title: Oligonucleotide duplexes containing CC(A/T)GG stimulate cleavage of refractory DNA by restriction endonuclease EcoRII.
abstract: Some DNA species are resistant towards the restriction endonuclease EcoRII despite the presence of unmodified recognition sites. We show that 14 base-pair oligonucleotide duplexes containing the EcoRII recognition site 5'-CC(A/T)GG are cleaved by this enzyme and are able to stimulate EcoRII cleavage of such resistant DNA molecules (e.g. DNA of bacterial virus T3). A direct correlation between the concentration of oligonucleotide duplex molecules and the degree of EcoRII digestion of the primarily resistant DNA is observed. This indicates a stoichiometric rather than a catalytic mode of enzyme activation. An excess of DNA devoid of EcoRII sites ('non-site' DNA, e.g. MvaI-digested T7 DNA) does not interfere with the activity of EcoRII.
authors: Department of Chemistry, Humboldt University, Berlin, GDR.
authors: C D
authors: CD
authors: Pein
authors: M
authors: M
authors: Reuter
authors: D
authors: D
authors: Cech
authors: D H
authors: DH
authors: Krüger
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D002384:Catalysis; D004279:DNA, Viral / Q000378:metabolism*; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D009841:Oligonucleotides / Q000378:metabolism / Q000494:pharmacology*; D013379:Substrate Specificity; D013604:T-Phages
chemical_list: D004279:DNA, Viral; D009841:Oligonucleotides; C046545:CCWGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific