The binding of cellulase variants to dislocations: a semi-quantitative analysis based on CLSM (confocal laser scanning microscopy) images
Journal article, 2015

© 2015, Hidayat et al. Binding of enzymes to the substrate is the first step in enzymatic hydrolysis of lignocellulose, a key process within biorefining. During this process elongated plant cells such as fibers and tracheids have been found to break into segments at irregular cell wall regions known as dislocations or slip planes. Here we study whether cellulases bind to dislocations to a higher extent than to the surrounding cell wall. The binding of fluorescently labelled cellobiohydrolases and endoglucanases to filter paper fibers was investigated using confocal laser scanning microscopy and a ratiometric method was developed to assess and quantify the abundance of the binding of cellulases to dislocations as compared to the surrounding cell wall. Only Humicola insolens EGV was found to have stronger binding preference to dislocations than to the surrounding cell wall, while no difference in binding affinity was seen for any of the other cellulose variants included in the study (H. insolens EGV variants, Trichoderma reesei CBHI, CBHII and EGII). This result favours the hypothesis that fibers break at dislocations during the initial phase of hydrolysis mostly due to mechanical failure rather than as a result of faster degradation at these locations.

Dislocations

Confocal laser scanning microscopy

Cellulase binding

Semi-quantitative analysis

Fluorescence-labelled enzymes

Ratio imaging

Author

B.J. Hidayat

Unicon

C. Weisskopf

Max Planck Institute

C. Felby

University of Copenhagen

Katja Salomon Johansen

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

L.G. Thygesen

University of Copenhagen

AMB Express

2191-0855 (ISSN)

Vol. 5 1 1-14

Driving Forces

Sustainable development

Areas of Advance

Energy

Subject Categories

Biocatalysis and Enzyme Technology

DOI

10.1186/s13568-015-0165-9

More information

Latest update

9/6/2018 1