为了建立有效的饲用木质纤维素酶系协同作用的技术体系，提高粗纤维的降解率，缓解饲料资源紧张的现状，本项目拟以课题组前期克隆的高活性纤维素外切酶基因(cen6)、内切酶基因(cex6)、纤维二糖酶基因(bg6)和木聚糖酶基因(xyn)为元件，构建含有锚定域的重组纤维素酶基因，并利用来源于厌氧微生物的粘附域基因进行脚手架蛋白基因的人工设计和构建；利用课题组前期建立的探测载体pShuttle筛选强启动子，构建枯草芽孢杆菌高效表达系统，对得到的重组纤维素酶基因和脚手架蛋白基因进行表达，锚定域和粘附域的特异性结合，介导组装纤维素酶多酶复合体，通过其在物理空间上的协同作用，有效降解木质纤维素。通过本项目的实施，建立一套枯草芽孢杆菌纤维素酶多酶复合体的高表达系统，研究和筛选纤维素酶系成员之间，以及它们与木聚糖酶之间的协同作用效果，以提高粗纤维的降解率，从而为饲用纤维素的高效利用提供新的理论依据和技术体系。

For improving utilization of fiber and exploiting the feed resource, we will developed the engineering cellulosomal Bacillus subtilis in this project. To construct the the cellulase gene and xylanse gene containning dockerine module, the coding genes of cen6, cex6, bg6 and xyn will be employed to link with the coding gene of type I dockerin module, resulting cen6dR、cex6dC、bg6 and xyndB. Meanwhile, the coding genes of scaffoldin will be assembled by coding gene of cohesin module and cabohydrate binding module. The strong promoter will be cloned by using of promoter-trapping system, and high-level expression system will be developed by the resultant strong promoter in Bacillus subtilis. Through high-level expression of cen6dR、cex6dC、bg6dA, xyndB and coding genes of scaffoldin, three engineered designer cellolusome will be obtained. The cellulase-cellulase and cellulase-xylanase synergy will be investigated. Thus, this would provide an efficient engineering cellulosomal Bacillus subtilis and a potential method and approach for efficient utilization of fiber.