Several microorganisms can produce 2,3-butanediol (BDO), an industrially promising chemical. In this study, a Bacillus licheniformis named as 4071, was isolated from soil sample. It is a GRAS (generally recognized as safe) strain and could over-produce 2,3-BDO. Due to its mucoid forming characteristics, UV-random mutagenesis was carried out to obtain a mucoid-free strain, 4071-15. As a result, capabilities of 4071-15 strain in terms of transformation efficiency of bacillus plasmids (pC194, pUB110, and pUCB129) and fermentation performance were highly upgraded compared to those of the parent strain. In particular, 4071-15 strain could produce 123 g/L of 2,3-BDO in a fed-batch fermentation in which the ratio of (2R,3S)- to (2R,3R)-form isomers was 1:1. To increase the selectivity of (2R,3R)-BDO, budC gene was deleted by using temperature-sensitive gene deletion process via homologous recombination. The 4071-15 △budC mutant strain dramatically increased selectivity of (2R,3R)-BDO to 91% [96.3 g/L of (2R,3R)-BDO and 9.33 g/L of (2R,3S)-BDO], which was 43% higher than that obtained by the parent strain. This study has shown the potential of an isolate for 2,3-BDO production, and that the ratio of 2,3-BDO can be controlled by genetic engineering depending on its industrial usage.

中文翻译：

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工程新分离的地衣芽孢杆菌菌株，用于生产（2R，3R）-丁二醇。

几种微生物可以产生工业上有希望的化学物质2,3-丁二醇（BDO）。在这项研究中，从土壤样品中分离出了一种名为4071的地衣芽孢杆菌。这是一种GRAS（通常被认为是安全的）菌株，可能会过量生产2,3-BDO。由于其粘液样的形成特性，进行了紫外线无规诱变，获得了无粘液样的菌株4071-15。结果，与亲本菌株相比，4071-15菌株在芽孢杆菌质粒（pC194，pUB110和pUCB129）的转化效率和发酵性能方面的能力大大提高。特别地，在（2R，3S）-与（2R，3R）-形式异构体之比为1：1的补料分批发酵中，4071-15菌株可产生123g / L的2，3-BDO。为了提高（2R，3R）-BDO的选择性，通过同源重组，使用温度敏感基因缺失方法缺失了budC基因。4071-15△budC突变菌株将（2R，3R）-BDO的选择性大大提高至91％[（2R，3R）-BDO为96.3 g / L和（2R，3S）-BDO为9.33 g / L]，比亲本菌株获得的高43％。这项研究表明了分离出的2,3-BDO的潜力，并且2,3-BDO的比例可以通过基因工程控制，具体取决于其工业用途。