33 results about "Cellulosomes" patented technology

The invention discloses a method for saccharifying a cellulose raw material. A cellulosome secreted by high-temperature thermoanaerobion can effectively reduce degrade crystalline cellulose with a complex structure. By adding low concentration acetate into a culture medium and enzyme reaction buffer solution and filling low concentration hydrogen in a fermentor thereof, the method greatly improves the enzyme reaction speed and sugar accumulation. The method can make the cellulose material which is not subjected to physical or chemical pretreatment directly fermented or subjected to enzyme treatment, and efficiently hydrolyze the cellulose material into reducing sugar.

The present invention relates to an in vitro produced, artificial cellulosome for enzymatic breakdown of resilient substrates. In particular, the present invention provides a complex having an increased activity on resilient substrates, such as crystalline cellulose. The in vitro formed complex comprises a backbone scaffold having at least four binding sites capable of binding the enzyme components, whereby at least two of the binding sites have essentially the same binding specificity; and at least three different enzyme components being randomly bound to the at least four binding sites. Method for preparing the complex and uses of the same for enzymatic breakdown of resilient substrates are also provided.

The invention provides a cellulosome enzymic preparation for catalyzing saccharification of lignocellulose aiming at the problem of cellulosome in lignocellulosic saccharification in the prior art. The cellulosome enzymic preparation for catalyzing the saccharification of lignocellulose is a protein complex obtained by binding non-cellulosome proteins in cellulosome through the mutual action of non-cellulosome proteins and components in the cellulosome; then the protein complex is used for saccharifying, namely, bacterial cells are not involved in the saccharification process. The cellulosomeenzymic preparation provided by the invention not only achieves the maintenance of stability and activity, but also greatly enhances the synergistic effect with other enzymes in the system, thereby reducing the enzyme consumption, and reducing the production cost and the trivialness of the process.

The invention provides a whole-bacterium enzymic preparation for catalyzing saccharification of lignocellulose aiming at the problem of cellulosome in lignocellulosic saccharification in the prior art. The whole-bacterium enzymic preparation for catalyzing the saccharification of lignocellulose is a bacterial strain obtained after modifying cellulosome by binding cellulosome proteins in a cellulosome complex through the mutual action of non-cellulosome proteins and components in the cellulosome; then the bacterial strain is used for saccharifying, namely, bacterial cells are involved in the saccharification process. The whole-bacterium enzymic preparation provided by the invention not only achieves the maintenance of stability and activity, but also greatly enhances the synergistic effectwith other enzymes in the system, thereby reducing the enzyme consumption, and reducing the production cost and the trivialness of the process.

The invention belongs to the technical field of biology, and in particular relates to a cellulase preparation for catalyzing lignocellulose saccharification, and application of the cellulase preparation. The cellulase preparation provided by the invention contains a cellulosome complex and beta-1, 4-glucosidase at the same time, wherein the beta-1, 4-glucosidase is compounded in the cellulosome complex in a way of interaction of covalent or non-covalent proteins or fusion expression with the cellulosome complex. The cellulase preparation not only can realize high-efficiency hydrolysis of a lignocellulose substrate and has high fermentable sugar yield and saccharification rate, but also has the advantages of being low in production cost, and the like.

The present invention relates to the engineering and expression of heterologous cellulosomes in microorganisms in order to facilitate the conversion of biomass to useful products. In some embodiments, the invention relates to the expression of scaffoldin proteins which form the nucleus of a cellulosome. Cellulases or other biomass-degrading enzymes can be non-covalently linked to the scaffoldin protein by virtue of a dockerin domain-cohesin domain interaction.

The invention belongs to the technical field of resin matrix composite structure molding, and relates to a preparation method of a variable-thickness resin matrix composite structure. The variable-thickness resin matrix composite structure is prepared by adopting the following steps: forming a variable-thickness perform by means of an identical ply material thickness lamination structure, and thencuring the variable-thickness perform. The variable-thickness perform eliminates a possibility of difference between pressure fields of resin flowing or difference between cellulosome distributions in the formation of the variable-thickness perform by means of the formation of the identical ply material thickness lamination structure, a high thickness precision variable-thickness perform is obtained, and when the variable-thickness perform is hot-pressed and cured again, the resin system is in a B-stage high-viscosity state, the thickness and the precision are basically set, and high thickness precision features can be maintained, so that the high thickness precision variable thickness composite structure is finally obtained.

Provided herein are novel proteins and protein domains from newly discovered anaerobic fungal species. The anaerobic fungal species have unique enzymatic capabilities, including the ability to digest diverse lignocellulosic biomass feedstocks and to synthesize secondary metabolites. The scope of the invention encompasses novel engineered proteins comprising glycoside hydrolase enzymes, dockerin domains, carbohydrate binding domains, and polyketide synthase enzymes. The invention further encompasses artificial cellulosomes comprising novel proteins and domains of the invention. The scope of the invention further includes novel nucleic acid sequences coding for the engineered proteins of the invention, and methods of using such engineered organisms to degrade lignocellulosic biomass and to create polyketides.

A disclosed manufacturing method for negative-ion cellulosome comprises: step 1, selecting a base material, wherein the base material is a chemical fiber or cotton fiber material; step 2, preparing a nanometer tourmalinite slurry, specifically dissolving tourmalinite in water, wherein the weight ratio of tourmalinite to water is 3:5; step 3, injecting the prepared nanometer tourmalinite slurry into the base material by spraying; and step 4, drying the base material subjected to spraying injection to obtain the negative-ion cellulosome. In the step 3, the nanometer tourmalinite slurry is uniformly injected into the base material through spraying. In the step 4, air drying is employed and the drying temperature is 30-50 DEG C. The negative-ion cellulosome comprises a cellulosome body prepared from the chemical fiber or cotton fiber material, and the cellulosome body is inside provided with the nanometer tourmalinite. The beneficial effects comprise that the manufacturing method is practical, the production cost is low, the usage is convenient, and the manufactured negative-ion cellulosome is capable of effectively improving air environment around people, such as air environment in a car.

Compositions comprising unprocessed cell pellets of a cellulosome-producing microorganism grown on cellulosic biomass are provided. Further provided are methods for producing the compositions and uses thereof in hydrolysis of cellulosic substrates. In particular, the compositions advantageously contain extracellular beta-glucosidase, either expressed on the cells themselves or extrinsically added to the cell pellets.

Bacteria consume a variety of biomass-derived substrates and produce ethanol. The scaffoldin gene cipA from Clostridium thermocellum is modified to generate a mutated gene with enhanced genetic stability. This mutated cipA gene can be introduced into a heterologous host, such as Thermoanaerobacterium saccharolyticum. Other cellulosome components may be introduced into the host to build a full-sized cellulosome in T. saccharolyticum. Manipulation of the scaffoldin genes provides a new approach for enhancing ethanol production by biomass-fermenting microorganisms.

A lignocellulolytic multi-enzyme complex in the form of a cellulosome, which includes a lignin-modifying enzyme and a carbohydrate-active enzyme, is provided herewith, as well as bifunctional chimeric enzymes having lignin and cellulose / hemicellulose degrading capacity. Also provided are methods of degrading lignocellulolytic biomass, and compositions and systems for effecting the same.

The invention provides a pichia pastoris surface co-display system based on cellulosome as well as a construction method and application of the pichia pastoris surface co-display system and belongs tothe technical fields of molecular biology, food and gene engineering. The system comprises anchoring protein and polyprotein display chassis protein, wherein the anchoring protein is saccharomyces cerevisiae cell wall protein Sed1p; and the polyprotein display chassis protein is artificial mini scaffold protein MixA2 of clostridium cellulosome. The pichia pastoris surface co-display system basedon cellulosome can realize polyprotein co-display on cell surfaces; heterologous protein for fusion expression of dockerin is prepared from recombinant bacteria, purification is not needed, multiple proteins can be displayed on cell surfaces by direct specific binding of dockerin on recombinant protein and cohesion on MixA2, and the preparation cost of recombinant protein can be saved effectively.

The invention discloses a method for producing ethanol by synchronously performing steam-exploded pennisetum alopecuroides batch feeding and saccharification fermentation. The method for producing theethanol by synchronously performing steam-exploded pennisetum alopecuroides batch feeding and saccharification fermentation comprises the following steps: (1) constructing recombinant yeast cells which can co-metabolize xylose and glucose and are anchored with primary scaffold protein Scaf I; (2) assembling cellulosomes derived from cellulase and hemicellulase on the surfaces of the yeast cells so as to obtain corresponding recombinant yeast cells; (3) carrying out co-culture on the recombinant yeast cells in the step (1) and the step (2), and forming recombinant yeast cells containing composite functional cellulosomes through self-assembly of the recombinant yeast cells; and (4) inoculating the recombinant yeast cells obtained in the step (3) into a fermentation culture medium, and carrying out fermenting by using steam exploded pennisetum alopecuroides as a unique carbon source according to a batch feeding method to produce the ethanol. By utilization of the method disclosed by theinvention, the concentration of the ethanol obtained by fermentation for 96 hours can reach 2.65 g / L.

The invention provides a zymogram analysis method for semi-cellulosome analogue and belongs to the technical field of industrial biology. The method disclosed by the invention is characterized in thatthe whole analysis process is composed of three parts: electrophoresis, zymogram analysis and proteinogram analysis. A continuous gradient non-modified gel without concentrated gel is adopted for electrophoresis; an off-on probe substrate is adopted for zymogram analysis; coomassie blue staining or silver staining is adopted for proteinogram analysis. According to the method, once electrophoresisis performed while zymogram and proteinogram information of a block of gel are collected; if multienzyme complex is generated in supernatant of microorganism fermentation liquor can be quickly and effectively judged; the zymogram analysis method is developed for screening microbial strains capable of generating cellulosome compounds and can be applied to the fields of industrial bioconversion, biological energy source, medical intermediate preparation, and the like.

A multifunctional polypeptide capable of hydrolyzing cellulosic materials, xylan, and mannan is disclosed. The polypeptide includes the catalytic core (cc) of Clostridium thermocellum Cthe_0797 (CelE), the cellulose-specific carbohydrate-binding module CBM3 of the cellulosome anchoring protein cohesion region (CipA) of Clostridium thermocellum (CBM3a), and a linker region interposed between the catalytic core and the cellulose-specific carbohydrate binding module. Methods of using the multifunctional polypeptide are also disclosed.

The invention relates to mutant variants of the β-glucosidase Cgl T from Thermoanaerobacter brockii and nucleic acids for producing the same. Said mutant variants show significantly increased thermostability and enzyme activity. Furthermore, the invention provides vectors, host cells and methods for producing said mutant variants of the β-glucosidase Cgl T. Also provided are artificial cellulosomes comprising the mutant variants of the β-glucosidase Cgl T and methods for the enzymatic hydrolysis of cellulosic biomass comprising said artificial cellulosomes and / or said mutant variants of the β-glucosidase Cgl T.

The invention relates to a reconstruction method for a cellulosome gene and a new enzyme obtained through gene reconstruction, in particular relates to a gene reconstruction method based on a cellulosome and a monomeric enzyme of clostridium thermocellum and a novel lignocellulose hydrolase produced through gene reconstruction, and belongs to the field of gene engineering and enzyme engineering. A dockerin in a monomeric enzyme peptide chain of the cellulosome is excided through a gene reconstruction technology to reduce redundant components, and a CBD on a scaffolding protein is grafted to a molecule of the monomeric enzyme by a short chain to obtain a novel independent enzyme which has different molecular structures, can be independently bound with a substrate and has high activity compared with the monomeric enzyme; the invention further establishes an over-expression technology of the new enzyme. The novel cellulase NcelD without depending on a cellulosome structure is successfully obtained; the CMC hydrolysis activity and stability of the novel cellulase NcelD are improved obviously compared with a natural monomeric enzyme CelD; the NcelD coding gene obtained through gene reconstruction is subjected to soluble over-expression in a pHsh system.