Different effects of carbohydrate binding modules on the viscoelasticity of nanocellulose gels

Loading...
Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2020-07
Major/Subject
Mcode
Degree programme
Language
en
Pages
Series
Biochemistry and Biophysics Reports, Volume 22
Abstract
Many cellulose degrading and modifying enzymes have distinct parts called carbohydrate binding modules (CBMs). The CBMs have been shown to increase the concentration of enzymes on the insoluble substrate and thereby enhance catalytic activity. It has been suggested that CBMs also have a role in disrupting or dispersing the insoluble cellulose substrate, but dispute remains and explicit evidence of such a mechanism is lacking. We produced the isolated CBMs from two major cellulases (Cel6A and Cel7A) from Trichoderma reesei as recombinant proteins in Escherichia coli. We then studied the viscoelastic properties of native unmodified cellulose nanofibrils (CNF) in combination with the highly purified CBMs to detect possible functional effects of the CBMs on the CNF. The two CBMs showed clearly different effects on the viscoelastic properties of CNF. The difference in effects is noteworthy, yet it was not possible to conclude for example disruptive effects. We discuss here the alternative explanations for viscoelastic effects on CNF caused by CBMs, including the effect of ionic cosolutes.
Description
Keywords
CBM, Cellulose nanofibril, Family 1 carbohydrate binding module, Gel, Rheology
Other note
Citation
Rooijakkers , B J M , Arola , S , Velagapudi , R & Linder , M B 2020 , ' Different effects of carbohydrate binding modules on the viscoelasticity of nanocellulose gels ' , Biochemistry and Biophysics Reports , vol. 22 , 100766 . https://doi.org/10.1016/j.bbrep.2020.100766