53results about How to "High specific vitality" patented technology

The invention discloses a new nitrilase and gene thereof, a recombinant expression vector and a recombinant expression transformant containing the gene, a method for preparing the recombinant nitrilase or microbial cell containing the recombinant nitrilase by use of the recombinant expression transformant, and application of the microbial cell in dehydrating ortho-chlorine mandelonitrile or other analogues and producing chiral ortho-chlorine mandelonitrile or other analogues. The recombinant nitrilase disclosed by the invention comes from Labrenzia aggregate and can be used as a catalyst for dehydrating and splitting ortho-chlorine mandelonitrile or other analogues; and the recombinant nitrilase has the advantages of high catalysis efficiency, strong enantioselectivity, mild reaction conditions, environmental friendliness and the like.

The present invention is Agkistrodon acutus venon 36KD single-stranded hemocoagulase and its preparation process, and aims at providing single-stranded Agkistrodon acutus venon hemocoagulase with high potency and low toxicity. SDS-PAGE electrophoresis shows that the hemocoagulase has molecular weight of 36KD+/-2KD, single color zone, and at least 90 % homogeneity with the N end sequence of the single-stranded amino acid shown in SEQ ID No. 1. The preparation process includes dissolving Agkistrodon acutus venon in Tris-HCl buffering solution (pH8.0) and dialysis; adding the supernatant to Metal Sepharose F.F affinity chromatographic column and collecting the penetrating peak component; adding the penetrating peak component to DEAE-Sepharose F.F ion exchange column and collecting active peak component; separating in Superdex 75 column and Sephacryl S-100 column; desalting in Sephadex G-25 column; sterilizing and freeze drying.

The invention belongs to the technical field of enzyme engineering, and relates to a S-adenosyl-L-methionine synzyme mutant and a preparation method using the same. The mutant is mutated into a plurality of amino acid sites in wild S-adenosyl-L-methionine synzyme of which the amino acid sequence is shown as SEQID NO.1, and the mutated amino acid sites comprise C9R and K224R. According to the S-adenosyl-L-methionine synzyme mutant and the preparation method using the same, compared with the wild S-adenosyl-L-methionine synzyme, the mutant has higher specific activity and has higher product yield and lower enzyme activity reduction when catalyzing is performed for preparing the S-adenosyl-L-methionine synzyme.

The invention discloses externally tangent type algin lyase VsAly7D and a recombinant strain and application thereof. The amino acid sequence of the externally tangent type algin lyase disclosed by the invention is as shown in SEQ ID No.6, and the nucleotide sequence of the coding amino acid sequence is as shown in SEQ ID No.5. The suitable reaction temperature of the externally tangent type alginlyase is 20-35 DEG C, and the externally tangent type algin lyase has high stability at 0-30 DEG C, so that the enzyme can effectively degrade substrate at low temperature and belongs to cold-adaptedalgin lyase; the externally tangent type algin lyase has degradation capacity on algin, polyG and polyM, a degradation manner is an externally tangent type, and a final degraded product is unsaturated monose and has NaCl dependence. The invention further constructs a recombinant carrier and recombinant strain containing externally tangent type algin lyase VsAly7D coded genes, and a favorable basecan be provided for industrialized application and production of biologic ethanol.

The invention discloses low-immunogenicity lumbrukinase, a preparation method and application thereof, and belongs to the field of biological pharmacy. The method provided by the invention comprises the following steps of: first, extracting to obtain a lumbrukinase crude product from an earthworm, and then, passing the crude product through an ion exchange column to elute, purifying, colleting a component with fibrinolytic activity, freezing, drying, concentrating, separating a concentrated lumbrukinase solution by using a gel filtration chromatographic column, detecting the fibrinolytic activity by using an agarose-hemaleucin flat band method, collecting a second eluting peak with the fibrinolytic activity, wherein detected by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electropheresis), the molecular weight of the second eluting peak is 23500-27500 Da; and after the eluting peak is dialyzed, desalted and subjected to low-temperature freeze drying, carrying out molecular modification on the eluting peak by utilizing activated monomethoxy polyethyleneglycol and dextran to obtain the low-immunogenicity lumbrukinase. The lumbrukinase prepared by the invention has the characteristics of low immunogenicity, high enzyme activity and the like, and can be used for the research and the preparation of an antithrombotic drug and a drug for treating or preventing cardiovascular and cerebrovascular diseases.

The invention belongs to the technical field of enzyme engineering, and relates to a tyrosinase mutant and application thereof. According to the tyrosinase mutant, a plurality of amino acid sites are mutated in wild type tyrosinase with an amino acid sequence as shown in SEQ ID NO.1. According to the tyrosinase mutant and the method for preparing theaflavin by using the tyrosinase mutant, the mutant has higher specific activity than wild type tyrosinase, and has higher yield during catalytic preparation of theaflavin.

The invention discloses efficient xyloglucanase and application thereof, and the efficient xyloglucanase is derived from Coniella vitis and is selected from one of the following: (a) a protein with the 19-390 amino acid sequence in SEQ ID NO: 3, (b) a protein with an amino acid complete sequence as shown in SEQ ID NO: 3; and (c) a protein which has the complete sequence as shown in SEQ ID NO: 3 or the 19-390th amino acid sequence which is subjected to conservative substitution, deletion or insertion by one or more amino acids and has the same function as the complete sequence as shown in SEQ ID NO: 3. The invention also provides a coding gene of the high-efficiency xyloglucanase, a recombinant expression vector containing the gene, an engineering bacterium and application thereof. The efficient xyloglucanase has excellent endo-xyloglucanase activity, the enzyme activity is kept stable under a strong acid condition, the characteristic completely meets the condition requirements of a synchronous saccharification and fermentation process, and the efficient xyloglucanase has a very high application prospect in many fields as the endo-xyloglucanase.

The invention specifically provides a GDP-mannose-4,6-dehydratase-encoding gene in Sacchrina japonica, and a protein and application thereof, belonging to the field of genetic engineering technology. The gene is derived from Sacchrina japonica and is named gene SjaGM46D1. The nucleotide sequence of the gene is a sequence shown as SEQ ID NO. 1. An amino acid sequence of the gene encoding the protein is a sequence as shown in SEQ ID NO. 2, and the protein is GDP-mannose-4,6-dehydratase. According to the invention, the gene sequence is cloned by using gene cloning technology, and a prokaryotic expression vector is constructed. The results of enzyme activity assay of the recombinant protein show that the recombinant protein is capable of catalyzing the conversion of GDP-mannose into GDP-4-keto-6-deoxymanose, can be applied to the synthesis of GDP fucose, and has significantly higher activity compared with other GDP-mannose-4,6-dehydratases disclosed in the prior art.