PDF(Pubmed)
Abstract：
The establishment of sustainable processes for the production of commodity chemicals is one of today\'s central challenges for biotechnological industries. The chemo-autotrophic fixation of CO2 and the subsequent production of acetate by acetogenic bacteria via anaerobic gas fermentation represents a promising platform for the ecologically sustainable production of high-value biocommodities via sequential fermentation processes. In this study, the applicability of acetate-containing cell-free spent medium of the gas-fermenting acetogenic bacterium A. woodii WP1 as the feeder strain for growth and the recombinant production of P. aeruginosa PAO1 mono-rhamnolipids in the well-established nonpathogenic producer strain P. putida KT2440 were investigated. Additionally, the potential possibility of a simplified production process without the necessary separation of feeder strain cells was elucidated via the cultivation of P. putida in cell-containing A. woodii culture broth. For these cultures, the content of both strains was investigated by examining the relative quantification of strain-exclusive genes via qPCR. The recombinant production of mono-rhamnolipids was successfully achieved with maximum titers of approximately 360-400 mg/L for both cell-free and cell-containing A. woodii spent medium. The reported processes therefore represent a successful proof of principle for gas fermentation-derived acetate as a potential sustainable carbon source for future recombinant rhamnolipid production processes by P. putida KT2440.
摘要：
建立用于生产商品化学品的可持续过程是当今生物技术行业的主要挑战之一。CO2的化学自养固定以及随后通过厌氧气体发酵由产乙酸细菌产生乙酸盐代表了通过顺序发酵过程在生态上可持续生产高价值生物商品的有希望的平台。在这项研究中,研究了在建立良好的非致病性生产菌株P.putidaKT2440中，含乙酸盐的无细胞废培养基作为生长和重组生产铜绿假单胞菌PAO1单鼠李糖脂的饲养菌株的适用性。此外,通过在含有细胞的A.woodii培养肉汤中培养恶臭假单胞菌，阐明了简化生产过程的潜在可能性，而无需必要分离饲养菌株细胞。对于这些文化,通过qPCR检查菌株排他性基因的相对定量来研究两个菌株的含量。对于无细胞和含细胞的A.woodii用过的培养基,以大约360-400mg/L的最大滴度成功地实现了单鼠李糖脂的重组生产。因此,所报道的方法代表了气体发酵衍生的乙酸盐作为由恶臭假单胞菌KT2440进行的未来重组鼠李糖脂生产工艺的潜在可持续碳源的原理的成功证明。
