INTERACTIONS BETWEEN ENZYMES AND CELLULOSE MODEL FILMS UNVEILED BY QCM-D TECHNIQUE

摘要

To understand the mechanism of cellulose hydrolysis and super strength of protein-cellulose hybrid composites,it is necessary to study the interactions between enzymes and cellulose substrates.In this investigation,impacts of substrate polymorphs on the adsorption of cellulases were investigated by QCM-D technique.Initially,cellulose model films with allomorphs of Ⅰ,Ⅱ and the hybrid were prepared.It followed the adsorption of Trichoderma reesei on model cellulose films monitored by QCM-D technique.The results showed that cellulose nanocrystal with allomorph Ⅱ(CNC-Ⅱ)had the lowest adsorption capacity with the total amount of 179.20 ng·cm-2,but the highest reversible binding ratio of 33.72％.Whereas CNC-Ⅱ presented the fastest enzymatic hydrolysis.What's more,the conformation of adsorbed enzyme layer on CNC-Ⅱ substrate was softer and looser than those on CNC-Ⅰ and the hybrid substrates.The results indicated that the polymorphism of cellulose has a very important impact on the reversible adsorbed amount of enzymes and the conformation of adsorbed enzyme layers on cellulose substrate; it is maybe the reason why it has the greatest effect on hydrolysis speed,if compared with enzyme adsorption amount and substrate's crystallinity degree.