title: Generation of an erythromycin-sensitive derivative of Clostridium difficile strain 630 (630Deltaerm) and demonstration that the conjugative transposon Tn916DeltaE enters the genome of this strain at multiple sites.
abstract: Erythromycin resistance in Clostridium difficile strain 630 is conferred by a genetic element termed Tn5398 which contains two erm(B) genes: erm1(B) and erm2(B). An erythromycin-sensitive derivative of strain 630 (designated 630Deltaerm) was generated by spontaneous mutation after continuous subculture for 30 days. This strain had lost the erm2(B) gene from within Tn5398 but retained erm1(B). However, the strain could revert to erythromycin resistance at a frequency of 2.79 x 10(-8), although it still contained the deletion of erm2(B). The availability of C. difficile 630Deltaerm allowed the behaviour of Tn916DeltaE to be investigated in this strain. This element entered the genome at multiple sites indicating that it could be useful as an insertional mutagen.
authors.affiliation: Division of Microbial Diseases, Eastman Dental Institute for Oral Health Care Sciences, University College London, 256 Gray's Inn Road, London WC1X 8LD, UK.
authors.forename: Haitham A
authors.initials: HA
authors.lastname: Hussain
authors.affiliation: Division of Microbial Diseases, Eastman Dental Institute for Oral Health Care Sciences, University College London, 256 Gray's Inn Road, London WC1X 8LD, UK.
authors.forename: Adam P
authors.initials: AP
authors.lastname: Roberts
authors.affiliation: Division of Microbial Diseases, Eastman Dental Institute for Oral Health Care Sciences, University College London, 256 Gray's Inn Road, London WC1X 8LD, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Mullany
mesh_terms: D015139:Blotting, Southern; D016360:Clostridioides difficile / Q000187:drug effects* / Q000235:genetics; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000032:analysis; D004917:Erythromycin / Q000494:pharmacology*; D018014:Gene Transfer Techniques; D016680:Genome, Bacterial; D008826:Microbial Sensitivity Tests; D014169:Transformation, Bacterial
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004917:Erythromycin