title: Evidence that the clindamycin-erythromycin resistance gene of Bacteroides plasmid pBF4 is on a transposable element.
abstract: We constructed a shuttle vector, pE5-2, which can replicate in both Bacteroides spp. and Escherichia coli. pE5-2 contains a cryptic Bacteroides plasmid (pB8-51), a 3.8-kilobase (kb) EcoRI-D fragment from the 41-kb Bacteroides fragilis plasmid pBF4, and RSF1010, an IncQ E. coli plasmid. pE5-2 was mobilized by R751, an IncP E. coli plasmid, between E. coli strains with a frequency of 5 X 10(-2) to 3.8 X 10(-1) transconjugants per recipient. R751 also mobilized pE5-2 from E. coli donors to Bacteroides uniformis 0061RT and Bacteroides thetaiotaomicron 5482 with a frequency of 0.9 X 10(-6) to 2.5 X 10(-6). The Bacteroides transconjugants contained only pE5-2 and were resistant to clindamycin and erythromycin. Thus, the gene for clindamycin and erythromycin resistance must be located within the Eco RI-D fragment of BF4. A second recombinant plasmid, pSS-2, which contained 33 kb of pBF4 (including the EcoRI-D fragment and contiguous regions) could also be mobilized by R751 between E. coli strains. In some transconjugants, a 5.5-kb (+/- 0.3 kb) segment of the pBF4 portion of pSS2 was inserted into one of several sites on R751. In some other transconjugants this same 5.5-kb segment was integrated into the E. coli chromosome. This segment could transfer a second time onto R751. Transfer was RecA independent. The transferred segment included the entire EcoRI-D fragment, and thus the clindamycin-erythromycin resistance determinant, from pBF4.
authors.forename: N B
authors.initials: NB
authors.lastname: Shoemaker
authors.forename: E P
authors.initials: EP
authors.lastname: Guthrie
authors.forename: A A
authors.initials: AA
authors.lastname: Salyers
authors.forename: J F
authors.initials: JF
authors.lastname: Gardner
mesh_terms: D001439:Bacteroides / Q000235:genetics*; D002981:Clindamycin / Q000494:pharmacology*; D003227:Conjugation, Genetic; D004262:DNA Restriction Enzymes; D004251:DNA Transposable Elements; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000494:pharmacology*; D005796:Genes; D005798:Genes, Bacterial; D011815:R Factors
chemical_list: D004251:DNA Transposable Elements; D002981:Clindamycin; D004917:Erythromycin; D004262:DNA Restriction Enzymes