Perera Rukshan T, Fleming Aaron M, Johnson Robert P, Burrows Cynthia J, White Henry S
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA.
Nanotechnology. 2015 Feb 20;26(7):074002. doi: 10.1088/0957-4484/26/7/074002. Epub 2015 Jan 28.
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 (αHL) 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 αHL 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 αHL, presenting opportunities for the monitoring, quantification, and sequencing of mutagenic compounds from cellular DNA samples.
致癌前体苯并[a]芘（BP）是一种多环芳烃，通过碳氢化合物的不完全燃烧释放到环境中。BP在人体内的代谢产生一种强效烷基化剂（苯并[a]芘二醇环氧化物，BPDE），它与DNA中的鸟嘌呤（G）反应形成一种与癌症起始有关的加合物。我们报告称，α-溶血素（αHL）纳米孔平台可用于检测合成寡脱氧核苷酸中BPDE与G的加合物。一条含有位于中央的BPDE与G加合物的41聚体聚2'-脱氧胞苷链在1 M KCl中通过αHL易位时，会产生独特的多级电流特征，从而能够检测到该加合物。当BPDE加合的DNA链从5'或3'方向易位时，都能观察到这种易于区分的电流调制。这项研究表明，αHL可检测BPDE加合物和其他大型芳香族生物标志物，为监测、定量和测序细胞DNA样本中的诱变化合物提供了机会。
