Open AccessSmall cryptic plasmids of Streptococcus pneumoniae belong to the pC194/pUB110 family of rolling circle plasmids
Author(s) -
Schuster Cordelia,
Linden Mark,
Hakenbeck Regine
Publication year - 1998
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1998.tb13119.x
Subject(s) - plasmid , rolling circle replication , streptococcus pneumoniae , streptococcaceae , genetics , microbiology and biotechnology , biology , bacteria , gene , dna replication
Abstract The DNA sequences of two related plasmids pPR1 and pPR3 described previously in Streptococcus pneumoniae isolates from Germany and Spain were now determined. Both plasmids belong to a family of rolling circle (RC) plasmids found in a variety of bacteria. Their GC content with 32% is lower than that of the S. pneumoniae chromosomal DNA. The plasmid pPR3 has a molecular size of 3160 bp with four putative open reading frames, whereas pPR1 contained a deletion of 313 bp that included the 5′‐part of ORF2 and upstream regions and differed by three bp from pPR3. The predicted protein of ORF1 showed high similarity to replication proteins of RC plasmids with 74% identical amino acids to RepA of Streptococcus thermophilus plasmids. Sequences similar to the plus origin of replication of ssDNA plasmids were present in both plasmids. They also contained a 152‐bp region with over 83% identity to the minus origin of replication of the Streptococcus agalacticae plasmid pMV158.