Cellobiose dehydrogenase

About: Cellobiose dehydrogenase is a research topic. Over the lifetime, 516 publications have been published within this topic receiving 21502 citations.

Degradation of cellulose by basidiomycetous fungi.

Abstract: Cellulose is the main polymeric component of the plant cell wall, the most abundant polysaccharide on Earth, and an important renewable resource. Basidiomycetous fungi belong to its most potent degraders because many species grow on dead wood or litter, in environment rich in cellulose. Fungal cellulolytic systems differ from the complex cellulolytic systems of bacteria. For the degradation of cellulose, basidiomycetes utilize a set of hydrolytic enzymes typically composed of endoglucanase, cellobiohydrolase and β-glucosidase. In some species, the absence of cellobiohydrolase is substituted by the production of processive endoglucanases combining the properties of both of these enzymes. In addition, systems producing hydroxyl radicals based on cellobiose dehydrogenase, quinone redox cycling or glycopeptide-based Fenton reaction are involved in the degradation of several plant cell wall components, including cellulose. The complete cellulolytic complex used by a single fungal species is typically composed of more than one of the above mechanisms that contribute to the utilization of cellulose as a source of carbon or energy or degrade it to ensure fast substrate colonization. The efficiency and regulation of cellulose degradation differs among wood-rotting, litter-decomposing, mycorrhizal or plant pathogenic fungi and yeasts due to the different roles of cellulose degradation in the physiology and ecology of the individual groups.

Enzymatic conversion of biomass for fuels production.

Abstract: Bioconversion for Production of Renewable Transportation Fuels in the United States: A Strategic Perspective Cellulase and Xylanase Systems of Thermotoga neapolitana Structure-Function Studies of Endo-1,4-*b-D-glucanase E2 from Thermomonospora fusca Role of Cellulose-Binding Domain of Cellobiohydrolase I in Cellulose Hydrolysis CelS: A Major Exoglucanese Component of Clostridium thermocellum Cellulosome Plant Endo-1,4-*b-D-glucanases: Structure, Properties, and Physiological Function Approaches to Cellulase Purification Cellobiose Dehydrogenase: A Hemoflavoenzyme from Phanerochaete chrysoporium Cellulase Production Technology: Evaluation of Current Status Cellulase Assays: Methods from Empirical Mathematical Models Components of Trichoderma reesei Cellulase Complex on Crystalline Cellulose: Three-Dimensional Visualization with Colloidal Gold Deposition of Metallic Platinum in Blue-Green Algae Cells Genetic Engineering Approaches for Enhanced Production of Biodiesel Fuel from Microalgae Microbial and Enzymatic Biofuel Cells Pretreatment of Lignocellulosic Biomass Bioconversion of Wood Residues: Mechanisms Involved in Pretreating and Hydrolyzing Lignocellulosic Materials Development of Genetically Engineered Microorganisms for Ethanol Production Kinetic Consequences of High Ratios of Substrate to Enzyme Saccharification Systems Based on Trichoderma Cellulase Pectin-Rich Residues Generated by Processing of Citrus Fruits, Apples, and Sugar Beets: Enzymatic Hydrolysis and Biological Conversion to Value-Added Products Silage Processing of Forage Biomass to Alcohol Fuel Conversion of Hemicellulose Hydrolyzates to Ethanol Anaerobic Digestion of Municipal Solid Waste: Enhanced Cellulolytic Capacity Through High-Solids Operation Compared to Conventional Low-Solids Systems Role of Acetyl Esterase in Biomass Conversion Metabolism of Xylose and Xylitol by Pachysolen tannophilus

Cellobiose Dehydrogenase and a Copper-Dependent Polysaccharide Monooxygenase Potentiate Cellulose Degradation by Neurospora crassa

Abstract: The high cost of enzymes for saccharification of lignocellulosic biomass is a major barrier to the production of second generation biofuels. Using a combination of genetic and biochemical techniques, we report that filamentous fungi use oxidative enzymes to cleave glycosidic bonds in cellulose. Deletion of cdh-1, the gene encoding the major cellobiose dehydrogenase of Neurospora crassa, reduced cellulase activity substantially, and addition of purified cellobiose dehydrogenases from M. thermophila to the Δcdh-1 strain resulted in a 1.6- to 2.0-fold stimulation in cellulase activity. Addition of cellobiose dehydrogenase to a mixture of purified cellulases showed no stimulatory effect. We show that cellobiose dehydrogenase enhances cellulose degradation by coupling the oxidation of cellobiose to the reductive activation of copper-dependent polysaccharide monooxygenases (PMOs) that catalyze the insertion of oxygen into C–H bonds adjacent to the glycosidic linkage. Three of these PMOs were characterized and s...

Oxidative cleavage of cellulose by fungal copper-dependent polysaccharide monooxygenases.

Abstract: Fungal-derived, copper-dependent polysaccharide monooxygenases (PMOs), formerly known as GH61 proteins, have recently been shown to catalyze the O2-dependent oxidative cleavage of recalcitrant polysaccharides. Different PMOs isolated from Neurospora crassa were found to generate oxidized cellodextrins modified at the reducing or nonreducing ends upon incubation with cellulose and cellobiose dehydrogenase. Here we show that the nonreducing end product formed by an N. crassa PMO is a 4-ketoaldose. Together with isotope labeling experiments, further support is provided for a mechanism involving oxygen insertion and subsequent elimination to break glycosidic bonds in crystalline cellulose.