Microbial conversion of lignin to monomers for bio-based plastics using synthetic biology (MILIMO)

欧盟国家的社会需要开发新型生物塑料，以取代目前的石油基塑料，用于一系列包装应用。该项目的工业合作伙伴Biome Bioplastics Ltd（英国）一直在开发新的聚酯塑料，其中含有用于石油基塑料（如PET或PBAT）的对苯二甲酸的替代品。Bugg教授和Biome Bioplastics开发了一种生物催化路线，从植物细胞壁中发现的生物聚合物木质素到2，4-和2，5-吡啶二羧酸，可用作对苯二甲酸的生物基替代品。该项目将寻求从木质素中提高2，4-PDCA和2，5-PDCA的产率，以开发商业上可行的生产方法。 该项目将使用合成生物学方法来提高两种木质素降解细菌：Rhodococcus jostii RHA 1和Pseudomonas putida KT 2440中的木质素氧化速率。我们还将致力于将羟基肉桂酸或木质纤维素的纤维素部分转化为PDCA单体。合成生物学还将用于重新设计恶臭假单胞菌KT 2440的代谢途径，以优化来自不同植物原料的PDCA单体的生产。 我们还将研究使用不同的木质纤维素降解细菌的财团将木质素转化为PDCA单体，模仿土壤中的情况，其中木质素降解专家和纤维素降解专家的财团合作，以分解木质纤维素生物质。 在开发了一种在实验室条件下小规模生产PDCA的高产工艺后，生物催化工艺将扩大规模，以产生一种有效的基于发酵的方法，用于将木质素或木质纤维素原料转化为PDCA单体，该方法可以由Biome Bioplastics商业化。

There is a societal need in EU countries to develop new types of bio-plastics that could be used to replace current petroleum-based plastics for a range of packaging applications. The industrial partner in this Project, Biome Bioplastics Ltd (UK), has been developing new polyester plastics containing replacements for terephthalic acid used in petroleum-based plastics such as PET or PBAT. Professor Bugg and Biome Bioplastics have developed a biocatalytic route from the biopolymer lignin, found in plant cell walls, to 2,4- and 2,5-pyridinedicarboxylic acid, which can be used as biobased replacements for terephthalic acid. This project will seek to enhance the yields of 2,4-PDCA and 2,5-PDCA from lignin, to the point where a commercially feasible method of production could be developed. The project will use synthetic biology methods to enhance the rate of lignin oxidation in two lignin-degrading bacteria: Rhodococcus jostii RHA1 and Pseudomonas putida KT2440. We will also aim to convert hydroxycinnamic acids or the cellulose fraction of lignocellulose into PDCA monomers. Synthetic biology will also be used to redesign the metabolic pathways of Pseudomonas putida KT2440 in order to optimise the production of PDCA monomers from different plant feedstocks. We will also investigate the use of consortia of different lignocelluose-degrading bacteria for the conversion of lignin into PDCA monomers, mimicking the situation in soil where consortia of lignin-degrading specialists and cellulose-degrading specialists co-operate in order to break down lignocellulosic biomass. Having developed a high-yield process for production of PDCAs on a small scale under laboratory conditions, the biocatalytic process will be scaled up to yield an efficient fermentation-based method for conversion of lignin or lignocellulose feedstocks to PDCA monomers, that could be commercialised by Biome Bioplastics.