米根黴菌(Rhizopus oryzae)之葡糖澱粉水解酵素(glucoamylase, GA)為含有579個胺基酸之醣類水解酶，其結構包括澱粉吸附區(starch-binding domain, RoSBD)、酵素催化區及一段高度醣基化的連接片段。醣類吸附模組(carbohydrate-binding module, CBM)對於不溶性多醣之水解具重要調節功能，本研究以隸屬醣類吸附模組家族二十一的RoSBD為材料進行研究。CBM之結構和免疫球蛋白具有高度相似性，並與多種具有辨識致病菌能力之凝集素同富含高度β-strand 之二級結構，顯示CBM可能與免疫球蛋白具演化相關性及功能類似性。另外，於CBM家族中亦發現部分成員具有和細胞表面醣蛋白結合的功能，進一步觀察此類CBM，發現其結構多由數個CBM串接，形成多價性蛋白構型。多價性蛋白與其配體之結合力遠大於單價性蛋白，現今常利用此觀念將標的蛋白與具有多聚體能力之蛋白(Multivalent protein binder)以分子工程方式結合表現，以提升標的蛋白作用能力。本研究將具雙聚能力之抗體Fc部位及具三聚能力之膠原蛋白類似胜肽(CLP)個別與RoSBD結合，成功於大腸桿菌表現及利用親和性管柱層析純化穩定的新穎重組蛋白質，並以非變性凝膠電泳分析、超高速離心、及分子篩層析法確認多價體蛋白質特性。以depletion isotherm assay 及Isothermal Titration Calorimetry (ITC)方法檢測，發現多價性RoSBD對於長鏈醣類之結合能力大幅提升，且其對於固態和液態之配體可能具有不同的結合機制。本研究除深入了解醣類吸附模組的特性及功能，亦進一步運用重組蛋白質工程創造新穎的多價性蛋白，未來將有機會應用於病原體的偵測或成為一種創新的殺菌劑。

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