Characterization of bacteriophage nucleic acids obtained from Clostridium botulinum types C and D.
Nontoxigenic strains of Clostridium botulinum types C and D are converted to toxigenic strains by infection with specific Tox+ bacteriophages. The nucleic acids were extracted from five converting phages, c-st, c-468, c-203, c-d6f, and d-1873, and one nonconverting phage, c-n71, and treated with nucleases. The nucleic acids isolated were not digested by RNase A, but were digested by DNase I and exonuclease III, indicating that they were double-stranded DNA. On the basis of the restriction endonuclease digestion patterns on 0.8% agarose gel electrophoresis, the length of c-st, c-n71, c-468, and c-d6f phage DNAs was estimated to be about 110 kilobase pairs and that of c-203 and d-1873 was about 150 kilobase pairs. The digestion patterns of c-st, c-468, and c-n71 phage DNAs by PstI and HindIII were very similar. High homology was observed in the dot hybridization test. For other phages and nucleases, a good similarity was not observed. Only a little similarity was observed between c-203 and c-d6f phages. The existence of the structural genes for the toxin in both c-st and c-n71 phages was confirmed by the hybridization test with these phage DNAs and the oligonucleotide probe which represented the DNA sequence predicted for the N-terminal amino acids (2 to 17) of C. botulinum type C toxin. The loss of the converting ability of c-n71 phage may be caused not by the deletion of the tox+ gene but rather by the base mutation in c-st phage DNA.
Fujii
N
N
Department of Microbiology, Sapporo Medical College, Japan.
Oguma
K
K
Yokosawa
N
N
Kimura
K
K
Tsuzuki
K
K
D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000235:genetics*; D001905:Botulinum Toxins / Q000032:analysis / Q000235:genetics; D003014:Clostridium botulinum / Q000235:genetics*; D004279:DNA, Viral / Q000032:analysis*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization
D004279:DNA, Viral; D001905:Botulinum Toxins