来自四种不同微生物的氨酸脱酶:它们在L-氨酸生产中的表征和应用
Pengfei Gu1, Qianqian Ma2, Shuo Zhao2
1School of Biological Science and Technology, University of Jinan, Jinan, 250022, People's Republic of China. bio_gupf@ujn.edu.cn.
Biotechnology for biofuels and bioproducts
|August 3, 2023
概括
研究人员比较了四种氨酸脱酶 (AlaDH) 的L-氨酸生产. 工程大肠杆菌阻断竞争途径导致从葡萄糖获得创纪录的80.46 g/L L-alanine产量.
科学领域:
- 生物化学 生化学
- 微生物生物技术 微生物生物技术
- 酵素工程是什么? 酶工程是什么
背景情况:
- 氨酸脱酶 (AlaDH) 对于微生物代谢和L-氨酸生物合成至关重要.
- 艾拉DH酶在各种细菌物种中存在,影响着各种细胞过程.
- 亚拉DH提供了从廉价的碳来源,如葡萄糖,工业L-氨酸生产的潜力.
研究的目的:
- 评估和比较四种不同的AlaDH酶的酶性质.
- 评估这些AlaDHs在改造大肠杆菌中增强L-alanine产生的潜力.
- 开发高滴度微生物L-氨酸生产策略.
主要方法:
- 酶测定和生物化学表征的AlaDH从*细菌细菌*,*细菌大麦,**Mycobacterium smegmatis*和*Geobacillus stearothermophilus*.
- 在*大肠杆菌*BL21中表达四种AlaDH的异质表达,用于生产L-alanine.
- 大肠杆菌的代谢工程,以阻止竞争的路径L-氨酸合成.
- 料批发发酵以优化工程菌株的L-alanine生产.
主要成果:
- 在四种AlaDH之间观察到最佳温度,pH值,活性,基质亲和力和反应速率的显著差异.
- 野生型 *E. coli* 表达了从20g/L葡萄糖中产生的6.397.81g/L的L-阿兰因之间的AlaDHs.
- 经过63小时发酵后,工程*E. coli*菌株M-6实现了创纪录的80.46g/L L-alanine标位,产量为1.02g/g葡萄糖.
结论:
- 该研究提供了四种AlaDH酶的全面分析,突出了它们多样化的生物化学特性.
- 工程策略,包括途径阻断,显著提高L-氨酸的生产标位.
- 开发的高度L-氨酸生产平台显示了工业应用的潜力.
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