Nanopore detection of 8-oxo-7,8-dihydro-2'-deoxyguanosine in immobilized single-stranded DNA via adduct formation to the DNA damage site.
The ability to detect DNA damage within the context of the surrounding sequence is an important goal in medical diagnosis and therapies, but there are no satisfactory methods available to detect a damaged base while providing sequence information. One of the most common base lesions is 8-oxo-7,8-dihydroguanine, which occurs during oxidation of guanine. In the work presented here, we demonstrate the detection of a single oxidative damage site using ion channel nanopore methods employing α-hemolysin. Hydantoin lesions produced from further oxidation of 8-oxo-7,8-dihydroguanine, as well as spirocyclic adducts produced from covalently attaching a primary amine to the spiroiminodihydantoin lesion, were detected by tethering the damaged DNA to streptavidin via a biotin linkage and capturing the DNA inside an α-hemolysin ion channel. Spirocyclic adducts, in both homo- and heteropolymer background single-stranded DNA sequences, produced current blockage levels differing by almost 10% from those of native base current blockage levels. These preliminary studies show the applicability of ion channel recordings not only for DNA sequencing, which has recently received much attention, but also for detecting DNA damage, which will be an important component to any sequencing efforts.
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA.
Anna E P
AE
Schibel
Na
N
An
Qian
Q
Jin
Aaron M
AM
Fleming
Cynthia J
CJ
Burrows
Henry S
HS
White
D000080242:8-Hydroxy-2'-Deoxyguanosine; D018736:DNA Adducts / Q000737:chemistry*; D004249:DNA Damage; D004277:DNA, Single-Stranded / Q000737:chemistry*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000032:analysis; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000737:chemistry*; D006827:Hydantoins / Q000737:chemistry; D007473:Ion Channels / Q000737:chemistry*; D008722:Methods; D058608:Nanopores; D018384:Oxidative Stress
D018736:DNA Adducts; D004277:DNA, Single-Stranded; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D006827:Hydantoins; D007473:Ion Channels; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine