title: Measuring and Suppressing the Oxidative Damage to DNA During Cu(I)-Catalyzed Azide-Alkyne Cycloaddition.
abstract: We have used the quantitative polymerase chain reaction (qPCR) to measure the extent of oxidative DNA damage under varying reaction conditions used for copper(I)-catalyzed click chemistry. We systematically studied how the damage depends on a number of key reaction parameters, including the amounts of copper, ascorbate, and ligand used, and found that the damage is significant under nearly all conditions tested, including those commonly used for bioconjugation. Furthermore, we discovered that the addition of dimethyl sulfoxide, a known radical scavenger, into the aqueous mixture dramatically suppresses DNA damage during the reaction. We also measured the efficiency of cross-linking two short synthetic oligonucleotides via click chemistry, and found that the reaction could proceed reasonably efficiently even with DMSO present. This approach for screening both DNA damage and reactivity under a range of reaction conditions will be valuable for improving the biocompatibility of click chemistry, and should help to extend this powerful synthetic tool for both in vitro and in vivo applications.
authors.affiliation: Chemistry & Chemical Biology, School of Natural Sciences, University of California, Merced , 5200 North Lake Road, Merced, California 95343, United States.
authors.forename: Gary R
authors.initials: GR
authors.lastname: Abel
authors.affiliation: Chemistry & Chemical Biology, School of Natural Sciences, University of California, Merced , 5200 North Lake Road, Merced, California 95343, United States.
authors.forename: Zachary A
authors.initials: ZA
authors.lastname: Calabrese
authors.affiliation: Chemistry & Chemical Biology, School of Natural Sciences, University of California, Merced , 5200 North Lake Road, Merced, California 95343, United States.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Ayco
authors.affiliation: Chemistry & Chemical Biology, School of Natural Sciences, University of California, Merced , 5200 North Lake Road, Merced, California 95343, United States.|Department of Chemistry, UBC Faculty of Science, The University of British Columbia , 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1.
authors.forename: Jason E
authors.initials: JE
authors.lastname: Hein
authors.affiliation: Chemistry & Chemical Biology, School of Natural Sciences, University of California, Merced , 5200 North Lake Road, Merced, California 95343, United States.
authors.forename: Tao
authors.initials: T
authors.lastname: Ye
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D061565:Cycloaddition Reaction; D004249:DNA Damage; D018384:Oxidative Stress
chemical_list: D000480:Alkynes; D001386:Azides; D003300:Copper