Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States.
Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
Metab Eng. 2017 May;41:173-181. doi: 10.1016/j.ymben.2017.04.005. Epub 2017 Apr 19.
Mono-ethylene glycol (MEG) is an important petrochemical with widespread use in numerous consumer products. The current industrial MEG-production process relies on non-renewable fossil fuel-based feedstocks, such as petroleum, natural gas, and naphtha; hence, it is useful to explore alternative routes of MEG-synthesis from gases as they might provide a greener and more sustainable alternative to the current production methods. Technologies of synthetic biology and metabolic engineering of microorganisms can be deployed for the expression of new biochemical pathways for MEG-synthesis from gases, provided that such promising alternative routes are first identified. We used the BNICE.ch algorithm to develop novel and previously unknown biological pathways to MEG from synthesis gas by leveraging the Wood-Ljungdahl pathway of carbon fixation of acetogenic bacteria. We developed a set of useful pathway pruning and analysis criteria to systematically assess thousands of pathways generated by BNICE.ch. Published genome-scale models of Moorella thermoacetica and Clostridium ljungdahlii were used to perform the pathway yield calculations and in-depth analyses of seven (7) newly developed biological MEG-producing pathways from gases, including CO, CO, and H. These analyses helped identify not only better candidate pathways, but also superior chassis organisms that can be used for metabolic engineering of the candidate pathways. The pathway generation, pruning, and detailed analysis procedures described in this study can also be used to develop biochemical pathways for other commodity chemicals from gaseous substrates.
一缩二乙二醇（MEG）是一种重要的石化产品，广泛应用于众多消费品中。目前的工业 MEG 生产工艺依赖于不可再生的化石燃料原料，如石油、天然气和石脑油；因此，探索从气体中合成 MEG 的替代路线是很有用的，因为它们可能为当前的生产方法提供一种更环保、更可持续的替代方案。合成生物学和微生物代谢工程技术可用于表达从气体中合成 MEG 的新生化途径，前提是首先确定有前途的替代途径。我们使用 BNICE.ch 算法，通过利用产乙酸菌的 Wood-Ljungdahl 途径固定碳，开发了从合成气中合成 MEG 的新颖的、以前未知的生物途径。我们开发了一套有用的途径修剪和分析标准，用于系统地评估 BNICE.ch 生成的数千条途径。我们使用 Moorella thermoacetica 和 Clostridium ljungdahlii 的已发表的基因组规模模型来进行途径产率计算和从气体中开发的七种（7）新的生物 MEG 生产途径的深入分析，包括 CO、CO 和 H。这些分析不仅帮助确定了更好的候选途径，还确定了可以用于候选途径代谢工程的优越底盘生物。本研究中描述的途径生成、修剪和详细分析程序也可用于从气态底物开发其他大宗商品化学品的生化途径。
