Noncovalent Binding of Polycyclic Aromatic Hydrocarbons with Genetic Bases Reducing the in Vitro Lateral Transfer of Antibiotic Resistant Genes.
Noncovalent Binding of Polycyclic Aromatic Hydrocarbons with Genetic Bases Reducing the in Vitro Lateral Transfer of Antibiotic Resistant Genes.
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DOI：
10.1021/acs.est.5b02293
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发表时间：
2015-08
影响因子：
11.4
通讯作者：
Fuxing Kang;Xiaojie Hu;Juan Liu;Yanzheng Gao
中科院分区：
文献类型：
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作者：
Fuxing Kang;Xiaojie Hu;Juan Liu;Yanzheng Gao
在目前多环芳烃（PAHs）与遗传单元的非共价相互作用的研究中，这种相互作用对基因转移的影响尚未被探索。在这项研究中，我们研究了一些广泛存在的多环芳烃（菲，芘，苯并[g，h，i]二萘嵌苯，和其他同系物）与抗生素耐药质粒（pUC 19）。小分子多环芳烃（例如，菲）与质粒有效结合，形成松散的线团状质粒-PAH复合物（16.5-49.5 nm），导致氨苄青霉素抗性基因（Ampr）转化减少。体外转录分析表明，质粒中Ampr的转化减少是由于PAH抑制了Ampr向RNA的转录。荧光微量滴定结合傅里叶变换红外光谱（FTIR）和理论相互作用模型表明，质粒中的腺嘌呤通过π-π吸引作用对Phen和Pyre小分子具有较强的螯合能力。吉布斯自由能（ΔG）的变化表明，CT-PAH模型可靠地描述了质粒-PAH通过非共价物理吸附机制的相互作用。考虑到环境中多环芳烃和抗生素抗性基因（ARGs）的广泛存在，我们的研究结果表明，小尺寸的多环芳烃可以很好地影响ARGs的行为，通过上述非共价相互作用。
In current studies of noncovalent interactions of polycyclic aromatic hydrocarbons (PAHs) with genetic units, the impact of such interactions on gene transfer has not been explored. In this study, we examined the association of some widely occurring PAHs (phenanthrene, pyrene, benzo[g,h,i]perylene, and other congeners) with antibiotic resistant plasmids (pUC19). Small molecular PAHs (e.g., phenanthrene) bind effectively with plasmids to form a loosely clew-like plasmid-PAH complex (16.5-49.5 nm), resulting in reduced transformation of ampicillin resistance gene (Ampr). The in vitro transcription analysis demonstrated that reduced transformation of Ampr in plasmids results from the PAH-inhibited Ampr transcription to RNA. Fluorescence microtitration coupled with Fourier transform infrared spectroscopy (FTIR) and theoretical interaction models showed that adenine in plasmid has a stronger capacity to sequester small Phen and Pyre molecules via a π-π attraction. Changes in Gibbs free energy (ΔG) suggest that the CT-PAH model reliably depicts the plasmid-PAH interaction through a noncovalently physical sorption mechanism. Considering the wide occurrence of PAHs and antibiotic resistant genes (ARGs) in the environment, our findings suggest that small-sized PAHs can well affect the behavior of ARGs via above-described noncovalent interactions.