title: Biomolecular response of oxanine in DNA strands to T4 polynucleotide kinase, T4 DNA ligase, and restriction enzymes.
abstract: Oxanine (Oxa), generated from guanine (Gua) by NO- or HNO(2)-induced nitrosative oxidation, has been thought to cause mutagenic problems in cellular systems. In this study, the response of Oxa to different enzymatic functions was explored to understand how similarly it can participate in biomolecular reactions compared to the natural base, Gua. The phosphorylation efficiency of the T4 polynucleotide kinase was highest when Oxa was located on the 5'-end of single stranded DNAs compared to when other nucleobases were in this position. The order of phosphorylation efficiency was as follows; Oxa>Gua>adenine (Ade) approximately thymine (Thy)>cytosine (Cyt). Base-pairing of Oxa and Cyt (Oxa:Cyt) between the ligation fragment and template was found to influence the ligation performance of the T4 DNA ligase to a lesser degree compared to Gua:Cyt. In addition, EcoRI and BglII showed higher cleavage activities on DNA substrates containing Oxa:Cyt than those containing Gua:Cyt, while BamHI, HindIII and EcoRV showed lower cleavage activity; however, this decrease in activity was relatively small.
authors.affiliation: Department of Biotechnology and Bioinformatics, Korea University, Jochiwon, Chungnam 339-800, Republic of Korea. spack@korea.ac.kr
authors.forename: Seung Pil
authors.initials: SP
authors.lastname: Pack
authors.forename: Akihiro
authors.initials: A
authors.lastname: Doi
authors.forename: Yoo Seong
authors.initials: YS
authors.lastname: Choi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kodaki
authors.forename: Keisuke
authors.initials: K
authors.lastname: Makino
mesh_terms: D020029:Base Pairing; D003596:Cytosine / Q000737:chemistry; D053837:DNA Cleavage; D011088:DNA Ligases / Q000737:chemistry*; D004262:DNA Restriction Enzymes / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000235:genetics; D010766:Phosphorylation; D011116:Polynucleotide 5'-Hydroxyl-Kinase / Q000737:chemistry*; D011684:Purine Nucleosides / Q000737:chemistry* / Q000235:genetics
chemical_list: D004277:DNA, Single-Stranded; D011684:Purine Nucleosides; C468766:oxanine; D003596:Cytosine; D011116:Polynucleotide 5'-Hydroxyl-Kinase; D004262:DNA Restriction Enzymes; D011088:DNA Ligases