Unlocking the metabolic potential of the exceptional lignocellulose degrading fungus Parascedosporium putredinis N01

木质纤维素通过使细胞壁坚固耐用来为植物生长提供结构和支持。它是生物圈中最丰富的固定碳形式之一，其分解是全球碳循环的关键组成部分。木质纤维素还代表了一种巨大的全球糖和芳香族化合物资源，可用于生产生物燃料和化学品。生物精炼厂需要使用高产、低投入的生物质作物和/或废弃生物质作为原料;然而，木质素中存在的复杂酚类聚合物使木质纤维素对酶的攻击非常耐受。目前用于分解木质纤维素的工业方法采用多组分酶混合物。虽然这种方法在水解多糖方面是有效的，但由于需要化学密集的预处理来破坏木质素并降低纤维素的结晶度，因此效率低且昂贵。人们普遍认为，木质素的分解形成了发展具有成本竞争力的木质纤维素加工工业的最高障碍，并且该障碍将部分地通过发现用于更有效地消化原料的新酶来克服。人们还普遍认识到，如果要实现盈利，木质素的价值将是综合生物炼制的关键组成部分，因此，开发从木质素获得高价值化学品的新策略至关重要。该项目的基础是详细了解真菌Parascedosporium putredinis NO 1对木质纤维素的降解，并开始设计更有效的木质素降解和增值的工业方法。我们将进行一个令人兴奋的新的木质素酶，我们最近发现，没有一个辅因子的要求，在木质素的主要β-醚结构单元裂解的充分表征。这种酶不仅促进了商业纤维素酶混合物对生物质的分解，还从木质素大分子中释放出药学上重要的类黄酮麦黄酮，从而提供了从木质素生产有价值产品的可能性，同时降低了加工成本。我们将使用二维核磁共振来确定在消化过程中木质纤维素组成的主要变化。我们将使用比较蛋白质组学来比较P. putredinis NO1在木质素上生长的分泌组，以确定新的木质素活性酶，用于进一步研究，特别关注可能的生物精炼应用。我们将研究表达的基因和酶，以及生化过程，以确定新的酶进行研究。我们将生产这些酶的重组形式用于表征研究。我们将使用高通量分析系统来研究用于生物质加工的新酶的商业潜力。这些研究可以帮助我们了解全球碳循环的重要环境组成部分，并为我们提供新的理解和工具，以改善木质纤维素生物质的工业开发。

Lignocellulose provides structure and support to growing plants by enabling strong and durable cell walls. It is one of the most abundant forms of fixed carbon in the biosphere and its breakdown is a critical component of the global carbon cycle. Lignocellulose also represents a vast global resource of sugars and aromatics which can be liberated for the production of biofuels and chemicals. Biorefineries require the use of high yielding, low input biomass crops and/or waste biomass as feedstock; however, the complex phenolic polymers present in lignin make lignocellulose very resistant to enzymatic attack. Current industrial approaches for the breakdown of lignocellulose employ multi-component enzymatic mixtures. While this approach is effective in hydrolysing polysaccharides, it is inefficient and expensive due to the requirement of chemically-intensive pretreatments to disrupt lignin and reduce the crystallinity of cellulose. It is generally recognised that the breakdown of lignin forms the highest barrier to the development of a cost-competitive lignocellulose processing industry, and this barrier will be overcome in part by the discovery of new enzymes for more effective digestion of the feedstock. It is also generally recognised that valorisation of lignin will be a crucial component of integrated biorefineries if they are to be profitable, therefore, it is essential that new strategies for obtaining high value chemicals from lignin are developed. The basis of this project is to gain a detailed understanding of lignocellulose degradation by the fungus Parascedosporium putredinis NO1 and begin to design more efficient industrial approaches to lignin degradation and valorisation. We will carry out a full characterisation of an exciting new ligninase that we have recently discovered that cleaves the major beta-ether structural units in lignin without a requirement of a cofactor. This enzyme not only boosts the breakdown of biomass by commercial cellulase cocktails, it also releases the pharmaceutically important flavonoid tricin from the lignin macromolecule, offering the possibility of producing a valuable product from lignin while reducing the processing costs. We will use 2-dimensional NMR to identify major changes in lignocellulose composition during digestion. We will use comparative proteomics to compare the secretome of P. putredinis NO1 growing on lignin to identify new lignin active enzymes for further study with a particular focus on possible biorefining applications. We will investigate the genes and enzymes expressed, and biochemical processes, in order to identify new enzymes for study. We will produce recombinant forms of these enzymes for characterisation studies. We will use high throughput assay systems to examine the commercial potential of new enzymes for biomass processing. These studies can help us to understand important environmental components of the global carbon cycle, as well as providing us with new understanding and tools to improve the industrial exploitation of lignocellulosic biomass.