Plasmid DNA damage induced by singlet molecular oxygen released from the naphthalene endoperoxide DHPNO2 and photoactivated methylene blue
AUTOR(ES)
Berra, Carolina Maria, Menck, Carlos Frederico Martins, Martinez, Glaucia Regina, Oliveira, Carla Santos de, Baptista, Maurício da Silva, Di Mascio, Paolo
FONTE
Química Nova
DATA DE PUBLICAÇÃO
2010
RESUMO
To investigate oxidative lesions and strand breaks induction by singlet molecular oxygen (¹O2), supercoiled-DNA plasmid was treated with thermo-dissociated DHPNO2 and photoactivated-methylene blue. DNA lesions were detected by Fpg that cleaves DNA at certain oxidized bases, and T4-endoV, which cleaves DNA at cyclobutane pyrimidine dimers and apurinic/apyrimidinic (AP) sites. These cleavages form open relaxed-DNA structures, which are discriminated from supercoiled-DNA. DHPNO2 or photoactivated-MB treatments result in similar plasmid damage profile: low number of single-strand breaks or AP-sites and high frequency of Fpg-sensitive sites; confirming that base oxidation is the main product for both reactions and that ¹O2 might be the most likely intermediate that reacts with DNA.
Documentos Relacionados
- Characterization of Photoactivated Singlet Oxygen Damage in Single-Molecule Optical Trap Experiments
- Spermine and spermidine protection of plasmid DNA against single-strand breaks induced by singlet oxygen.
- Enzymatic recognition of DNA modifications induced by singlet oxygen and photosensitizers.
- Homogenous repair of singlet oxygen-induced DNA damage in differentially transcribed regions and strands of human mitochondrial DNA.
- A proposed function for spermine and spermidine: protection of replicating DNA against damage by singlet oxygen.