56.1% at the amino acid level). Two stretches of amino acids at the N-terminus of the ent-120 protein are highly homologous to amino acid sequences within the type E neurotoxin. The stop codon of the ent-120 gene is situated 27 nucleotides upstream from the start codon of the neurotoxin gene.", }