The formation of one-G deletions as a consequence of single-oxygen-induced DNA damage.
Single-stranded M13mp10 DNA containing a 144-bp mutational target sequence in the lacZ alpha gene was treated with singlet oxygen (1O2) generated by thermodissociation of the endoperoxide of 3,3'-(1,4-naphthalene-1,4-diyl)dipropionate (NDPO2). After transfection to non-SOS-induced E. coli cells, 32 mutants preselected for a mutation in the 144-bp target were collected and analyzed by DNA sequencing. One-G deletions represented the predominant type of mutation accounting for 50% of the mutations analyzed. The remaining part appeared to consist of base substitutions, i.e. G-->T transversions (34%), C-->T transitions (12.5%) and one T-->C transition (3%). Sixty percent of the mutations were found in two major mutational hotspots. We conclude that the predominant one-G deletions are due to a guanine reaction product which might be specific for 1O2.
van den Akker
E
E
Institute of Human Genetics, Vrije Universiteit, Amsterdam, The Netherlands.
Lutgerink
J T
JT
Lafleur
M V
MV
Joenje
H
H
Retèl
J
J
D017104:Bacteriophage M13 / Q000235:genetics; D001483:Base Sequence; D004249:DNA Damage; D004252:DNA Mutational Analysis; D004279:DNA, Viral / Q000187:drug effects; D004926:Escherichia coli / Q000235:genetics; D006147:Guanine; D008969:Molecular Sequence Data; D009153:Mutagens / Q000737:chemistry / Q000633:toxicity*; D009284:Naphthols; D010100:Oxygen / Q000737:chemistry / Q000633:toxicity*; D017354:Point Mutation; D017384:Sequence Deletion; D026082:Singlet Oxygen
D004279:DNA, Viral; D009153:Mutagens; D009284:Naphthols; D026082:Singlet Oxygen; D006147:Guanine; C058008:3,3'-(1,4-naphthylidene)diproprionate; D010100:Oxygen