暴露于异种生物如石油衍生的多环芳烃(PAHs)的鱼将通过有效的生物转化反应立即启动解毒系统。然而,在PAH暴露如石油污染后,识别的代谢途径与鱼中检测到的实际代谢产物之间存在差异。为了加深我们对PAH解毒的理解,我们进行了实验,将大西洋黑线dock(Melanogrammusaeglefinus)暴露于单个PAHs或复杂的油混合物。胆汁提取物,通过使用离子迁移率四极杆飞行时间质谱仪进行分析,揭示了与巯基尿酸途径相关的新型代谢物。公认为PAH硫醇的主要光谱特征为针对(i)谷胱甘肽-,(ii)半胱氨酰甘氨酸-,(iii)半胱氨酸─和(iv)巯基尿酸S-缀合物。基于受控的单次曝光实验,我们构建了一个来自8种PAHs(蒽,菲,1-甲基菲,1,4-二甲基菲,chrysene,奔驰[a]蒽,苯并[a]芘,和迪本斯[a,h]蒽)。通过将文库纳入原油暴露鱼的样品分析中,发现了与谷胱甘肽和半胱氨酰甘氨酸缀合的PAHs。这项定性研究提供了对鱼类中鲜为人知的巯基尿酸解毒途径的独家了解。此外,这提供了证据,证明这种代谢途径也对复杂污染源中的PAHs成功,一个以前没有报道过的显著发现。
Fish exposed to xenobiotics like petroleum-derived polycyclic aromatic hydrocarbons (PAHs) will immediately initiate detoxification systems through effective biotransformation reactions. Yet, there is a discrepancy between recognized metabolic pathways and the actual metabolites detected in fish following PAH exposure like oil pollution. To deepen our understanding of PAH detoxification, we conducted experiments exposing Atlantic haddock (Melanogrammus aeglefinus) to individual PAHs or complex oil mixtures. Bile extracts, analyzed by using an ion mobility quadrupole time-of-flight mass spectrometer, revealed novel metabolites associated with the mercapturic acid pathway. A dominant spectral feature recognized as PAH thiols set the basis for a screening strategy targeting (i) glutathione-, (ii) cysteinylglycine-, (iii) cysteine-, and (iv) mercapturic acid S-conjugates. Based on controlled single-exposure experiments, we constructed an interactive library of 33 metabolites originating from 8 PAHs (anthracene, phenanthrene, 1-methylphenanthrene, 1,4-dimethylphenanthrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene). By incorporation of the library in the analysis of samples from crude oil exposed fish, PAHs conjugated with glutathione and cysteinylglycine were uncovered. This qualitative study offers an exclusive glimpse into the rarely acknowledged mercapturic acid detoxification pathway in fish. Furthermore, this furnishes evidence that this metabolic pathway also succeeds for PAHs in complex pollution sources, a notable discovery not previously reported.