Mass Spectrometric Identification of 13C‐Labeled Metabolites During Anaerobic Propanoic Acid Oxidation
Mass Spectrometric Identification of 13C‐Labeled Metabolites During Anaerobic Propanoic Acid Oxidation
复制标题
厌氧丙酸氧化过程中 13C 标记代谢物的质谱鉴定
DOI：
10.1002/cbdv.201100030
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发表时间：
2012
影响因子：
2.9
通讯作者：
C. Gallert
中科院分区：
文献类型：
--
作者：
Monika Felchner;J. Winter;C. Gallert
生物废弃物消化是获得沼气作为可再生燃料来源的可能性。然而，厌氧食物链可能会被破坏，例如，底物过载或抑制剂，导致挥发性脂肪酸（VFA），主要是丙酸（PA）的积累。VFA的积累可能导致pH值迅速下降，沼气产量减少，甚至完全抑制。为了保持高的生物气生产率或防止产甲烷的崩溃，必须阐明降解微生物的代谢特性，例如，通过研究VFAs的既定降解途径。结合Dani 3950顶空系统（HS）、Varian 431气相色谱仪（GC）和Varian 210质谱仪（MS），对PA氧化的代谢物进行定量和特异性鉴定。使用[1 - 13 C]-标记的PA作为微生物的碳源，可以区分甲基丙二酰辅酶A或C（6）-歧化途径，两者都导致AcOH的产生。在AcO的COO或Me基团中出现的13 C-部分可以通过MS容易地检测到。甲基丙二酰辅酶A途径被成功鉴定为实验室规模厌氧消化器中生物体降解PA的唯一途径。类似的方法可应用于涉及VFA的任何降解途径。
Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse of methanogenesis, metabolic properties of the degrading microorganisms must be elucidated, e.g., by investigation of the established pathways for degradation of VFAs. A Dani 3950 headspace system (HS), a Varian 431 gas chromatograph (GC), and a Varian 210 mass spectrometer (MS) have been combined to quantify and specifically identify metabolites of PA oxidation. The use of [1‐13C]‐labeled PA as a carbon source for microorganisms allows differentiation between the methyl‐malonyl‐CoA or the C(6)‐dismutation pathway, both resulting in AcOH production. Appearance of the 13C‐moiety either in the COO or Me group of AcO can easily be detected by MS. The methyl‐malonyl‐CoA pathway was successfully identified as the only pathway of PA degradation by organisms in a lab‐scale anaerobic digester. A similar approach can be applied to any degradation pathway involving VFAs.
影响因子：
7.7
作者：
McInerney, Michael J.;Sieber, Jessica R.;Gunsalus, Robert P.
通讯作者：
Gunsalus, Robert P.