title: Studies on cleavage of DNA by N-phosphoryl branched peptides.
abstract: It was found that Nalpha,Nepsilon-di[N-(O,O-diisopropyl)phosphoryl-L-leucy]-L-lysyl-methyl ester (1) and Nalpha,Nepsilon-di[N-(O,O-diisopropyl)phosphoryl-L-phenylalanyl]-L-lysyl-methyl ester (2) could cleave supercoiled DNA such as PUC19 efficiently in 40 mM Britton-Robinson buffer. The cleavage activities for both were investigated by agarose gel electrophoresis. The T4 ligase experiments implied that the cleavage of DNA occurs via a hydrolytic path. The results showed that the cleavage reaction of DNA is dependent on the value of pH and ionic strength in the solution. DNA cleavage is more efficient by N-phosphoryl branched peptide 2 than by N-phosphoryl branched peptide 1. The experiments also show that hydrolysis of DNA by N-phosphoryl branched peptide 1 was accelerated in the presence of Mg2+ or Zn2+ ions. The interactions of DNA with N-phosphoryl branched peptides were also characterized by melting temperature measurements and circular dichroism (CD) techniques. On the basis of experimental data, the possible mechanism of interactions between DNA with N-phosphoryl branched peptides was discussed.
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, PR China. fengyp@mail.tsinghua.edu.cn
authors.forename: Yuping
authors.initials: Y
authors.lastname: Feng
authors.forename: Shengli
authors.initials: S
authors.lastname: Cao
authors.forename: Anshan
authors.initials: A
authors.lastname: Xiao
authors.forename: Wenjun
authors.initials: W
authors.lastname: Xie
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Li
authors.forename: Yufen
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D004249:DNA Damage; D011088:DNA Ligases / Q000378:metabolism; D004587:Electrophoresis, Agar Gel; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008274:Magnesium / Q000737:chemistry; D008956:Models, Chemical; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*; D012492:Salts / Q000494:pharmacology; D015032:Zinc / Q000737:chemistry
chemical_list: D007477:Ions; D010455:Peptides; D012492:Salts; D004247:DNA; D011088:DNA Ligases; D008274:Magnesium; D015032:Zinc