13 results about "Exoxylanase activity" patented technology

The invention discloses xylanase XynA00838, a truncated body of the xylanase XynA00838 for removing CBM1 and application of the xylanase XynA00838, and belongs to the technical field of microorganisms. The invention provides the XynA00838, the amino acid sequence of the truncation of the XynA00838 and the nucleotide sequence of the coding gene of the XynA00838, and provides characterization information, the XynA00838 and the truncation of the XynA00838 have obvious xylanase activity, and the specific enzyme activity of the truncation of the XynA00838 is obviously higher than that of wild type xylanase XynA00838 when six different plant polysaccharides are degraded, so that the XynA00838 and the truncation of the XynA00838 can be used for degrading various plant polysaccharides. When the truncated body degrades low-viscosity wheat arabinoxylan as a substrate, the specific enzyme activity reaches 4.46 + / -0.12 U / mg and is remarkably higher than that of wild type xylanase XynA00838. The CBM1 in the xylanase XynA00838 disclosed by the invention has a relatively good maintaining effect on the temperature stability of an enzyme catalysis module of the xylanase XynA00838. The truncated body XynA00838 delta CBM1 of the xylanase XynA00838 without the CBM1 has high enzyme activity and pH stability, so that the truncated body XynA00838 delta CBM1 has relatively great development and application potential, and a basic theoretical basis is provided for preparing a commercial feed enzyme preparation.

A variant polypeptide of xylanase, and a fusion protein and an enzyme composition comprising the variant polypeptide, a recombinant host cell for production of the variant polypeptide, methods for using it and its use, is disclosed comprising an amino acid sequence having at least 79%, but less than 100% amino acid sequence identity with amino acids 1-191 of SEQ ID NO: 1, wherein the amino acid sequence has xylanase activity, at least one disulfide bridge between two Cys residues in the 1-191 amino acid region, and an amino acid substitution at the position 23 or 28, or at the positions 23 and 28, the positions corresponding to the positions 23 and 28 of the SEQ ID NO: 1.

The present disclosure relates to a modified polypeptide having xylanase activity and the use thereof.

The invention belongs to the technical field of feed processing, and discloses a compound bacterium enzyme additive for improving the quality of corn green and yellow silage feed and application, the additive comprises a core functional group and an optional functional group; the core functional group consists of xylanase and lactobacillus plantarum, the activity of the xylanase is 100000Ug, and the addition amount of the xylanase is 0.25 g / kg; the activity of the lactobacillus plantarum is 1 * 10 CFUg, and the addition amount is 1mL / kg; the optional functional group is cellulase, the activity of the cellulase is 20000Ug, the addition amount of the cellulase is 0.1 g / kg, and the optional functional group is used for reducing malathion residues in the silage corn. The green / yellow silage treated by the method has the fragrance of aromatic wine, the stem and leaf structure is well kept, the color is consistent with that of raw materials, and the sensory score reaches 20 (superior grade) which is far superior to the medium grade of a control group.

The application provides a xylanase mutant and application thereof. The xylanase mutant comprises: (a) a protein which is mutated based on a wild-type xylanase comprising an amino acid sequence shown in SEQ ID NO: 1, and the mutation site comprises any one or more of the following: T256, G67, H137, V173, R180, Y196, L248, I124, F170, A188 or S271; (b) a protein which has more than 70% homology with the amino acid sequence of the protein defined in (a) and has xylanase activity. The xylanase mutant can solve the problem of poor heat resistance of xylanase in the prior art and is suitable for the field of xylanase modification.

A method of producing a polyphenol-containing composition derived from herbaceous biomass includes: (1) bringing the herbaceous biomass into contact with an alkaline aqueous solution to obtain an extract; (2) adjusting pH of the extract obtained in step (1) to 3.2 or more and 4.5 or less and reacting the extract with an enzyme having cellobiohydrolase activity and xylanase activity to obtain an enzyme reaction solution; and (3) subjecting the enzyme reaction solution obtained in step (2) to solid-liquid separation to obtain a clear liquid containing a polyphenol-containing composition.

The present disclosure relates to a modified polypeptide having xylanase activity and the use thereof.

The invention discloses xylanase and application thereof, and belongs to the technical field of biology. The xylanase is named as RuXynJ, and the amino acid sequence of the xylanase is as shown in SEQ ID NO. 1. The novel xylanase RuXynJ is developed on the basis of a rumen microbial metagenome resource mining technology, has xylanase activity, can be used for degrading agricultural wastes, reducing the treatment cost and improving the degradation efficiency, is beneficial to improving the utilization rate and economic benefits of the agricultural wastes, and has a wide application prospect. And a basic support is provided for efficient resource utilization of agricultural wastes.

This invention discloses the application of glycine / glutamine enriched sequences in enhancing xylanase activity. The application of the glycine / glutamine enriched sequence shown in SEQ ID NO.1 in enhancing the xylanase activity of BCG1 and its homologous proteins is described. The xylanase activity of the originating BCG1 protein is enhanced by incorporating the glycine / glutamine enriched sequence shown in SEQ ID NO.1 into the C-terminus of a BCG1 protein lacking the glycine / glutamine enriched sequence; or the xylanase activity of the BCG1 protein is reduced by knocking out the glycine / glutamine enriched sequence of a BCG1 protein with xylanase activity. This finding indicates that glycine / glutamine enriched sequences have significant application potential in agricultural production for enhancing xylanase activity.

The invention concerns a thermostable protein expressing at least one xylanase activity, characterized in that it comprises or consists of a peptide sequence represented by SEQ ID NO: 1 including at least the L34C and R38C mutations, a polynucleotide encoding for such a protein, a vector allowing the expression of this polynucleotide in a host cell, a so-called host cell, as well as any application in particular in animal nutrition of said protein.

The application discloses a kind of xylanase activity enhanced mutant optimized by gating adjacent residues and application thereof.The application takes GH11 family xylanase XynLC9 derived from Bacillus subtilis as research object, carries out modeling to its structure using AlphaFold 3, carries out site-directed saturation mutation and combination mutation to candidate site by combining gating region adjacent residue analysis, and obtains xylanase mutant with enhanced activity.The mutant is mutated at the 123th and / or 124th position of the amino acid sequence shown in SEQ ID NO:1, preferably D123G and / or R124E, more preferably double mutant D123G / R124E.Compared with wild type, the relative enzyme activity of double mutant D123G / R124E is increased by 4.0 times, and it can be used for xylan degradation and xylo-oligosaccharide preparation.

The invention provides a xylanase mutant and application thereof. The xylanase mutant comprises (a) a protein mutated on the basis of wild type xylanase containing an amino acid sequence as shown in SEQ ID NO: 1, wherein mutated sites comprise any one or more of the following sites: T256, G67, H137, V173, R180, Y196, L248, I124, F170, A188 or S271; (b) protein which has 70% or more homology with the amino acid sequence of the protein limited in (a) and has xylanase activity. The method can solve the problem of poor heat resistance of xylanase in the prior art, and is suitable for the field of xylanase modification.