title: Clostridium sporogenes isolates and their relationship to C. botulinum based on deoxyribonucleic acid reassociation.
abstract: Sixty-two isolates of Clostridium sporogenes from canned foods were examined for cultural properties, heat resistance and DNA-DNA homology to Clostridium botulinum type A190. Sporulation was observed in most of 21 umbonate and rhizoidal colony-forming strains (colony-type I strains), but not in most of the 41 strains with convex and circular or crenate colonies with a mat to semi-glossy surface (colony-type II strains). More than half of the latter strains showed much higher heat resistance than the rhizoidal colony-forming strains. The DNA isolated from colony-type II strains was 81% or more homologous to C. botulinum A190 DNA, forming duplexes which had thermostabilities similar to homologous duplexes of strain A190 DNA. Colony-type I strains differed from C. botulinum by 30 to 40% DNA homology and the DNA duplexes formed between these strains and strain A190 showed deltaT m(e) values of 7-0 degrees C when compared with the T m(e) of homologous DNA duplexes of strain A190.
mesh_terms: D002999:Clone Cells; D003013:Clostridium / Q000145:classification*; D003014:Clostridium botulinum / Q000145:classification; D004269:DNA, Bacterial / Q000032:analysis; D006358:Hot Temperature; D009695:Nucleic Acid Renaturation; D013171:Spores, Bacterial
chemical_list: D004269:DNA, Bacterial