Isolation and transposition properties of ISBlo11, an active insertion sequence belonging to the IS3 family, from Bifidobacterium longum 105-A.
Transposon mutagenesis systems are still under development in bifidobacteria, partly because intrinsic active insertion sequences are not well characterized in bifidobacteria. Here, we isolated an active insertion sequence, ISBlo11, from Bifidobacterium longum 105-A using a sacB-based counterselection system, which is generally used to screen for active insertion sequences from bacterial genomes. ISBlo11 is 1432 bp long and belongs to the IS3 family. It has a single ORF encoding a transposase and 25-bp inverted repeats at its termini. Full-length copies of ISBlo11 are specifically conserved among certain B. longum genomes and exist in different sites. Transposition analysis of an artificial ISBlo11 transposon using an Escherichia coli conjugation system revealed that ISBlo11 has adequate transposition activity, comparable to the reported activity of IS629, another IS3 family element initially isolated from Shigella sonnei. ISBlo11 also showed low transposition selectivity for non-conserved 3- or 4-bp target sequences. These characteristics of ISBlo11 seem suitable for the development of a new transposon mutagenesis system in bifidobacteria.
Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Mikiyasu
M
Sakanaka
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.
Satoru
S
Fukiya
Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Ryoko
R
Kobayashi
Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Arisa
A
Abe
Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Yosuke
Y
Hirayama
Department of Molecular Genetics, Kyoto Pharmaceutical University, 5, Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
Yasunobu
Y
Kano
Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Atsushi
A
Yokota
D000595:Amino Acid Sequence; D001483:Base Sequence; D001644:Bifidobacterium / Q000235:genetics*; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D016680:Genome, Bacterial; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames
D004251:DNA Transposable Elements; D004269:DNA, Bacterial
IS element; mobile element; random mutagenesis; transposable element; transposon mutagenesis