Forschungszentrum Jülich, IBG-1: Biotechnology, 52425 Jülich, Germany.
Curr Opin Biotechnol. 2013 Dec;24(6):979-86. doi: 10.1016/j.copbio.2013.03.024. Epub 2013 Apr 24.
Metabolic flux analysis (MFA) using isotopic tracers aims at the experimental determination of in vivo reaction rates (fluxes). In recent years, the well-established 13C-MFA method based on metabolic and isotopic steady state was extended to INST-MFA (isotopically non-stationary MFA), which is performed in a transient labeling state. INST-MFA offers short-time experiments with a maximal information gain, and can moreover be applied to a wider range of growth conditions or organisms. Some of these conditions are not accessible by conventional methods. This comes at the price of significant methodological complexity involving high-frequency sampling and quenching, precise analysis of many samples and an extraordinary computational effort. This review gives a brief overview of basic principles, experimental workflows, and recent progress in this field. Special emphasis is laid on the trade-off between total effort and information gain, particularly on the suitability of INST-MFA for certain types of biological questions. In order to integrate INST-MFA as a viable method into the toolbox of MFA, some major challenges must be addressed in the coming years. These are discussed in the outlook.
代谢通量分析（MFA）使用同位素示踪剂旨在实验确定体内反应速率（通量）。近年来，基于代谢和同位素稳态的成熟的 13C-MFA 方法已经扩展到 INST-MFA（同位素非稳态 MFA），该方法在瞬态标记状态下进行。INST-MFA 提供了具有最大信息增益的短时间实验，并且可以应用于更广泛的生长条件或生物体。其中一些条件是常规方法无法达到的。这是有代价的，涉及高频采样和淬火、对许多样本进行精确分析以及非凡的计算工作量的显著方法复杂性。这篇综述简要概述了该领域的基本原理、实验工作流程和最新进展。特别强调了总工作量和信息增益之间的权衡，特别是 INST-MFA 对某些类型的生物学问题的适用性。为了将 INST-MFA 作为一种可行的方法整合到 MFA 的工具包中，未来几年必须解决一些主要挑战。在展望中讨论了这些问题。
