Plasmid DNA damage induced by singlet molecular oxygen released from the naphthalene endoperoxide DHPNO2 and photoactivated methylene blue

• Autor(a) principal: Berra, Carolina Maria
• Data de Publicação: 2010
• Outros Autores: Menck, Carlos Frederico Martins, Martinez, Glaucia Regina, Oliveira, Carla Santos de, Baptista, Maurício da Silva, Di Mascio, Paolo
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFMS
• Texto Completo: https://repositorio.ufms.br/handle/123456789/147
• topic: Estresse Oxidativo; Dano ao DNA; Oxidative Stress; Oxidative Stress; DNA Damage; Singlet Oxygen

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.