Growth of Sphingobium barthaii KK22 on 1-ethylnaphthalene reveals diverse oxidative transformations and a complex metabolite profile
Growth of Sphingobium barthaii KK22 on 1-ethylnaphthalene reveals diverse oxidative transformations and a complex metabolite profile
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巴氏鞘氨醇 KK22 在 1-乙基萘上的生长揭示了多种氧化转化和复杂的代谢物谱
DOI：
10.1016/j.ibiod.2022.105500
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Kanaly Robert A.
中科院分区：
文献类型：
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作者：
Sakai Miharu;Tomiyama Yuna;Mori Jiro F.;Kanaly Robert A.
烷基化多环芳烃（APAHs）是原油和石油污染沉积物的主要组成部分，包括相对不溶于水的多烷基链烷基化多环芳烃（CA-PAH）。关于微生物对CA-PAH的转化知之甚少，因此尚未建立生物降解途径。采用气相色谱和综合液相色谱-电喷雾串联质谱法研究了土壤细菌Sphingobium barthaiiKK 22对1-乙基萘（1-EN）的生物转化。1-EN被菌株KK 22用作唯一的碳和能量来源，并且200 mg/L的1-EN作为非水相液体在大约5天内从培养基中耗尽。1-EN通过芳环、烷基部分以及通过芳环和烷基部分氧化，导致不同的代谢物谱，包括不同的羧酸代谢物和缀合产物。组织转化产物以构建细菌将1-EN转化为TCA循环的第一个广泛描述。关键的生物转化产物，如1-萘甲酸和3-乙基儿茶酚进行了鉴定，并使用1-甲基萘和1-萘甲酸的独立转化试验的结果证实了1-EN试验的结果。这项工作表明，鞘单胞菌可能是减少污染环境中CA-PAH的多方面贡献者。
Alkylated polycyclic aromatic hydrocarbons (APAHs) are major components of crude oils and petroleum-contaminated sediments and include the relatively water insoluble polyalkyl chain-alkylated PAHs (CA-PAHs). Little is known regarding CA-PAH transformation by microorganisms and therefore biodegradation pathways have not been established. Biotransformation of the CA-PAH 1-ethylnaphthalene (1-EN) by soil bacteriumSphingobium barthaiiKK22 was investigated by gas chromatography and comprehensive liquid chromatography electrospray ionization tandem mass spectrometry analyses. 1-EN was utilized as a sole source of carbon and energy by strain KK22 and 200 mg/L of 1-EN as a nonaqueous phase liquid was depleted from culture media in approximately 5 days. 1-EN was oxidized through the aromatic rings, the alkyl moiety and through both the aromatic rings and the alkyl moiety resulting in a diverse metabolite profile that included different carboxylic acid metabolites and conjugation products. Transformation products were organized to construct the first extensive description of 1-EN transformation to the TCA cycle by a bacterium. Key biotransformation products such as 1-naphthoic acid and 3-ethylcatechol were identified and results of independent transformation assays using 1-methylnaphthalene and 1-naphthoic acid confirmed results from 1-EN assays. This work shows that sphingomonads may be versatile contributors to the reduction of CA-PAHs in contaminated environments.