Sequence of the gene encoding type F neurotoxin of Clostridium botulinum

Abstract

Primers designed to conserved regions of botulinum and tetanus clostridial toxins were used to amplify DNA fragments from non-proteolytic Clostridium botulinum type F (202F) DNA using polymerase chain reaction technology. The fragments were cloned and the complete nucleotide sequence of the gene encoding type F toxin determined. Analysis of the nucleotide sequence demonstrated the presence of an open frame encoding a protein of 1274 amino acids, similar to other botulinum neurotoxins. Upstream of the toxin gene is the end of an open reading frame which encodes the C-terminus of a protein with homology to non-toxic-non-hemagglutinin component of type C progenitor toxin.

Botulism Due to Clostridium baratii Type F Toxin

“…The heavy chain of C. baratii toxin F shows higher sequence similarity, 73.6 and 68.4%, with the heavy chains of C. botulinum toxins F and E, respectively (5). Since the heavy chains apparently determine the receptor function, the noted similar homologies between the heavy chains of F and E indicate a shared receptor.…”

“…Recently, there have been several studies on the genetic and structural relationships among clostridial neurotoxins (5,8,9,13). Sequence analysis has shown that there is high genetic homology between the toxins E produced by C. butyricum and C. botulinum but low relatedness between the genes coding for the toxins F of C. baratii and saccharolytic C. botulinum.…”

Multiplex PCR Assay for Detection and Identification of Clostridium botulinum Types A, B, E, and F in Food and Fecal Material

“…Based on published DNA sequences of the BoNT gene (2,8,9,27,33,34,35), four new primer pairs with each being specific for either C. botulinum type A, B, E, or F were designed ( Table 2). The primers were selected from the nonhomologous regions of the BoNT types A, B, E, and F gene by using the Primer 3 software (S. Rozen and H. J. Skaletsky, Primer 3, Whitehead Institute for Biomedical Research, Cambridge, Mass.…”

Engineering of botulinum neurotoxins as novel therapeutic tools

“…The abovementioned experimental hurdle was circumvented by devising an innovative technique for making BoNTs recombinantly in Escherichia coli after the genes for several BoNT serotypes had been cloned [13][14][15][16][17][18][19][20][21]. Prior to this, progress had been hampered by difficulties encountered when separately expressing the chains due to improper or incomplete folding, insolubility, and further problems after their reconstitution, particularly recovering the biological activities [22].…”