Abstract Bacterial cellulose consisting of pure cellulose nanofibers, is a promising biomaterial with versatile applications. The primary producer is Komagataeibacter xylinus, however, its use is limited because the bacteria undergo irreversible conversion into a non-cellulose-producing mutant (Cel-) during shaking cultivation. Here, by investigating the bcs operon in Cel- mutants, we found that an IS element-inserted mutation in bcsA, is responsible for the conversion into Cel-. To prevent IS element insertion into bcsA, putative IS element recognition sequences were modified. As a result, the engineered strain retained its own bcsA gene over seven sub-cultivations, and showed 1.7-fold higher productivity than wild-type strains without any differences of physical and chemical properties.

中文翻译：

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通过阻止 IS 元件插入纤维素合成基因，提高木曲杆菌中纤维素的生产

摘要 由纯纤维素纳米纤维组成的细菌纤维素是一种具有广泛应用前景的生物材料。主要生产者是 Komagataeibacter xylinus，然而，它的使用受到限制，因为该细菌在振荡培养过程中会发生不可逆的转化为不产生纤维素的突变体 (Cel-)。在这里，通过研究 Cel- 突变体中的 bcs 操纵子，我们发现 bcsA 中插入 IS 元件的突变负责转化为 Cel-。为了防止 IS 元素插入 bcsA，修改了假定的 IS 元素识别序列。结果，工程菌株在 7 次亚培养中保留了自己的 bcsA 基因，并且显示出比野生型菌株高 1.7 倍的生产力，而没有任何物理和化学性质的差异。