TY - JOUR
T1 - Specificity determinants of conjugative DNA processing in the Enterococcus faecalis plasmid pCF10 and the Lactococcus lactis plasmid pRS01
AU - Chen, Yuqing
AU - Staddon, Jack H.
AU - Dunny, Gary M
PY - 2007/3
Y1 - 2007/3
N2 - The DNA-processing region of the Enterococcus faecalis pheromone-responsive plasmid pCF10 is highly similar to that of the otherwise unrelated plasmid pRS01 from Lactococcus lactis. A transfer-proficient pRS01 derivative was unable to mobilize plasmids containing the pCF10 origin of transfer, oriT. In contrast, pRS01 oriT-containing plasmids could be mobilized by pCF10 at a low frequency. Relaxases PcfG and LtrB were both capable of binding to single-stranded oriT DNAs; LtrB was highly specific for its cognate oriT, whereas PcfG could recognize both pCF10 and pRS01 oriT. However, pcfG was unable to complement an ltrB insertion mutation. Genetic analysis showed that pcfF of pCF10 and ltrF of pRS01 are also essential for plasmid transfer. Purified PcfF and LtrF possess double-stranded DNA binding activities for the inverted repeat within either oriT sequence. PcfG and LtrB were recruited into their cognate F-oriT DNA complex through direct interactions with their cognate accessory protein. PcfG also could interact with LtrF when pCF10 oriT was present. In vivo cross-complementation analysis showed that ltrF partially restored the pCF10ΔpcfF mutant transfer ability when provided in trans, whereas pcfF failed to complement an ltrF mutation. Specificity of conjugative DNA processing in these plasmids involves both DNA-protein and protein-protein interactions.
AB - The DNA-processing region of the Enterococcus faecalis pheromone-responsive plasmid pCF10 is highly similar to that of the otherwise unrelated plasmid pRS01 from Lactococcus lactis. A transfer-proficient pRS01 derivative was unable to mobilize plasmids containing the pCF10 origin of transfer, oriT. In contrast, pRS01 oriT-containing plasmids could be mobilized by pCF10 at a low frequency. Relaxases PcfG and LtrB were both capable of binding to single-stranded oriT DNAs; LtrB was highly specific for its cognate oriT, whereas PcfG could recognize both pCF10 and pRS01 oriT. However, pcfG was unable to complement an ltrB insertion mutation. Genetic analysis showed that pcfF of pCF10 and ltrF of pRS01 are also essential for plasmid transfer. Purified PcfF and LtrF possess double-stranded DNA binding activities for the inverted repeat within either oriT sequence. PcfG and LtrB were recruited into their cognate F-oriT DNA complex through direct interactions with their cognate accessory protein. PcfG also could interact with LtrF when pCF10 oriT was present. In vivo cross-complementation analysis showed that ltrF partially restored the pCF10ΔpcfF mutant transfer ability when provided in trans, whereas pcfF failed to complement an ltrF mutation. Specificity of conjugative DNA processing in these plasmids involves both DNA-protein and protein-protein interactions.
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U2 - 10.1111/j.1365-2958.2007.05610.x
DO - 10.1111/j.1365-2958.2007.05610.x
M3 - Article
C2 - 17302827
AN - SCOPUS:33847005432
SN - 0950-382X
VL - 63
SP - 1549
EP - 1564
JO - Molecular Microbiology
JF - Molecular Microbiology
IS - 5
ER -