100 results about "High specific activity" patented technology

The invention discloses a collagenase mutant, a gene segment, a recombinant plasmid, a recombinant expression system, a collagen peptide, and a preparation method and application thereof, and belongs to the field of gene engineering and fermentation engineering. The collagenase mutant KT513 with high specific activity is obtained through recombinant expression in a trichoderma reesei host, and the enzyme activity of the collagenase mutant KT513 reaches 7423.18 U / mL. The optimum action pH of the enzyme is 3.0, the red snapper scale collagen can be subjected to enzymolysis in the pH range of 3.0-5.0, and the enzyme has excellent enzymolysis activity. After the collagenase mutant KT513 is subjected to enzymolysis at 40 DEG C for 4 hours, the extraction rate of fish scale collagen reaches 80.09%, and the prepared collagen peptide has good antioxidant activity. When the addition concentration is 10 mg / mL, the in-vitro scavenging activity of the prepared collagen peptide on hydroxyl radicals reaches 99.26% and is equivalent to that of ascorbic acid, and the collagen peptide has a wide application prospect in preparation of antioxidant preparations.

The invention discloses an all-potent nuclease mutant and application thereof, and relates to the technical field of biology. The invention provides an all-potent nuclease mutant. Compared with wild type all-potent nuclease as shown in SEQ ID NO: 1, the all-potent nuclease mutant comprises mutations at the following two positions: S22 and S115. The all-purpose nuclease mutant disclosed by the invention still has relatively high specific activity in a high-salt environment, and has a wide application prospect in preparation of medium-salt all-purpose nuclease products with high specific activity and good stability.

The invention provides an endoglucanase mutant and application of the endoglucanase mutant. The endoglucanase mutant comprises: 1) a protein which has at least one of the following sites in SEQ ID NO: 29: D194, T232 or G247, has a mutated amino acid sequence, and has endoglucanase activity; or 2) a protein which has an amino acid sequence with homology of at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% or at least 99% with the protein in 1) and has endoglucanase activity. Compared with a wild type, the endoglucanase mutant has higher specific activity and is beneficial to wide application of beta-endoglucanase in industry.

The invention relates to the technical field of agricultural biology, in particular to a high-activity multi-copper oxidase mutant V286N and application thereof in mycotoxin degradation. The amino acid sequence of the multi-copper oxidase mutant is as shown in SEQ ID NO: 2. The multi-copper oxidase mutant provided by the invention has higher specific activity. Compared with wild type multi-copper oxidase, the multi-copper oxidase mutant MCO-V286N provided by the invention has the advantages that the specific activity is improved by 0.8 time, the degradation efficiency on mycotoxin zearalenone is improved by 0.4 time, the production and application cost is effectively reduced, and the multi-copper oxidase mutant MCO-V286N has important application value and technical significance in wide application of the multi-copper oxidase in the field of mycotoxin detoxification of food and feed.

Compositions comprising high levels of high specific activity copper-64, and process for preparing said compositions. The compositions comprise from about 2 Ci to about 15 Ci of copper-64 and have specific activities up to about 3800 mCi copper-64 per microgram of copper. The processes for preparing said compositions comprise bombarding a nickel-64 target with a low energy, high current proton beam, and purifying the copper-64 from other metals by a process comprising ion exchange chromatography or a process comprising a combination of extraction chromatography and ion exchange chromatography.

The invention belongs to the technical field of biology, and discloses a UDP-glucosyltransferase mutant and an application thereof, and a preparation method of stevioside rebaudioside D. The UDP-glucosyltransferase mutant comprises a UDP-glucosyltransferase mutant, compared with the original UDP-glucosyltransferase comprising an amino acid fragment with the sequence shown as SEQ ID NO: 1, the UDP-glucosyltransferase mutant provided by the invention comprises H18P mutation and / or R370H mutation, and the mutation endows the UDP-glucosyltransferase mutant with higher specific activity for catalyzing the conversion of rebaudioside A into rebaudioside D, so that the UDP-glucosyltransferase mutant can be used for catalyzing the conversion of rebaudioside A into rebaudioside D; the high-efficiency and sufficient conversion from the rebaudioside A to the rebaudioside D can be realized, the realization of large-scale and high-efficiency production of the rebaudioside D is facilitated, and the method has a good application prospect.

The invention discloses a persistent endo-cellulase mutant with high specific activity and thermal stability and application of the persistent endo-cellulase mutant. A series of persistent endo-cellulase mutants are obtained by taking persistent endo-cellulase EG5C-1 derived from Bacillus subtilis as a template and combining mutation sites with deep learning prediction and a greedy algorithm, and compared with a wild enzyme, the optimal mutant M8 has the advantages that the activity of a substrate CMC (Carboxymethyl Cellulose) is improved by seven times, and the activity of a substrate Avicel is improved by four times. The content of reducing sugar generated by degrading filter paper by the continuous endo-cellulase mutant is greatly increased, and the continuous endo-cellulase mutant has important significance on efficient degradation of a cellulose substrate and reduction of the production cost.

The invention discloses an enterobacter hoffman JZ-3 strain and application thereof, and belongs to the technical field of microorganisms. The invention relates to an enterobacter hoffman strain JZ-3 with the preservation number of CGMCC No.33993. The degradation rate of the wool is 88.754%, and the degradation rate of the chicken feather is 34.222%. The specific activity is 127.420 U / mg when the pH value is 7 and the temperature is 30 DEG C. The invention also relates to application of the keratin degrading agent in preparation of keratin degrading products. Compared with the prior art, the invention has the following advantages: a plurality of bacteria are separated from intestinal tracts of costustotria moschata taking wool as food, a keratin culture medium is used for culturing to obtain bacterial strains with different wool keratin degradation capacities, the enterobacter hoffman JZ-3 which is inconsistent with that reported in literatures is found for the first time, the keratin bacterial strain of the bacterial strain has the highest specific activity, and the keratin bacterial strain has the highest specific activity. The degradation rate of the wool is 88.754%, and the wool degradation agent has good development value.

The invention belongs to the technical field of genetic engineering and protein engineering modification, and particularly relates to a high-specific-activity cellulase mutant and application thereof. Compared with wild cellulase, the specific activity of the mutant is improved by 51.9% and reaches 319 U / mg, and an unexpected technical effect is achieved. The mutant can be widely applied to the field of textile industry, is uniform in flower formation, small in flower point and strong in stereoscopic impression, most importantly, the strength loss of the fabric is very small, the strength retention rate is improved by 10-15% compared with that of the fabric treated by wild type cellulase, the use amount of the cellulase can be greatly reduced, the cost is reduced, and the application prospect is wide.

The invention relates to a self-cutting-resistant and high-specific-activity chymotrypsin mutant, in particular to a self-cutting-resistant and high-specific-activity chymotrypsin mutant obtained through molecular modification and screening and a coding gene and application of the self-cutting-resistant and high-specific-activity chymotrypsin mutant, and belongs to the technical field of protein and gene engineering. The chymotrypsin mutant provided by the invention is obtained by mutation of at least one of the following sites on the basis of an amino acid sequence as shown in SEQ ID NO.1: L97A, L162I, F71I, L83I, F114I and W207H. Compared with original chymotrypsin, the chymotrypsin has better self-cutting resistance and higher specific activity, compared with wild type chymotrypsin, the self-cutting resistance is improved by 82% at most, the specific enzyme activity is improved by 37% at most, and the problem that the activity is easily reduced due to self-cutting in the storage and use process of the chymotrypsin is solved.

Provided are high-specific-activity cellulase mutants and use thereof. Compared to the wild-type cellulase, the specific activity of the provided mutants that comprise single mutation sites P14A, P19T, S75A, S109N, H118P, M123I, M123L, I130L, I130Q, Y167E, Y167F, Y167W, A176S, A176F, D177S, and L192I, respectively, under neutral conditions is generally increased by 10.4% to 76.1%. The single-point mutant comprising I130L has the highest specific activity, which reaches 183.64 U / mg. The production costs of the cellulase mutants are significantly lower, which facilitates the wide use thereof.

Compositions comprising high levels of high specific activity copper-64, and process for preparing said compositions. The compositions comprise from about 2 Ci to about 15 Ci of copper-64 and have specific activities up to about 3800 mCi copper-64 per microgram of copper. The processes for preparing said compositions comprise bombarding a nickel-64 target with a low energy, high current proton beam, and purifying the copper-64 from other metals by a process comprising ion exchange chromatography or a process comprising a combination of extraction chromatography and ion exchange chromatography.

Compositions comprising high levels of high specific activity copper-64, and process for preparing said compositions. The compositions comprise from about 2 Ci to about 15 Ci of copper-64 and have specific activities up to about 3800 mCi copper-64 per microgram of copper. The processes for preparing said compositions comprise bombarding a nickel-64 target with a low energy, high current proton beam, and purifying the copper-64 from other metals by a process comprising ion exchange chromatography or a process comprising a combination of extraction chromatography and ion exchange chromatography.

The present invention relates to the technical fields of genetic engineering and protein engineering modification, and particularly relates to a high-specific-activity alginate lyase mutant. The specific activity of the alginate lyase mutant is significantly higher than that of the wild type, and it can be widely used in the field of seaweed processing, effectively improving the enzymatic hydrolysis efficiency of seaweeds such as Sargassum and Ascophyllum nodosum, and having broad market prospects.

The application discloses a kind of high specific activity alpha-galactosidase mutant and application thereof.The alpha-galactosidase AgaV derived from Anoxybacillus vitaminiphilus is used as template, amino acid mutation is carried out by using molecular biology technology, a kind of mutant with improved catalytic efficiency is obtained, including A55N, G530C, P579Y and N580Q.The mutant has high catalytic efficiency, and the efficiency of catalyzing synthesis of ectocarpin with D-galactose and glycerol as substrates is improved by 1.5-2.0 times, which is beneficial to reduce the cost of ectocarpin synthesis, improve the conversion efficiency of using the enzyme to produce ectocarpin, and has wide application prospect.

Compositions comprising high levels of high specific activity copper-64, and process for preparing said compositions. The compositions comprise from about 2 Ci to about 15 Ci of copper-64 and have specific activities up to about 3800 mCi copper-64 per microgram of copper. The processes for preparing said compositions comprise bombarding a nickel-64 target with a low energy, high current proton beam, and purifying the copper-64 from other metals by a process comprising ion exchange chromatography or a process comprising a combination of extraction chromatography and ion exchange chromatography.

The present application relates to the technical field of genetic engineering and protein modification, and particularly relates to a cellulase mutant with improved specific activity and application thereof. The cellulase mutant has higher specific activity under the condition of 50 DEG C. Compared with the wild type, the specific activity of the cellulase mutant provided by the present application, which respectively contains N60Q, L78V, A92E, N124Q, M125I, Q169E, Q187R, S230G, D239A single-point mutations, is generally increased by 8.6%-35.7% under the condition of 50 DEG C. Among them, the specific activity of the L78V single-point mutant and the N124Q single-point mutant is increased by 30% and 35.7% respectively, thereby facilitating the wide application of the cellulase in the textile field.

The invention relates to the technical field of genetic engineering and protein engineering modification, in particular to a high-specific-activity alkaline protease mutant. According to the invention, on the basis of wild type alkaline protease AprE from bacillus clausii, a mutant containing mutation sites selected from the group consisting of V30I, I77L, I77V, S101G, N138Q, N138K, F183D, V197I, V197L, P219W, P219E, A226G and A226T is provided. The specific activity of the mutant is remarkably improved, the production cost of the enzyme is reduced, and wide application of the enzyme in the field of washing industry is promoted.

The present application relates to the field of agricultural biotechnology, and in particular to a high-activity multicopper oxidase mutant V286N and its application in mycotoxin degradation. The amino acid sequence of the multicopper oxidase mutant is shown as SEQ ID NO: 2. The multicopper oxidase mutant provided by the present application has higher specific activity. Compared with the wild-type multicopper oxidase, the specific activity of the multicopper oxidase mutant MCO-V286N provided by the present application is increased by 0.8 times, the degradation efficiency of mycotoxin zearalenone is increased by 0.4 times, the production and application cost is effectively reduced, and the multicopper oxidase has important application value and technical significance for the wide application of the multicopper oxidase in the field of mycotoxin detoxification of food and feed.

The invention relates to the technical field of genetic engineering and protein engineering modification, in particular to a high-specific-activity alkaline protease mutant. According to the invention, on the basis of wild type alkaline protease AprE from bacillus clausii, a mutant containing mutation sites selected from the group consisting of V30I, I77L, I77V, S101G, N138Q, N138K, F183D, V197I, V197L, P219W, P219E, A226G and A226T is provided. The specific activity of the mutant is remarkably improved, the production cost of the enzyme is reduced, and wide application of the enzyme in the field of washing industry is promoted.

The present invention relates to the technical fields of genetic engineering and protein engineering modification, and particularly relates to a high-specific-activity alginate lyase mutant and its application. The alginate lyase mutant provided by the present invention has a significantly higher specific activity than the wild-type alginate lyase under the low-temperature condition of 40°C, achieving an unexpected technical effect. It can be widely used in the field of seaweed processing, effectively improving the enzymatic hydrolysis efficiency of seaweeds such as Sargassum and Ascophyllum nodosum, and having a broad market prospect.

The invention belongs to the technical field of gene engineering, and discloses a xylanase mutant as well as a preparation method and application thereof. Compared with parent xylanase with an amino acid sequence as shown in SEQ ID NO: 1, the xylanase mutant has sequence identity of not less than 99%; and the compound contains at least one of the following substitutions: N24S, D113G and E251G. Compared with parent xylanase, the xylanase mutant provided by the invention has higher specific activity, has higher relative enzyme activity at the optimal reaction temperature and reaction pH, and is beneficial to industrial application.

The present application relates to the technical field of genetic engineering and protein modification, and particularly relates to a high specific activity cellulase mutant and application thereof. The mutant provided by the present application comprises substitution of amino acids at at least one position selected from the group consisting of 44, 84, 109, 123, 178, 183, 194, 225 and 234. The specific activity of the mutant at 50 DEG C is generally increased by 7.1% to 38%; wherein the specific activity of the S44N single-point mutant, the I123L single-point mutant and the L194I single-point mutant is respectively increased by 26.8%, 25.7% and 38%, thereby facilitating the wide application of the cellulase in the textile field.

The present application relates to the technical field of genetic engineering and protein modification, and particularly relates to a high specific activity cellulase mutant and application thereof. The mutant provided by the present application comprises substitution of amino acids at at least one position selected from the group consisting of 44, 84, 109, 123, 178, 183, 194, 225 and 234. The specific activity of the mutant at 50 DEG C is generally increased by 7.1% to 38%; wherein the specific activity of the S44N single-point mutant, the I123L single-point mutant and the L194I single-point mutant is respectively increased by 26.8%, 25.7% and 38%, thereby facilitating the wide application of the cellulase in the textile field.

The present disclosure is directed compositions and formulations comprising high levels of high specific activity copper-64, and process for preparing said compositions. The compositions comprise from about 2 Ci or greater of copper-64 and have specific activities up to about 3850 mCi copper-64 per microgram of copper. The processes for preparing said compositions comprise bombarding a nickel-64 target with a low energy, high current proton beam, and purifying the copper-64 from other metals by a process comprising ion exchange chromatography or a process comprising a combination of extraction chromatography and ion exchange chromatography.

The invention discloses an alginate lyase VxAly7B-CM mutant obtained through directed evolution of a T7 biosensor as well as a directed evolution method and application of the alginate lyase VxAly7B-CM mutant. The nucleotide sequence of a mutant 1 of the alginate lyase VxAly7B-CM provided by the invention is as shown in SEQ ID No.3, the amino acid sequence of the mutant 1 is as shown in SEQ ID No.4, the nucleotide sequence of a mutant 2 is as shown in SEQ ID No.5, and the amino acid sequence of the mutant 2 is as shown in SEQ ID No.6. The high specific activity and high stability of the mutant provided by the invention exceed those of most reported alginate lyase. The algin lyase VxAly7B-CM mutants 1 and 2 keep a catalytic mode and degradation products consistent with those of a wild type VxAly7B-CM, the degradation mode is an incision type, and the degradation final products are mainly unsaturated disaccharide, trisaccharide, tetrasaccharide and pentasaccharide. The invention also constructs a recombinant vector and a recombinant strain containing the mutant, and the recombinant vector and the recombinant strain can be used for degrading seaweed or algin to prepare AOS in industrial production.

This application belongs to the field of genetic engineering technology and discloses human enterokinase light chain mutants and their applications. This application involves single-point mutations or multiple rounds of combined mutations based on the wild-type human enterokinase light chain -C112S mutant sequence. The obtained variants have higher specific activity compared to the parent, which is expected to increase unit yield, reduce the residual amount of protease in the final product, and lower product costs. Furthermore, these mutants exhibit high stability in the enzymatic digestion of peptides / proteases, such as liraglutide and smegglutide, GLP-1 analogs, reducing enzyme usage, increasing digestion efficiency, and decreasing the proportion of non-specific products, thereby lowering the production cost of peptide drugs and promoting the rapid development of related industries.

The invention belongs to the technical field of biology, and particularly relates to a carboxypeptidase B (CPB) precursor gene sequence, a recombinant carboxypeptidase B precursor and a preparation method of carboxypeptidase B. The gene sequence of the carboxypeptidase B precursor is as shown in SEQ ID No.6, the amino acid sequence of the carboxypeptidase B precursor is as shown in SEQ ID No.5, the gene sequence of the CPB enzyme target gene is as shown in SEQ ID No.2, and the amino acid sequence of the CPB enzyme target gene is as shown in SEQ ID No.4. The preparation method of the CPB comprises the following steps: (1) cloning and constructing a CPB enzyme expression vector; (2) expressing CPB precursor protein by using engineering bacteria to form an inclusion body; (3) thalli are washed, crushed and centrifuged, inclusion bodies are collected, and denatured dissolution is performed; (4) inclusion body renaturation; and (5) activating and purifying CPB. The process is simple and convenient in steps, does not use animal pancreas, and reduces the possibility of infection; the obtained CPB enzyme has high specific activity, and the yield of each liter of fermentation liquor is high, so that the method is suitable for large-scale production and application.

The present invention relates to the field of genetic engineering and protein modification technology, and proposes a high specific activity alpha-amylase mutant and its application. The present invention is based on wild-type alpha-amylase A1, and provides a mutant comprising at least one mutation site in N39T, P145N, D159Y, F191N, Q240S, D279N, R306S, T310N, H319T, and I477V. Compared with wild-type alpha-amylase A1, the specific activity of the xylanase mutant provided by the present invention is generally increased by 26.2%-35.7%; wherein, the specific activity of the alpha-amylase mutant containing the T310N single-point mutation is the highest, reaching 1251.38U / mg, which is conducive to reducing the production cost of the enzyme and promoting its wide application in the industrial field.

The present invention discloses a high specific activity raw starch hydrolase mutant, its encoding gene, an expression strain thereof and applications thereof. In the present invention, α-amylase Amy with poor stability is used as the starting enzyme, and through site-directed mutagenesis, a mutant Amy:ΔTG / W345A with improved thermal stability is obtained. When corn raw starch is used as the substrate, the specific enzyme activity of the mutant is 85% of that of the starting enzyme, and its thermal stability is greatly improved under the conditions of 30-35 °C. Under the conditions of 35 °C and pH 7.0, the half-life can reach 20 h. While the specific enzyme activity is close to that of the starting enzyme, the thermal stability is greatly improved. This mutant has potential application value in the field of sugar-making industry using corn raw starch as the substrate.