Influence of Linker Length Variations on the Biomass-Degrading Performance of Heat-Active Enzyme Chimeras.
Plant cell walls are composed of complex polysaccharides such as cellulose and hemicellulose. In order to efficiently hydrolyze cellulose, the synergistic action of several cellulases is required. Some anaerobic cellulolytic bacteria form multienzyme complexes, namely cellulosomes, while other microorganisms produce a portfolio of diverse enzymes that work in synergistic fashion. Molecular biological methods can mimic such effects through the generation of artificial bi- or multifunctional fusion enzymes. Endoglucanase and β-glucosidase from extremely thermophilic anaerobic bacteria Fervidobacterium gondwanense and Fervidobacterium islandicum, respectively, were fused end-to-end in an approach to optimize polysaccharide degradation. Both enzymes are optimally active at 90 °C and pH 6.0-7.0 representing excellent candidates for fusion experiments. The direct linkage of both enzymes led to an increased activity toward the substrate specific for β-glucosidase, but to a decreased activity of endoglucanase. However, these enzyme chimeras were superior over 1:1 mixtures of individual enzymes, because combined activities resulted in a higher final product yield. Therefore, such fusion enzymes exhibit promising features for application in industrial bioethanol production processes.
['Rizk|Mazen|M|', 'Antranikian|Garabed|G|', 'Elleuche|Skander|S|']
D001426:Bacterial Proteins D018533:Biomass D002384:Catalysis D002480:Cellulase D016965:Gram-Negative Anaerobic Straight, Curved, and Helical Rods D011993:Recombinant Fusion Proteins D013379:Substrate Specificity D013696:Temperature D001617:beta-Glucosidase
Linkers Endoglucanase β-Glucosidase Gene fusions Glucose yield Synergism Thermozymes