title: Analysis of a DNA region from low-copy-number plasmid pYAN-1 of Sphingobium yanoikuyae responsible for plasmid stability.
abstract: We identified and analyzed a DNA region that is required for the stable maintenance of plasmids in the genus Sphingomonas. This DNA fragment, a 244 bp, is localized in the upstream region of the repA gene of low-copy-number small plasmid pYAN-1 (4896 bp) of Sphingobium yanoikuyae. It has four inverted repeats and one direct repeat for possible secondary structures. We were able to stabilize not only another unstable plasmid, pYAN-2, in the genus Sphingomonas, but also the unstable plasmid pSC101 without par locus in Escherichia coli. The copy-number levels between the unstable plasmid and the parental plasmid were similar, and these results suggest that the stabilization of unstable plasmids by this DNA region of pYAN-1 was not due to an increase in plasmid copy number. We concluded that the stabilization of the plasmid was due to a plasmid partition mechanism encoded by a DNA fragment of pYAN-1.
authors.affiliation: a United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology , Fuchu, Tokyo , Japan.
authors.forename: Hiroe
authors.initials: H
authors.lastname: Hayashi
authors.forename: Yasuroh
authors.initials: Y
authors.lastname: Kurusu
mesh_terms: D004261:DNA Replication / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D010957:Plasmids / Q000235:genetics*; D042301:Sphingomonadaceae / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial
keywords: non-coding DNA; partition; plasmid; sphingomonad