从乳酸细菌中雅克中表达β-葡萄糖酶:一种基因工程方法
Chuan Wang1,2, Yuze Yang3, Chunjuan Ma1
1College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China.
Microorganisms
|June 28, 2023
概括
经过工程设计的乳酸细菌表达了雅克鲁门β-葡萄糖酶子单元,显示出高酶活性. 化蛋白Bgl的活性明显高于单个子单元,显示出工业纤维素水解的潜力.
科学领域:
- 生物技术是生物技术.
- 酶学 是一种酶学.
- 微生物工程 微生物工程
背景情况:
- 微生物β-葡萄糖酶对于工业应用至关重要.
- 雅克的β-葡萄糖酶子单元 (bglA和bglB) 被研究了增强表达.
研究的目的:
- 为了构建基因工程乳酸细菌 (Lactobacillus lactis NZ9000) 的高效β-葡萄糖酶生产.
- 为了比较独立和化β-葡萄糖酶子单元的酶活性.
主要方法:
- 在L. lactis NZ9000.中表达了两种亚基单元 (bglA,bglB) 的雅克皮β-葡萄糖酶,它们独立表达,并作为化蛋白质.
- 实现了BglA,BglB和化Bgl的分泌表达.
- 分析了酶活性,动力参数和在不同条件下的稳定性.
主要成果:
- 已经成功地构建了L. lactis NZ9000/pMG36e-usp45-bglA,L. lactis NZ9000/pMG36e-usp45-bglB和L. lactis NZ9000/pMG36e-usp45-bglA-usp45-bglB的工程菌株.
- 化蛋白Bgl显示显著更高的酶活性 (9.4 U/mL) 与单个子单位BglA (2.09 U/mL) 和BglB (2.36 U/mL) 相比,在1%的沙利辛.
- 所有酶的最佳条件是50°C和pH值7.0,其中1%的沙利辛是最合适的基质.
结论:
- 改造的L. lactis菌株有效地产生β-葡萄糖酶,而化蛋白质表现出优越的活性.
- 这些发现为β-葡萄糖酶在纤维素水解中的工业应用提供了基础.
- 这项研究强调了基因工程在增强生物技术目的酶生产方面的潜力.
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