State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing, China.
Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico.
Microb Biotechnol. 2023 Feb;16(2):381-391. doi: 10.1111/1751-7915.14118. Epub 2022 Aug 3.
The economical production of 5-aminolevulinic acid (ALA) has recently received increasing attention for its extensive use in agriculture. In this study, a strain of Bacillus cereus PT1 could initially produce ALA at a titre of 251.72 mg/L by using a hydrolysate mixture of low-cost cassava residue and fish waste. The integration of endogenous hemA encoding glutamyl-tRNA reductase led to a 39.30% increase in ALA production. Moreover, improving cell permeability by deletion of the LytR-CpsA-Psr (LCP) family gene tagU led to a further increase of 59.73% in ALA production. Finally, the engineered strain B. cereus PT1-hemA-ΔtagU produced 2.62 g/L of ALA from the previously mentioned hydrolysate mixture in a 7-L bioreactor. In a pot experiment, foliar spray of the ALA produced by B. cereus PT1-hemA-ΔtagU from the hydrolysates increased salt tolerance of cucumber by improving chlorophyll content and catalase activity, while decreasing malondialdehyde content. Overall, this study demonstrated an economic way to produce ALA using a microbial platform and evidenced the potential of ALA in agricultural application.
5-氨基乙酰丙酸（ALA）的经济生产因其在农业中的广泛应用而受到越来越多的关注。在这项研究中，蜡状芽孢杆菌 PT1 菌株最初可以利用低成本木薯渣和鱼废物的水解混合物生产 251.72mg/L 的 ALA。整合内源性 hemA 编码谷氨酰-tRNA 还原酶可使 ALA 产量增加 39.30%。此外，通过缺失 LytR-CpsA-Psr (LCP) 家族基因 tagU 来提高细胞通透性，可使 ALA 产量进一步增加 59.73%。最后，工程菌株 B. cereus PT1-hemA-ΔtagU 从上述水解混合物中在 7L 生物反应器中生产了 2.62g/L 的 ALA。在盆栽试验中，蜡状芽孢杆菌 PT1-hemA-ΔtagU 从水解物中产生的 ALA 叶面喷施可通过提高叶绿素含量和过氧化氢酶活性，同时降低丙二醛含量来提高黄瓜的耐盐性。总的来说，本研究利用微生物平台展示了一种经济的生产 ALA 的方法，并证明了 ALA 在农业应用中的潜力。
