Mackenzie Katherine J, Francis Matthew B
Department of Chemistry and Energy Biosciences Institute, University of California, Berkeley, California, 94720.
Biotechnol Bioeng. 2014 Sep;111(9):1792-800. doi: 10.1002/bit.25252. Epub 2014 Jul 4.
There is currently much interest in the economic use of cellulosic biomass as a source of renewable fuels. This process typically involves the enzymatic hydrolysis of plant matter to afford soluble sugars for subsequent fermentation steps. The cost of cellulase enzymes presents a critical barrier to the commercialization of these processes. In this work, we demonstrate that a new family of polymer additives based on NIPAm can increase enzyme performance substantially. When applied to an industrially relevant combination of enzymes and lignin-containing biomass, polymer additives allow a 60% reduction in enzyme loading to achieve the same level of saccharification. Evidence presented herein suggests that these polymers function through multiple mechanisms, including (1) preventing enzyme denaturation through shear and interfacial interactions, (2) preventing non-productive adsorption to lignin, and (3) altering the cellulose structure. An advantage of these polymers over other additives is their thermoresponsive behavior, enabling their recovery and reuse.
目前，人们对将纤维素生物质作为可再生燃料来源进行经济利用有着浓厚兴趣。该过程通常涉及植物物质的酶促水解，以提供可溶性糖用于后续发酵步骤。纤维素酶的成本是这些过程商业化的关键障碍。在这项工作中，我们证明了基于NIPAm的新型聚合物添加剂家族可以显著提高酶的性能。当应用于工业相关的酶和含木质素生物质的组合时，聚合物添加剂可使酶负载量降低60%，以达到相同的糖化水平。本文提供的证据表明，这些聚合物通过多种机制发挥作用，包括：（1）通过剪切和界面相互作用防止酶变性；（2）防止与木质素的非生产性吸附；（3）改变纤维素结构。这些聚合物相对于其他添加剂的一个优点是它们的热响应行为，使其能够回收和再利用。
