English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/39552
logo share SHARE   Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Assembly of phage phi 29 genome with viral protein p6 into a compact complex

AuthorsGutiérrez Armenta, Crisanto ; Freire, Raimundo ; Salas, Margarita ; Hermoso, José Miguel
KeywordsElectron microscopy/
Histone-like proteins
Nucleoprotein complex
Phage φ29
Issue Date1-Jan-1994
PublisherNature Publishing Group
CitationEmbo Journal 13(1):269-276 (1994)
AbstractThe formation of a multimeric nucleoprotein complex by the phage phi 29 dsDNA binding protein p6 at the phi 29 DNA replication origins, leads to activation of viral DNA replication. In the present study, we have analysed protein p6-DNA complexes formed in vitro along the 19.3 kb phi 29 genome by electron microscopy and micrococcal nuclease digestion, and estimated binding parameters. Under conditions that greatly favour protein-DNA interaction, the saturated phi 29 DNA-protein p6 complex appears as a rigid, rod-like, homogeneous structure. Complex formation was analysed also by a psoralen crosslinking procedure that did not disrupt complexes. The whole phi 29 genome appears, under saturating conditions, as an irregularly spaced array of complexes approximately 200-300 bp long; however, the size of these complexes varies from approximately 2 kb to 130 bp. The minimal size of the complexes, confirmed by micrococcal nuclease digestion, probably reflects a structural requirement for stability. The values obtained for the affinity constant (K(eff) approximately 10(5) M-1) and the cooperativity parameter (omega approximately 100) indicate that the complex is highly dynamic. These results, together with the high abundance of protein p6 in infected cells, lead us to propose that protein p6-DNA complexes could have, at least at some stages, during infection, a structural role in the organization of the phi 29 genome into a nucleoid-type, compact nucleoprotein complex.
Publisher version (URL)http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/8306969/?tool=pubmed
Appears in Collections:(CBM) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.