Development of enzymatic pulp and paper applications

加拿大是世界上最大的纸浆和纸制品出口国。该行业雇用了大约70，000名加拿大人，对该国的经济具有战略重要性。为了保持其全球竞争力，该行业已经确定了生物催化剂干预的三个过程：漂白，制浆和去除木材提取物。在这些工艺中增加使用生物催化剂（酶）有望降低生产成本，使不利的环境影响最小化，降低能耗，并产生上级纸产品。白腐真菌以其完全水解木材的能力而闻名。黄孢原毛平革菌是研究最深入的白腐真菌。这种真菌或从中分离的胞外酶已用于木材的制浆和漂白。然而，用于木材提取物的有效漂白、制浆和水解的酶组合尚未完全了解。黄孢原毛平革菌的基因组最近已完全测序和注释。我们已经构建了一个代表这个物种5,000多个基因的DNA微阵列。这些基因组资源的可用性提供了参与木材降解的基因的系统分析。我们建议检查的基因表达谱的P. chrysosporium的条件下，促进漂白，制浆和水解的木材提取物。将克隆编码在上述条件下上调的细胞外蛋白的基因并在稳健的细胞工厂中表达。将对重组蛋白进行生物化学表征。它们也将单独测试和组合测试其在纸浆和造纸工艺中的效用。从拟议的研究结果将大大提高我们的知识的生物降解的木材。它们还将用于指导纸浆和造纸工业新型酶应用的开发。

Canada is the largest exporter of pulp and paper products in the world. Employing about 70,000 Canadians, this industry is of strategic importance to the economy of the country. To maintain its global competitiveness, the industry has identified among others three processes for biocatalyst intervention: bleaching, pulping, and removal of wood extractives. The increased use of biocatalysts (enzymes) in these processes are expected to reduce the cost of production, minimize adverse environmental impact, lower the consumption of energy, and yield superior paper products. White-rot fungi are known for their ability to completely hydrolyze wood. Phanerochaete chrysosporium is the most intensively studied white-rot fungus. This fungus or extracellular enzymes isolated from it has been used for pulping and bleaching of wood. However, the enzyme combinations for efficient bleaching, pulping, and hydrolysis of wood extractives are not fully understood. The genome of P. chrysosporium has recently been completely sequenced and annotated. We have constructed a DNA microarray representing over 5,000 genes of this species. The availability of these genomic resources affords the systematic analysis of genes involved in wood degradation. We propose to examine the gene expression profiles of P. chrysosporium under conditions that promote bleaching, pulping, and hydrolysis of wood extractives. Genes encoding extracellular proteins that are up-regulated under the above conditions will be cloned and expressed in a robust cell factory. The recombinant proteins will be characterized biochemically. They will also be tested individually and in combination for their utility in pulp and paper processes. Results from the proposed research will enhance significantly our knowledge of biological degradation of wood. They will also be used to guide the development of novel enzyme applications for the pulp and paper industry.