Detection of benzo[a]pyrene-guanine adducts in single-stranded DNA using the α -hemolysin nanopore

The carcinogenic precursor benzo[a]pyrene (BP), a polycyclic aromatic hydrocarbon, is released into the environment through the incomplete combustion of hydrocarbons. Metabolism of BP in the human body yields a potent alkylating agent (benzo[a]pyrene diol epoxide, BPDE) that reacts with guanine (G) in DNA to form an adduct implicated in cancer initiation. We report that the α -hemolysin ( α HL) nanopore platform can be used to detect a BPDE adduct to G in synthetic oligodeoxynucleotides. Translocation of a 41-mer poly-2′-deoxycytidine strand with a centrally located BPDE adduct to G through α HL in 1 M KCl produces a unique multi-level current signature allowing the adduct to be detected. This readily distinguishable current modulation was observed when the BPDE-adducted DNA strand translocated from either the 5′ or 3′ directions. This study suggests that BPDE adducts and other large aromatic biomarkers can be detected with α HL, presenting opportunities fo...

Rukshan T Perera, Aaron M Fleming, Robert P Johnson, Cynthia J Burrows and Henry S White

Click for full article