标题：The diversity of glycosylation of cellobiohydrolase I from Trichoderma reesei determined with mass spectrometry
作者：Wang, Mingyu; Ma, Yanan; Li, Ling; Wang, Bianfang; Wei, Xin; Zhang, Mengge; Wang, Juan; Cui, Qingyu; Li, Zhiqiang; Xu, Hai
作者机构：[Wang, Mingyu; Ma, Yanan; Li, Ling; Wang, Bianfang; Wei, Xin; Zhang, Mengge; Wang, Juan; Cui, Qingyu; Xu, Hai] Shandong Univ, Microbial Technol Inst, 更多
通讯作者：Li, ZQ;Xu, H
通讯作者地址：[Li, ZQ]Shandong Univ, Adv Res Ctr Opt, Qingdao, Shandong, Peoples R China;[Xu, H]Shandong Univ, Microbial Technol Inst, 72 Binhai Rd, Qingdao 266237, 更多
来源：BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
关键词：Trichoderma reesei; CBHI; Glycosylation; Cellulase; Mass spectrometry
摘要：Cellulases are glycosylated enzymes that have wide applications in fields like biofuels. It has been widely accepted that glycosylation of cellulases impact their performance. Trichoderma reesei is the most important cellulase-producer and cellobiohydrolase I (CBHI) is the most important cellulase from T. reesei. Therefore, the glycosylation of T. reesei CBHI has been a focus of research. However, investigations have been focused on N-glycosylation of three of the four potential glycosylation sites, as well as O-glycosylation on the linker region, while a full picture of glycosylation of T. reesei CBHI is still needed. In this work, with extensive mass spectrometric investigations on CBHI from two T. reesei strains grown under three conditions, several new discoveries were made: 1) N45 and N64 are N-glycosylated with high mannose type glycans; 2) the catalytic domain of CBHI is extensively O-glycosylated with hexoses and N-acetylhexosamines; 3) experimental evidence on the mannosylation of carbohydrate binding domain (other than the linker adjacent region) was found. With structural analysis, we found several glycosylation sites (such as T383, S8, and S46) are located at the openings of the substrate binding tunnel, and potentially involve in the binding of cellulose. These investigations provide a full and comprehensive picture on the glycosylation of CBHI from T. reesei, which benefits the engineering of CBHI by raising potential sites for modification. (C) 2018 Elsevier Inc. All rights reserved.