Characterization of a cryptic plasmid, pSM103mini, from polyethylene-glycol degrading sphingopyxis macrogoltabida strain 103

Akiwo Tani, Akiyuki Tanaka, Toshiyuki Minami, Kazuhide Kimbara, Fusako Kawai

Research output: Contribution to journalArticle

4 Citations (Scopus)


A cryptic plasmid, pSM103mini, was found in polyethylene-glycol degrading bacterium Sphingopyxis macrogoltabida, strain 103. The plasmid was 4,328-bp long and its GC content was 57.5%. It contained four open reading frames, but only two of them showed significant similarity to reported proteins. ORF3 and ORF4 were assumed to encode resolvase and replication protein (RepA) respectively. Downstream of ORF4 we found complex repeat sequences. These together with ORF3 and 4 were necessary and sufficient for plasmid maintenance in strain 103, as analyzed by constructing deletion plasmids. The pHSG398-fused plasmid (pHSG-SM103mini) functioned as a shuttle vector between strain 103 and Escherichia coli. The plasmid constructed was maintained in strain 103 and its close relative, S. macrogoltabida strain 203, but not efficiently in PEG-degrading S. terrae.

Original languageEnglish
Pages (from-to)295-298
Number of pages4
JournalBioscience, Biotechnology and Biochemistry
Issue number2
Publication statusPublished - 2011



  • Cryptic plasmid
  • Polyethylene-glycol
  • Shuttle plasmid
  • Sphingomonads
  • Sphingopyxis macrogoltabida

ASJC Scopus subject areas

  • Biotechnology
  • Biochemistry
  • Molecular Biology
  • Applied Microbiology and Biotechnology
  • Analytical Chemistry
  • Organic Chemistry

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