Type II restriction modification system in Ureaplasma parvum OMC-P162 strain

PLoS One. 2018 Oct 16;13(10):e0205328. doi: 10.1371/journal.pone.0205328. eCollection 2018.

Abstract

Ureaplasma parvum serovar 3 strain, OMC-P162, was isolated from the human placenta of a preterm delivery at 26 weeks' gestation. In this study, we sequenced the complete genome of OMC-P162 and compared it with other serovar 3 strains isolated from patients with different clinical conditions. Ten unique genes in OMC-P162, five of which encoded for hypothetical proteins, were identified. Of these, genes UPV_229 and UPV_230 formed an operon whose open reading frames were predicted to code for a DNA methyltransferase and a hypothetical protein, respectively. DNA modification analysis of the OMC-P162 genome identified N4-methylcytosine (m4C) and N6-methyladenine (m6A), but not 5-methylocytosine (m5C). UPV230 recombinant protein displayed endonuclease activity and recognized the CATG sequence, resulting in a blunt cut between A and T. This restriction enzyme activity was identical to that of the cultivated OMC-P162 strain, suggesting that this restriction enzyme was naturally expressed in OMC-P162. We designated this enzyme as UpaP162. Treatment of pT7Blue plasmid with recombinant protein UPV229 completely blocked UpaP162 restriction enzyme activity. These results suggest that the UPV_229 and UPV_230 genes act as a type II restriction-modification system in Ureaplasma OMC-P162.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Restriction-Modification Enzymes / genetics*
  • DNA Restriction-Modification Enzymes / isolation & purification
  • Female
  • Humans
  • Methyltransferases / genetics*
  • Methyltransferases / isolation & purification
  • Obstetric Labor, Premature / genetics*
  • Obstetric Labor, Premature / microbiology
  • Open Reading Frames / genetics
  • Operon / genetics
  • Placenta / microbiology
  • Plasmids / genetics
  • Pregnancy
  • Ureaplasma / genetics*
  • Ureaplasma / pathogenicity

Substances

  • DNA Restriction-Modification Enzymes
  • Methyltransferases

Grants and funding

This work was supported by research grants from the JSPS KAKENHI, Grant Numbers JP17H04237 (I. Y.) and JP18K16788 (M. Y.) https://www.jsps.go.jp/english/index.html; the Japan Agency for Medical Research and Development (AMED), JP17fk0108210 (I. Y.) https://www.amed.go.jp/en/index.html; and the SENTAN, Japan Science and Technology Agency, 14533524 (K. Y. and I. Y.) https://www.jst.go.jp/sentan/en/index.html.