title: CTnscr94, a conjugative transposon found in enterobacteria.
abstract: Conjugational transposons are important for horizontal gene transfer in gram-positive and gram-negative bacteria, but have not been reported yet for enteric bacteria. Salmonella senftenberg 5494-57 has previously been shown to transfer by conjugation genes for a sucrose fermentation pathway which were located on a DNA element called scr-94. We report here that the corresponding scr genes for a phosphoenolpyruvate-dependent sucrose:phosphotransferase system and a sucrose metabolic pathway are located on a large (ca. 100 kb) conjugative transposon renamed CTnscr94. The self-transmissible element integrates at two specific attachment sites in a RecA-independent way into the chromosome of Escherichia coli K-12 strains. One site was identified within pheV, the structural gene for a tRNA(Phe). Sequencing of both ends of CTnscr94 revealed the presence of the 3' part of pheV on one end such that after integration of the element, a complete pheV gene is retained. CTnscr94 represents, to our knowledge, the first conjugational transposon found in enteric bacteria.
authors.affiliation: Arbeitsgruppe Genetik, Fachbereich Biologie/Chemie, Universität Osnabrück, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Hochhut
authors.forename: K
authors.initials: K
authors.lastname: Jahreis
authors.forename: J W
authors.initials: JW
authors.lastname: Lengeler
authors.forename: K
authors.initials: K
authors.lastname: Schmid
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial / Q000235:genetics; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics*; D008969:Molecular Sequence Data; D011938:Rec A Recombinases / Q000378:metabolism; D015183:Restriction Mapping; D013395:Sucrose / Q000378:metabolism*
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D013395:Sucrose; D011938:Rec A Recombinases