Active segregation by the Bacillus subtilis partitioning system in Escherichia coli.
Bacterial genes required for proper partitioning consist of two transacting genes that encode proteins and a cis-acting gene that functions like a centromere. Plasmids actively partitioning by means of these genes migrate from midcell to the cell quarters and are tethered to these sites until the cells divide. Previously the partitioning genes were mainly found on plasmids and phages in Escherichia coli. However, progress in genome sequencing reveals that partitioning genes are ubiquitous in many bacterial plasmids and chromosomes. Each homologue of the two transacting genes belongs to a family, ParA or ParB. Moreover, phylogenic analysis of members of the ParA and ParB families indicates that each member falls into a chromosomal group or an extrachromosomal group. It is known that the parAB genes in the chromosomal group are located on relatively conserved chromosomal regions in several bacterial species. This suggests that the parAB genes were transferred from a chromosome to plasmids and phages, so the genes have diverged among bacterial species. To support this possibility, we show that the Bacillus subtilis Soj and Spo0J members of the ParAB families are responsible for the specific localization of plasmids at cell quarters in E. coli and can function as partition proteins. Host factors to tether actively partitioning plasmids at subcellular sites may be conserved in Gram-negative and Gram-positive bacteria so that phages and plasmids with the ParAB partitioning system can be stably inherited in host cells across bacterial species.
Yamaichi
Y
Y
Division of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, 4-24-1, Kuhonji, Japan.
Niki
H
H
D000251:Adenosine Triphosphatases / Q000145:classification / Q000378:metabolism; D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids; D017386:Sequence Homology, Amino Acid; D012808:Sigma Factor; D014157:Transcription Factors
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D012808:Sigma Factor; C060972:SopB protein, Bacteria; C489223:SopB protein, E coli; D014157:Transcription Factors; C052883:chromosome partition proteins, bacterial; C092468:spoIIR protein, Bacillus subtilis; C030069:spore-specific proteins, Bacillus; C060971:SopA protein, Bacteria; D000251:Adenosine Triphosphatases; C072069:MinD protein, E coli