Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742, Korea.
J Microbiol Biotechnol. 2012 May;22(5):659-67. doi: 10.4014/jmb.1112.12018.
2,3-Butanediol (2,3-BDO) is an organic compound with a wide range of industrial applications. Although Escherichia coli is often used for the production of organic compounds, the wild-type E. coli does not contain two essential genes in the 2,3-BDO biosynthesis pathway, and cannot ferment 2,3-BDO. Therefore, a 2,3-BDO biosynthesis mutant strain of Escherichia coli was constructed and cultured. To determine the optimum culture factors for 2,3-BDO production, experiments were conducted under different culture environments ranging from strongly acidic to neutral pH. The extracellular metabolite profiles were obtained using high-performance liquid chromatography (HPLC), and the intracellular metabolite profiles were analyzed by ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry (UPLC/ Q-TOF-MS). Metabolic flux analysis (MFA) was used to integrate these profiles. The metabolite profiles showed that 2,3-BDO production favors an acidic environment (pH 5), whereas cell mass favors a neutral environment. Furthermore, when the pH of the culture fell below 5, both the cell growth and 2,3-BDO production were inhibited.
2,3-丁二醇（2,3-BDO）是一种具有广泛工业应用的有机化合物。尽管大肠杆菌通常用于有机化合物的生产，但野生型大肠杆菌不包含 2,3-BDO 生物合成途径中的两个必需基因，因此无法发酵 2,3-BDO。因此，构建并培养了一株 2,3-BDO 生物合成突变大肠杆菌菌株。为了确定 2,3-BDO 生产的最佳培养因素，在从强酸性到中性 pH 的不同培养环境下进行了实验。使用高效液相色谱（HPLC）获得了细胞外代谢产物图谱，并用超高效液相色谱和四极杆飞行时间质谱联用（UPLC/Q-TOF-MS）分析了细胞内代谢产物图谱。代谢通量分析（MFA）用于整合这些图谱。代谢产物图谱表明，2,3-BDO 生产有利于酸性环境（pH5），而细胞质量则有利于中性环境。此外，当培养物的 pH 降至 5 以下时，细胞生长和 2,3-BDO 生产均受到抑制。
