A novel function for the cellulose binding module of cellobiohydrolase I  

作　　者：WANG LuShan 1,2 ,ZHANG YuZhong 1 &GAO PeiJi 1 1State Key Laboratory of Microbial Technology,Shandong University,Jinan 250100,China 2Beijing Laboratory of Nanoscale Physics&Devices,Chinese Academy of Sciences,Beijing 100080,China 

出　　处：《Science China(Life Sciences)》2008年第7期620-629,共10页中国科学（生命科学英文版）

基　　金：the National Natural Science Foundation of China(Grants No.30500007);Major State Basic Research Development Research Program of China(Grant No.2004CB719702);Scientific Research Reward Fund for ExcellentYoung and Middle-Aged Scientists in Shandong Province(Grants No.2005BS06004)

摘　　要：A homogeneous cellulose-binding module(CBM)of cellobiohydrolase I(CBHI)from Trichoderma pseudokoningii S-38 was obtained by the limited proteolysis with papain and a series of chromatographs filtration.Analysis of FT-IR spectra demonstrated that the structural changes result from a weakening and splitting of the hydrogen bond network in cellulose by the action of CBMCBHI at 40℃for 24 h.The results of molecular dynamic simulations are consistent with the experimental conclusions, and provide a nanoscopic view of the mechanism that strong and medium H-bonds decreased dramatically when CBM was bound to the cellulose surface.The function of CBMCBHI is not only limited to locating intact CBHI in close proximity with cellulose fibrils,but also is involved in the structural disruption at the fibre surface.The present studies provided considerable evidence for the model of the intramolecular synergy between the catalytic domain and their CBMs.A homogeneous cellulose-binding module(CBM)of cellobiohydrolase I(CBHI)from Trichoderma pseudokoningii S-38 was obtained by the limited proteolysis with papain and a series of chromatographs filtration.Analysis of FT-IR spectra demonstrated that the structural changes result from a weakening and splitting of the hydrogen bond network in cellulose by the action of CBMCBHI at 40℃for 24 h.The results of molecular dynamic simulations are consistent with the experimental conclusions, and provide a nanoscopic view of the mechanism that strong and medium H-bonds decreased dramatically when CBM was bound to the cellulose surface.The function of CBMCBHI is not only limited to locating intact CBHI in close proximity with cellulose fibrils,but also is involved in the structural disruption at the fibre surface.The present studies provided considerable evidence for the model of the intramolecular synergy between the catalytic domain and their CBMs.

关 键 词：CELLULOSE CELLULASE CELLOBIOHYDROLASE CELLULOSE BINDING MODULE hydrogen BONDS molecular dynamics simulation 

分 类 号：Q55[生物学—生物化学]