title: Characterization of an insertion sequence-like element, ISBlo15, identified in a size-increased cryptic plasmid pBK283 in Bifidobacterium longum BK28.
abstract: The characteristics of mobile genetic elements in bifidobacteria are not well understood. We characterized an insertion sequence-like element of the IS200/IS605 family found in a size-increased cryptic plasmid in Bifidobacterium longum. During a plasmid profile analysis of B. longum BK strains, we encountered a 6.5-kbp cryptic plasmid pBK283 in B. longum BK28, the size of which has not been identified in bifidobacteria. Nucleotide sequence analysis indicated that an insertion sequence-like element was inserted into the 5.0-kbp pKJ50-like plasmid and resulted in a size increase of pBK283. The element, named ISBlo15, was 1593 bp in length and contained a single ORF encoding a putative transposase, which is similar to the transposase OrfB encoded by IS200/IS605 family elements. Several sequence characteristics, including conserved transposase motifs in OrfB and terminal palindromic sequences that differ from the typical terminal inverted repeats, strongly suggested that ISBlo15 is a member of the IS200/IS605 family. Sequences similar to ISBlo15 were widely distributed among the nine Bifidobacterium species tested, and those of highly homologous sequences were detected only in Bifidobacterium gallicum JCM8224(T).
authors.affiliation: Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan. s-fukiya@chem.agr.hokudai.ac.jp
authors.forename: Satoru
authors.initials: S
authors.lastname: Fukiya
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Kano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yokota
mesh_terms: D001483:Base Sequence; D001644:Bifidobacterium / Q000145:classification* / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics*; D013045:Species Specificity
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial