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Mechanism of staphylococcal multiresistance plasmid replication origin assembly by the RepA protein.
- Source :
-
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2014 Jun 24; Vol. 111 (25), pp. 9121-6. Date of Electronic Publication: 2014 Jun 09. - Publication Year :
- 2014
-
Abstract
- The staphylococcal multiresistance plasmids are key contributors to the alarming rise in bacterial multidrug resistance. A conserved replication initiator, RepA, encoded on these plasmids is essential for their propagation. RepA proteins consist of flexibly linked N-terminal (NTD) and C-terminal (CTD) domains. Despite their essential role in replication, the molecular basis for RepA function is unknown. Here we describe a complete structural and functional dissection of RepA proteins. Unexpectedly, both the RepA NTD and CTD show similarity to the corresponding domains of the bacterial primosome protein, DnaD. Although the RepA and DnaD NTD both contain winged helix-turn-helices, the DnaD NTD self-assembles into large scaffolds whereas the tetrameric RepA NTD binds DNA iterons using a newly described DNA binding mode. Strikingly, structural and atomic force microscopy data reveal that the NTD tetramer mediates DNA bridging, suggesting a molecular mechanism for origin handcuffing. Finally, data show that the RepA CTD interacts with the host DnaG primase, which binds the replicative helicase. Thus, these combined data reveal the molecular mechanism by which RepA mediates the specific replicon assembly of staphylococcal multiresistant plasmids.
- Subjects :
- Protein Structure, Tertiary
Bacterial Proteins chemistry
Bacterial Proteins genetics
Bacterial Proteins metabolism
DNA Helicases chemistry
DNA Helicases immunology
DNA Helicases metabolism
Drug Resistance, Multiple, Bacterial physiology
Plasmids chemistry
Plasmids genetics
Plasmids metabolism
Staphylococcus aureus chemistry
Staphylococcus aureus genetics
Staphylococcus aureus metabolism
Trans-Activators chemistry
Trans-Activators immunology
Trans-Activators metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1091-6490
- Volume :
- 111
- Issue :
- 25
- Database :
- MEDLINE
- Journal :
- Proceedings of the National Academy of Sciences of the United States of America
- Publication Type :
- Academic Journal
- Accession number :
- 24927575
- Full Text :
- https://doi.org/10.1073/pnas.1406065111