Investigation of a thermostable multi-domain xylanase-glucuronoyl esterase enzyme from Caldicellulosiruptor kristjanssonii incorporating multiple carbohydrate-binding modules
Artikel i vetenskaplig tidskrift, 2020

Background
Efficient degradation of lignocellulosic biomass has become a major bottleneck in industrial processes which attempt to use biomass as a carbon source for the production of biofuels and materials. To make the most effective use of the source material, both the hemicellulosic as well as cellulosic parts of the biomass should be targeted, and as such both hemicellulases and cellulases are important enzymes in biorefinery processes. Using thermostable versions of these enzymes can also prove beneficial in biomass degradation, as they can be expected to act faster than mesophilic enzymes and the process can also be improved by lower viscosities at higher temperatures, as well as prevent the introduction of microbial contamination.

Results
This study presents the investigation of the thermostable, dual-function xylanase-glucuronoyl esterase enzyme CkXyn10C-GE15A from the hyperthermophilic bacterium Caldicellulosiruptor kristjanssonii. Biochemical characterization of the enzyme was performed, including assays for establishing the melting points for the different protein domains, activity assays for the two catalytic domains, as well as binding assays for the multiple carbohydrate-binding domains present in CkXyn10C-GE15A. Although the enzyme domains are naturally linked together, when added separately to biomass, the expected boosting of the xylanase action was not seen. This lack of intramolecular synergy might suggest, together with previous data, that increased xylose release is not the main beneficial trait given by glucuronoyl esterases.

Conclusions
Due to its thermostability, CkXyn10C-GE15A is a promising candidate for industrial processes, with both catalytic domains exhibiting melting temperatures over 70 °C. Of particular interest is the glucuronoyl esterase domain, as it represents the first studied thermostable enzyme displaying this activity.

Caldicellulosiruptor kristjansonii

Lignin-carbohydrate complexes

Biomass

Carbohydrate-active enzymes

Xylan

Glucuronoyl esterase

Xylanase

Carbohydrate-binding module

Thermostability

Författare

Daniel Krska

Chalmers, Biologi och bioteknik, Industriell bioteknik

Johan Larsbrink

Chalmers, Biologi och bioteknik, Industriell bioteknik

Biotechnology for Biofuels

1754-6834 (eISSN)

Vol. 13 1 1-13

Utveckling av värmetåliga enzymblandningar

Formas, 2017-05-01 -- 2020-12-31.

Energimyndigheten, 2018-01-01 -- 2019-12-31.

Struktur-funktionstudier av enzymer som klyver bindningar mellan lignin och kolhydrater

Interreg Öresund-Kattegat-Skagerrak, 2016-12-01 -- 2017-05-31.

Interreg Öresund-Kattegat-Skagerrak, 2017-10-01 -- 2018-03-31.

Novo Nordisk Fonden, 2018-01-01 -- 2020-12-31.

Drivkrafter

Hållbar utveckling

Ämneskategorier

Industriell bioteknik

Biokemi och molekylärbiologi

Mikrobiologi

Bioteknologi med applikationer på växter och djur

Styrkeområden

Energi

Livsvetenskaper och teknik (2010-2018)

Fundament

Grundläggande vetenskaper

DOI

10.1186/s13068-020-01709-9

Mer information

Senast uppdaterat

2020-05-27