title: DNA cleavage study using copper (II)-GlyAibHis: a tripeptide complex based on ATCUN peptide motifs.
abstract: Development of new chemical nucleases is a matter of great interest because of their extensive use in biotechnology and as therapeutic agents. The ATCUN (amino terminal Cu(II) and Ni(II) binding) is a peptide motif that occurs naturally in the serum albumins. The similar peptide motif (GlyAibHis) having unnatural amino acid Aib (alpha-aminoisobutyric acid) was synthesized and its Cu(II) complex was characterized by ESI-MS and spectrophotometry studies. The reactivity of this complex toward DNA cleavage has been investigated. Cu(II)-GlyAibHis shows the DNA cleavage only in presence of mild oxidizing agents like ascorbate by an oxidative mechanism rather than hydrolytic and follows the pseudo first order kinetics (K obs = 0.085 min(-1)). The non-hydrolytic mechanism was further supported by the hydrolysis of pNPP which followed the pseudo first order kinetics (K obs = 1.98 x 10(-2) min(-1)) having no pH effect.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee - 247 667, India.
authors.forename: Raj Kumar
authors.initials: RK
authors.lastname: Singh
authors.forename: Nilesh Kumar
authors.initials: NK
authors.lastname: Sharma
authors.forename: Ramasre
authors.initials: R
authors.lastname: Prasad
authors.forename: Udai Pratap
authors.initials: UP
authors.lastname: Singh
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D003300:Copper / Q000378:metabolism*; D053837:DNA Cleavage; D006868:Hydrolysis; D008667:Metalloproteins / Q000378:metabolism*; D009532:Nickel / Q000378:metabolism*; D009842:Oligopeptides / Q000378:metabolism*; D010084:Oxidation-Reduction; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D008667:Metalloproteins; D009842:Oligopeptides; D003300:Copper; D009532:Nickel