改造细胞质膜促进途径酶组装及N-乙酰氨基葡萄糖合成

Engineering Plasma Membrane to Promote Enzyme Assembly and N-Acetylglucosamine Synthesis

摘要:

功能膜微域（FMMs）可以作为内源性空间支架进行途径酶组装，适度地提高FMMs在质膜中的占比能够明显提高产物合成量，然而对FMMs进行改造后，细胞生长和产物的合成均受到抑制。在课题组前期研究的基础上，对细胞质膜进行理性改造以缓解FMMs过度改造对细胞造成的影响。首先通过过表达PlsX，PlsY和PlsC改造细胞质膜，之后，以枯草芽孢杆菌合成N-乙酰氨基葡萄糖（GlcNAc）为例，发现质膜改造的菌株中GlcNAc产量达到（5.18±0.16） g/L，与对照菌株相比产量提升了41.9%，同时，细胞质膜改造也明显降低FMMs过度修饰对菌株生长产生的不利影响。

Abstract:

Functional membrane microdomains(FMMs) can be used as the endogenous spatial scaffolds for pathway enzyme assembly. Moderately increasing the proportion of FMMs in plasma membrane can significantly increase the synthesized product yield. However, the cell growth and product synthesis were both inhibited after further modification of FMMs. Based on the previous research of our group, the rational modification of plasma membrane was carried out to alleviate the effects of excessive FMMs modification on cells. First, the plasma membrane was rationally engineered by overexpression of PlsX, PlsY and PlsC. Then, taking the synthesis of N-acetylglucosamine(GlcNAc) by Bacillus subtilis as an example, it was found that GlcNAc titer in the plasma lemma-modified strains was （5.18±0.16） g/L, which was almost 41.9% higher than that of the control strain. In addition, cell membrane modification also reduced the adverse effect of FMMs over modification on the growth of the strain.