Delta-elimination in the repair of AP (apurinic/apyrimidinic) sites in DNA.
[5'-32P]pdT8d(-)dT7, containing an AP (apurinic/apyrimidinic) site in the ninth position, and [d(-)-1',2'-3H, 5'-32P]DNA, containing AP sites labelled with 3H in the 1' and 2' positions of the base-free deoxyribose [d(-)] and with 32P 5' to this deoxyribose, were used to investigate the yields of the beta-elimination and delta-elimination reactions catalysed by spermine, and also the yield of hydrolysis, by the 3'-phosphatase activity of T4 polynucleotide kinase, of the 3'-phosphate resulting from the beta delta-elimination. Phage-phi X174 RF (replicative form)-I DNA containing AP (apurinic) sites has been repaired in five steps: beta-elimination, delta-elimination, hydrolysis of 3'-phosphate, DNA polymerization and ligation. Spermine, in one experiment, and Escherichia coli formamidopyrimidine: DNA glycosylase, in another experiment, were used to catalyse the first and second steps (beta-elimination and delta-elimination). These repair pathways, involving a delta-elimination step, may be operational not only in E. coli repairing its DNA containing a formamido-pyrimidine lesion, but also in mammalian cells repairing their nuclear DNA containing AP sites.
Bailly
V
V
Department of Biochemistry, Faculty of Sciences, University of Liège, Belgium.
Derydt
M
M
Verly
W G
WG
D001080:Apurinic Acid; D010584:Bacteriophage phi X 174 / Q000235:genetics; D011088:DNA Ligases / Q000502:physiology; D004256:DNA Polymerase I / Q000502:physiology; D004260:DNA Repair; D004279:DNA, Viral / Q000187:drug effects; D011116:Polynucleotide 5'-Hydroxyl-Kinase / Q000378:metabolism; D011119:Polynucleotides; D013096:Spermine / Q000494:pharmacology
D004279:DNA, Viral; D011119:Polynucleotides; C001790:apyrimidinic acid; D001080:Apurinic Acid; D013096:Spermine; D011116:Polynucleotide 5'-Hydroxyl-Kinase; D004256:DNA Polymerase I; D011088:DNA Ligases