Biomaterial Database

DNA synthesis blocking lesions induced by singlet oxygen are targeted to deoxyguanosines. 1992

D T Ribeiro, and F Bourre, and A Sarasin, and P Di Mascio, and C F Menck

Departamento de Biologia, Universidade de São Paulo, Brazil.

In vitro DNA synthesis on single stranded templates damaged by singlet oxygen was investigated in the supF tRNA gene sequence, using several DNA polymerases. Singlet oxygen was generated by the thermal decomposition of the water soluble with the endoperoxide of disodium 3,3'-(1,4-naphthylidene) dipropionate (NDPO2). The data demonstrated that damage at deoxyguanosine residues interrupts DNA polymerization. Modified T7 phage and Thermus aquaticus DNA polymerases were found to synthesize DNA fragments which terminated opposite deoxyguanosine, while T4 phage DNA polymerase and avian myeloblast virus reverse transcriptase were blocked one nucleotide 3' to deoxyguanosine positions on the template. DNA polymerase I (Klenow fragment) from Escherichia coli was inhibited at both positions, before and at the putative damaged sites. The blocking lesions, induced by 5 mM NDPO2, were estimated to be approximately 1.5 per 260 nucleotides, corresponding to 2% of deoxyguanosines. The distribution of lesions in the supF gene did not reveal any specific sequence context which showed distinct susceptibility to the attack of singlet oxygen.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009284	Naphthols	Naphthalene derivatives carrying one or more hydroxyl (-OH) groups at any ring position. They are often used in dyes and pigments, as antioxidants for rubber, fats, and oils, as insecticides, in pharmaceuticals, and in numerous other applications.	Hydroxynaphthalene,Hydroxynaphthalenes,Naphthol
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D010777	Photochemistry	A branch of physical chemistry which studies chemical reactions, isomerization and physical behavior that may occur under the influence of visible and/or ultraviolet light.	Photochemistries
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D003849	Deoxyguanosine	A nucleoside consisting of the base guanine and the sugar deoxyribose.
D004259	DNA-Directed DNA Polymerase	DNA-dependent DNA polymerases found in bacteria, animal and plant cells. During the replication process, these enzymes catalyze the addition of deoxyribonucleotide residues to the end of a DNA strand in the presence of DNA as template-primer. They also possess exonuclease activity and therefore function in DNA repair.	DNA Polymerase,DNA Polymerases,DNA-Dependent DNA Polymerases,DNA Polymerase N3,DNA Dependent DNA Polymerases,DNA Directed DNA Polymerase,DNA Polymerase, DNA-Directed,DNA Polymerases, DNA-Dependent,Polymerase N3, DNA,Polymerase, DNA,Polymerase, DNA-Directed DNA,Polymerases, DNA,Polymerases, DNA-Dependent DNA
D004260	DNA Repair	The removal of DNA LESIONS and/or restoration of intact DNA strands without BASE PAIR MISMATCHES, intrastrand or interstrand crosslinks, or discontinuities in the DNA sugar-phosphate backbones.	DNA Damage Response
D004277	DNA, Single-Stranded	A single chain of deoxyribonucleotides that occurs in some bacteria and viruses. It usually exists as a covalently closed circle.	Single-Stranded DNA,DNA, Single Stranded,Single Stranded DNA
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli