Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-11-19
pubmed:abstractText
The transmissive plasmid IncI1 R64 contains the ardA gene encoding the ArdA antirestriction protein. The R64 ardA gene locating in the leading region of plasmid R64 has been cloned and their sequence has been determined. Antirestriction proteins belonging to the Ard family are specific inhibitors of type I restriction-modification enzymes. The IncI1 ColIb-P9 and R64 are closely related plasmids, and the latter specifies an ArdA homologue that is predicted to be 97.6% (162 residues from 166) identical at the amino acid sequence level with the ColIb = P9 equivalent. However, the R64 ArdA selectively inhibits the restriction activity of EcoKi enzyme leaving significant levels of modification activity under conditions in which restriction was almost completely prevented. The ColIb-P9 ArdA inhibits restriction endonuclease and methyltransferase activities simultaneously. It is hypothesized that the ArdA protein forms two complexes with the type I restriction-modification enzyme (R2M2S): (1) with a specific region in the S subunit involved in contact with the sK site in DNA; and (2) with nonspecific region in the R subunit involved in DNA translocation and degradation by restriction endonuclease. The association of the ColIb-P9 ArdA with the specific region inhibits restriction endonuclease and methyltransferase activities simultaneously, whereas the association of the R64 ArdA with a nonspecific region inhibits only restriction endonuclease activity of the R2M2S enzyme.
pubmed:language
rus
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0026-8984
pubmed:author
pubmed:issnType
Print
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
901-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
[Antirestriction activity of the IncI1 transmissive plasmid R64 ArdA protein].
pubmed:publicationType
Journal Article, English Abstract