title: A cryptic 19-kilobase plasmid associated with U.S. isolates of Yersinia pestis: a dimer of the 9.5-kilobase plasmid.
abstract: Yersinia pestis, the etiologic agent of plague, carries three prototypic plasmids with sizes of 110 kb (pFra, pTox), 70 kb (pLcr, pVW, pCad), and 9.5 kb (pPla, pPst). Studies suggest that geographic isolates of Y. pestis may be differentiated by plasmid profiles. Yersinia pestis isolated from the western United States harbor an additional plasmid, estimated to be approximately 19 kb in size. This cryptic plasmid was characterized by restriction endonuclease digestion, amplification and sequencing of the plasminogen activator gene segment, Southern blotting, and visualized by electron microscopy. Results revealed that this cryptic plasmid is a supercoiled DNA plasmid, 18.85+/-0.59 (mean+/-SD) kb in length, and is a dimer of the 9.5-kb plasmid. The genetic reason for the appearance of this form of the 9.5-kb plasmid in Y. pestis from Arizona, California, Colorado, New Mexico, and Texas is under study.
authors.affiliation: Division of Vector-Borne Infectious Diseases, National Center for Infectious Disease, Centers for Disease Control and Prevention, Fort Collins, Colorado 80522-2087, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Chu
authors.forename: X Q
authors.initials: XQ
authors.lastname: Dong
authors.forename: X
authors.initials: X
authors.lastname: Zhou
authors.forename: C F
authors.initials: CF
authors.lastname: Garon
mesh_terms: D000818:Animals; D001426:Bacterial Proteins; D001430:Bacteriocins / Q000096:biosynthesis / Q000235:genetics; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D019281:Dimerization; D005798:Genes, Bacterial; D005819:Genetic Markers; D006801:Humans; D008854:Microscopy, Electron; D010930:Plague / Q000382:microbiology; D010957:Plasmids / Q000737:chemistry* / Q000235:genetics* / Q000648:ultrastructure; D010960:Plasminogen Activators / Q000235:genetics; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D005423:Siphonaptera / Q000382:microbiology; D015206:Southwestern United States; D014774:Virulence / Q000235:genetics; D015010:Yersinia pestis / Q000235:genetics* / Q000302:isolation & purification* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins; D017931:DNA Primers; D005819:Genetic Markers; C011330:Pesticin; C078140:Pla protease, Yersinia pestis; D010960:Plasminogen Activators