Archaeal Plasmids

作者：Wolinowska Renata^*

来源：Postepy Mikrobiologii, 2008, 47(4): 457-463.

• Archaea
• chromosomal integration
• conjugative plasmids
• cryptic plasmids

Numerous plasmids can be found in the cells of Archaea, most of them have cryptic phenotypes. Among cryptic plasmids isolated from Crenarchaeota, a pRN1 family has been identified. These plasmids encode a unique replication protein, harbouring both primase and DNA polymerase activity. Plasmid pSSVx of that family may be packaged into capsids of fusellovirus, due to the presence of two viral genes in its structure. The investigated conjugative plasmids were found in Sulfolobus species. Conjugation differs from that known for bacterial cells. Both in cryptic and conjugative plasmids, integrase gene, enabling specific plasmid integration into chromosomal DNA, may be found. In some of these integrases, attachment site is placed inside the open reading frame encoding the integrase. Integrases found in cryptic plasmids of the pRN1 family are homologous to integrases of Archaea viruses. In cells of halophilic and methanogenic Archaea, big plasmids and megaplasmids have been found that carry genes necessary for cell activity.

• 出版日期2008