铜绿假单胞菌中鼠李糖脂的强化生产及其在农业和石油工业中的应用潜力。

Enhanced production of mono-rhamnolipid in Pseudomonas aeruginosa and application potential in agriculture and petroleum industry.

机构信息

School of Life Sciences, Qufu Normal University, Qufu, Shandong Province 273165, China.

出版信息

Bioresour Technol. 2021 Mar;323:124605. doi: 10.1016/j.biortech.2020.124605. Epub 2020 Dec 31.

DOI:10.1016/j.biortech.2020.124605

Abstract

Differences in the rhamnolipid structures must result in its different activities, thus affecting its application effect. The rhlC gene in Pseudomonas aeruginosa SG was knocked out to construct strain P. aeruginosa SGΔrhlC. Rhamnolipid production was enhanced by 23.3% through knocking out rhlC gene. P. aeruginosa SGΔrhlC produced 14.22 g/L of rhamnolipid using glycerol and nitrate. Five kinds of mono-rhamnolipid but no di-rhamnolipid were produced by strain SGΔrhlC. The main rhamnolipid homologues were Rha-C-C, Rha-C-C and Rha-C-C. Mono-rhamnolipid exhibited better antimicrobial activity to Escherichia coli, Staphylococcus aureus, Aspergillus niger and Penicillium chrysogenum. Rhamnolipid produced from strain SGΔrhlC showed greater emulsifying activity to crude oil with EI of 84.73%. Rhamnolipid produced from strain SGΔrhlC efficiently washed oily sludge at 35 °C. High-producing strain P. aeruginosa SGΔrhlC and its produced mono-rhamnolipid are more promising in agriculture and petroleum industry. This study is a step forward to the tailor-made biosynthesis and application of rhamnolipid.

摘要

鼠李糖脂结构的差异必然导致其活性不同，从而影响其应用效果。敲除铜绿假单胞菌 SG 中的 rhlC 基因构建了 P. aeruginosa SGΔrhlC 菌株。通过敲除 rhlC 基因，鼠李糖脂的产量提高了 23.3%。铜绿假单胞菌 SGΔrhlC 利用甘油和硝酸盐生产 14.22 g/L 的鼠李糖脂。SGΔrhlC 菌株产生的 5 种单鼠李糖脂，但没有二鼠李糖脂。主要的鼠李糖脂同系物为 Rha-C-C、Rha-C-C 和 Rha-C-C。单鼠李糖脂对大肠杆菌、金黄色葡萄球菌、黑曲霉和产黄青霉表现出更好的抗菌活性。SGΔrhlC 菌株产生的鼠李糖脂对原油具有更高的乳化活性，EI 为 84.73%。SGΔrhlC 菌株产生的鼠李糖脂在 35°C 下能有效地清洗含油污泥。高产菌株 P. aeruginosa SGΔrhlC 及其产生的单鼠李糖脂在农业和石油工业中更有应用前景。本研究朝着鼠李糖脂的定制生物合成和应用迈出了一步。