333 results about "Isoleucine" patented technology

The invention provides a fluorescent protein selection marker staygold-ynaMr gene and application thereof, and belongs to the technical field of biological engineering. The method comprises the following steps: replacing codons of L-isoleucine in nucleotide sequences of a fluorescent protein gene staygold and a gene ynaM by using a rare codon ATA to respectively obtain the fluorescent protein gene staygold after codon replacement and the gene ynaMr after codon replacement, and connecting the two segments of genes after codon replacement by using a flexible protein peptide, and the fluorescent protein selection marker staygold-ynaMr gene is obtained. Experiments prove that the gene can obviously improve the screening efficiency of L-isoleucine high-yield strains.

The invention relates to the technical field of functional product preparation, and provides a rhizoma polygonati and saussurea involucrata bone marrow peptide tablet as well as a preparation method and application thereof. The rhizoma polygonati and saussurea involucrata bone marrow peptide tablet is prepared from the following components: collagen peptide powder, L-isoleucine, a compound nutrient supplement, rhizoma polygonati, sorbitol, yak bone marrow peptide powder, fructus phyllanthi, fructus alpiniae oxyphyllae, mulberry powder, a saussurea involucrata culture and magnesium stearate. All the components of the rhizoma polygonati and saussurea involucrata bone marrow peptide tablet disclosed by the invention have a synergistic effect, so that the effects of conditioning sub-health, maintaining joints and assisting in treating diseases can be achieved.

The invention belongs to the technical field of genetic engineering and enzyme engineering, and particularly relates to a genetically engineered bacterium for stably and efficiently producing L-isoleucine as well as a construction method and application of the genetically engineered bacterium. The genetically engineered bacterium takes E. coliTHRD as a host and contains an RNA (Ribonucleic Acid) polymerase beta-subunit mutant coding gene rpoBM; compared with a parent RNA polymerase beta-subunit, the RNA polymerase beta-subunit mutant has the advantage that the amino acid residue at the 618th site of the amino acid sequence is sequentially replaced with leucine from the N terminal to the C terminal. The genetically engineered bacterium disclosed by the invention can tolerate L-isoleucine and accumulate less alpha-ketobutyric acid, and has a very good industrial application prospect.

The invention provides a nicotinamide nucleotide transhydrogenase mutant and application thereof, valine at the 169th site of the nicotinamide nucleotide transhydrogenase mutant is designed to be mutated into isoleucine, the isoleucine is used for constructing a lysine production strain, and the new strain does not contain plasmids, does not have growth defects, does not need induction, and has the advantages of good genetic stability, high fermentation yield and the like. The lysine can be efficiently and stably produced from the beginning by taking glucose as a substrate.

The invention discloses a method for inhibiting production of vomitoxin from bacillus cereus, which is characterized in that isoleucine is added into a substance needing to inhibit production of vomitoxin from bacillus cereus, preferably 5-20mM of isoleucine is added. According to the present invention, the content of the toxin is detected through the liquid chromatography-mass spectrometry, and the cytotoxicity experiment verification results show that the isoleucine can significantly inhibit the synthesis of the vomitoxin of the bacillus cereus in the culture medium and the matrix, and can effectively reduce the toxic effect of the toxin on HeLa cells; the invention provides a safe and efficient biological control means which is suitable for various food systems such as starch food, dairy products, meat products and the like. Isoleucine can be used as a novel non-toxic and harmless food additive and is low in cost; the use method is simple, the output of vomitoxin can be reduced by directly adding a trace amount of isoleucine, and the food flavor is not affected.

The invention discloses a high-stability carbonyl reductase mutant and application of the high-stability carbonyl reductase mutant in chiral alcohol synthesis. An amino acid sequence as shown in SEQ ID NO.2 is mutated as follows: 20th leucine is replaced by any one of lysine, threonine, aspartic acid or isoleucine, and / or 55th leucine is replaced by any one of methionine, serine, lysine or isoleucine, and / or 55th leucine is replaced by any one of methionine, serine, lysine or isoleucine. Compared with a wild type enzyme, the stability of the obtained mutant is remarkably improved, particularly, single-point mutants Mut-L20I and Mut-L55I and a combined mutant Mut-L20I-L55I show excellent relative enzyme activity, thermal stability and substrate tolerance. The mutant has high catalytic activity and stability to various chiral alcohols, has the advantages of high catalytic efficiency, high thermal stability, strong substrate tolerance, easiness in fermentation production and the like, and is suitable for industrial application of enzymatic synthesis of chiral alcohols.

The present application relates to a pyridoxal kinase mutant, a recombinant expression vector and a microbial cell and their applications, and belongs to the technical field of biological catalysis. In order to solve the problem of low product concentration in existing enzyme catalysis, a pyridoxal kinase mutant is provided, the amino acid sequence is selected from the amino acid sequence shown in SEQ ID NO. 1, the lysine at position 229 is mutated to alanine, phenylalanine, methionine, arginine, threonine, histidine, serine, tyrosine, valine, leucine, isoleucine, proline, asparagine, aspartic acid or glutamic acid; the pyridoxal kinase mutant is used for catalyzing pyridoxal to synthesize pyridoxal phosphate, and a recombinant expression vector and a microbial cell can be further formed. The present application has good enzyme activity, high product conversion rate, high concentration of pyridoxal phosphate obtained, and the concentration of the product catalyzed by the wild-type pyridoxal kinase to phosphorylate pyridoxal is obviously improved.

The invention provides an SNP (Single Nucleotide Polymorphism) marker for targeted identification of systemic lupus erythematosus of children and application of the SNP marker. A new SNP site (RS25671007) is identified in a child systemic lupus erythematosus patient through whole exon sequencing, the site is located at the 734th pair of basic groups of a PABPC3 gene, and mutation from C to T exists at the site, or mutation from threonine to isoleucine exists in coded amino acid. In addition, in-vitro cell model experiments prove that the SNP causes significant up-regulation of the antibody type transformation function, and the SNP can be used as a reference marker for risk stratification or medication guidance of early targeted diagnosis, detection, gene evaluation and the like of systemic lupus erythematosus of children.

The present invention relates to the fields of agriculture, plant biotechnology, and molecular biology. Specifically, the present invention relates to a wheat EPSPS mutant protein and use thereof in improving the tolerance of wheat to glyphosate. The mutant protein comprises an amino acid sequence having the following mutations compared to the EPSPS amino acid sequence of any genome of wild-type wheat: in the amino acid sequence set forth in SEQ ID NO: 2, the amino acid at position 168 is mutated from threonine to isoleucine, the amino acid at position 169 is mutated from alanine to valine, and the amino acid at position 172 is mutated from proline to serine. The mutant protein enables the production of stable glyphosate-resistant wheat, showing important significance for wheat breeding.

The invention relates to aspartate kinase for relieving feedback inhibition of L-threonine and application of aspartate kinase, and belongs to the field of enzyme engineering and metabolic engineering. The mutant is obtained by carrying out E253K and / or K507E mutation on the basis of wild type aspartate kinase as shown in SEQ ID NO.1, the enzyme activity of the mutant is not obviously changed under the condition that the concentration of L-threonine is 0-12 mmol / L, and the feedback inhibition effect of L-threonine on the mutant is relieved. The method can be widely applied to synthesis of essential amino acids including L-threonine, L-tryptophan, L-isoleucine, L-lysine, L-leucine, L-valine, L-methionine, L-phenylalanine and the like.

The invention belongs to the technical field of biology, and discloses a transaminase GabT1 mutant S106I, a construction method thereof and application of the transaminase GabT1 mutant S106I in biosynthesis of 1-deoxynojirimycin. According to the invention, the 106th serine near the molecular catalytic domain of the transaminase GabT1 derived from bacillus amyloliquefaciens is mutated into isoleucine in a site-directed mutagenesis manner, so that the catalytic efficiency of the transaminase GabT1 is remarkably improved, the problem that the catalytic efficiency of the transaminase GabT1 on fructose-6-phosphoric acid is not high at present is solved, and the application of the transaminase GabT1 to the fructose-6-phosphoric acid is promoted. The yield of 1-deoxynojirimycin synthesized by the mutant GabTS106I is increased by 43.87% compared with that of a wild type. The 1-deoxynojirimycin fermentation production capability of the transaminase GabT1 mutant and the engineering strain obtained by the invention is greatly improved, and the transaminase GabT1 mutant and the engineering strain have a good industrial application prospect.

An Fc-binding polypeptide with improved alkaline stability comprising a mutant of the Fc-binding domain of Staphylococcus protein A (SpA), said mutant being defined by SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 22, SEQ ID NO 51 or EQ ID NO 52, wherein at least the asparagine or serine residue at a position corresponding to position 11 in SEQ ID NO: 4-7 has been mutated to an amino acid selected from the group consisting of glutamic acid, lysine, tyrosine, threonine, phenylalanine, leucine, isoleucine, tryptophan, methionine, valine, alanine, histidine and arginine.

The present invention addresses the problem of providing a composition for lyophilizing extracellular vesicles or artificial cell vesicles, which makes it possible to prevent the extracellular vesicles or the artificial cell vesicles from being deteriorated in shape preserving properties or functions thereof or from being reduced in particle diameters when the extracellular vesicles or the artificial cell vesicles are recovered by hydration after lyophilization. The composition for lyophilizing extracellular vesicles or artificial cell vesicles is prepared, the composition being characterized by being intended to be added to extracellular vesicles or artificial cell vesicles upon use and also being characterized by containing the following hydrophobic substances: (a) phenylalanine or a methyl ester thereof; (b) a dipeptide which is composed of one or two kinds of hydrophobic amino acids selected from the group consisting of phenylalanine, leucine, glycine, valine, isoleucine, tryptophan, and alanine and contains at least one phenylalanine molecule as a constituent amino acid; and the like.

The application relates to the technical field of beef cattle breeding, and particularly discloses a compound preparation for promoting the feed intake, daily weight gain and improving the meat quality of beef cattle and application thereof, which is prepared from the following components in percentage by volume: 40% of micro-ecological preparation, 30% of hawthorn, 10% of medicated leaven, 10% of malt, 5% of areca nut and 5% of dried tangerine or orange peel; the compound preparation is prepared from microorganisms and multiple natural Chinese herbal medicines in a specific and scientific matching ratio; experiments prove that the compound preparation can increase the feed intake of beef cattle by 11.33%, increase the daily weight gain by 16.16%, and significantly shorten the breeding cycle; meanwhile, the contents of aspartic acid, threonine, glutamic acid, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine, lysine, arginine and proline in the muscle are significantly increased, the nutritional quality and flavor taste of beef are effectively improved, the preparation is natural, residue-free and side-effect-free, the preparation method is simple, the cost is low, and the preparation has extremely high practical value and popularization prospect.

This invention provides a ketolic acid reductase mutant and its application in constructing genetically engineered bacteria that produce high levels of D-pantothenic acid. To address the technical problem of low D-pantothenic acid yield in existing microbial fermentation, this invention utilizes semi-rational enzyme design to obtain a substrate-specific ketolic acid reductase mutant, which is then applied to construct genetically engineered bacteria that produce high levels of D-pantothenic acid. Furthermore, this invention employs CRISPR-Cas9 gene editing technology to construct genetically engineered bacteria that produce high levels of D-pantothenic acid using the aforementioned ketolic acid reductase mutant, increasing D-pantothenic acid production by approximately 12.04%. Compared to the starting strain, the accumulation of valine in the fermentation broth remained almost unchanged compared to the control, but the accumulation of the branched-chain amino acid isoleucine was lower, achieving substrate-specific modification of the ketolic acid reductase.

The present application relates to a microorganism capable of producing L-isoleucine, into which a gene encoding an exogenous glutamate dehydrogenase has been introduced, a method for producing L-isoleucine using the microorganism, and a composition for producing L-isoleucine containing the microorganism.

The invention belongs to the field of in-vitro diagnostic reagents, and particularly relates to application of a reagent for detecting biomarkers in serum in preparation of a cerebral arterial thrombosis diagnostic kit. The invention determines that the concentrations of lactic acid, isoleucine, fumaric acid, ketoglutaric acid, hypoxanthine, tyrosine, histidine and inosine in serum of a cerebral arterial thrombosis (IS) patient are significantly related to major atherosclerosis (LAA) and minor artery occlusion (SAO), so that the concentrations of the biomarkers can be used as a basis for diagnosing IS and distinguishing LAA and SAO.

The present invention addresses the problem of providing a cocoa substitute that can be used as a cocoa-derived component substitute, and of providing a novel oily food having a good flavor even when a cocoa-derived component has been reduced. A cocoa substitute satisfying all of the following requirements (1) to (5): (1) containing at least one legumes as a starting material, (2) being a baked product containing a crushed legumes, (3) containing 0.5-3.8 mg / g of free amino acids in a fat-free solid content, and (4) containing the free amino acids in the fat-free solid content satisfying all of the following ratios. (4-1) the sum of isoleucine and leucine is 1-20% by mass (inclusive) in the free amino acids, (4-2) the sum of glutamine and glutamic acid is 3-30% by mass (inclusive) in the free amino acids, (4-3) lysine is 1.5-10% by mass (inclusive) in the free amino acids, and (5) the oil content is 3-30% by mass (inclusive).

The present disclosure can improve the degree of soy protein proteolysis and the ability to produce valine, isoleucine, and leucine, which are branched-chain amino acids, as well as other amino acids, such as threonine, glycine, tyrosine, and lysine. Accordingly, the present disclosure can prevent sarcopenia and has antioxidant activity. Also, the present disclosure can maintain protein metabolic balance and relieve sarcopenia by muscle synthesis.The self-aggregation, hydrophobicity, and intestinal adhesion of a mixed strain is improved compared to a case where a single strain used for the mixed strain is used. Therefore, when the mixed strain of the present disclosure is ingested, the strain can remain for a long time in the intestine.

The present invention relates to an antibody or binding fragment thereof that binds to a protein, preferably a T cell receptor, comprising an epitope comprising or consisting of an amino acid sequence having at least 80 %, such as 83 %, preferably at least 90 %, for instance 100 % sequence identity to the amino acid sequence set forth in SEQ ID NO: 62 (EVPKXiR), wherein Xi is selected from Alanine (A), Arginine (R), Asparagine (N), Aspartic acid (D), Cysteine (C), Glutamine (Q), Glutamic acid (E), Glycine (G), Histidine (H), Isoleucine (I), Leucine (L), Lysine (K), Methionine (M), Phenylalanine (F), Proline (P), Serine (S), Threonine (T), Tryptophan (W), Tyrosine (Y), Valine (V). Further, the invention relates to pharmaceutical compositions comprising such an antibody or binding fragment thereof and to the use of such an antibody or binding fragment thereof for use as a medicament or for use as a screening agent.

The present disclosure relates to a novel polynucleotide exhibiting promoter activity, and a method for producing L-isoleucine using same. A microorganism having the novel polynucleotide according to the present disclosure, in which specific positions of promoter regions of an NCgl0302 gene and / or an NCgl0123 gene are mutated, has significantly increased L-isoleucine productivity, and thus the novel polynucleotide can be effectively used to efficiently produce L-isoleucine.

A collagen-boosting supplement that contains at least 4, optionally at least 10, collagen building block amino acids and is substantially free of histidine. The building block amino acids may be selected from: Glycine, L-Proline, L-Hydroxyproline, L-Glutamic Acid, L-Alanine, L-Arginine, L-Aspartic Acid, L-Serine, L-Leucine, L-Lysine, L-Hydroxylysine, L-Valine, L-Phenylalanine, L-Threonine, L-Isoleucine, L-Methionine, and L-Tyrosine. The supplement may further comprise: vitamin C; one or more mast cell stabilisers which may be selected from: quercetin, molybdenum, bromelain, DAO (diamine oxidase), Urtica Dioica (stinging nettle), Nigella Sativa (black cumin), Zingiber (ginger), Scutellaria baicalensis (Chinese skullcap), Sambucus (Elderberry), Aloe Vera, Syzygium aromaticum (clove), and matcha; one or more collagen-strengthening herbs which may be selected from: Bilberry, Centella, and Astragulus; one or more Glucosaminoglycans (GAGs) which may be selected from: Hyaluronic acid, glucosamine, and chondroitin; one or more antioxidants which may be selected from: astaxanthin and resveratrol; and / or one or more cofactors which may be selected from: zinc, biotin, silicon, manganese, magnesium, Vitamin D, Vitamin A, Vitamin E, and iron. The supplement may be a foodstuff, medicament, nutraceutical, or cosmetic. The supplement may be used to treat hypermobile Ehlers-Danlos syndrome (hEDS) while reducing the likelihood of mast cell degranulation through histamine activation.

The application discloses a kind of genetic engineering escherichia coli plasmid expression culture medium and fermentation process, including basic medium and feed medium;The basic medium includes glycerol, yeast hydrolysate, yeast peptone, L-glutamic acid, L-valine, L-isoleucine, arginine, tyrosine, lysine, proline, glycine, ammonium sulfate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, citric acid, magnesium sulfate, ferrous sulfate, zinc sulfate, calcium chloride, manganese chloride, cobalt chloride, copper chloride, sodium ethylenediaminetetraacetate;Feed medium includes glycerol, citric acid, magnesium sulfate, ferrous sulfate, zinc sulfate, calcium chloride, manganese chloride, cobalt chloride, copper chloride, sodium ethylenediaminetetraacetate.The application inhibits the accumulation of harmful metabolites, and creates the optimal intracellular environment for stable replication of plasmid.In industrial fermentation scale, the amount of plasmid harvested per liter of fermentation broth is more than 1 gram, and the supercoiling ratio of plasmid DNA is stably maintained at more than 90%, with minimal batch-to-batch variation.

The invention discloses a pinene synthase mutant and application thereof in pinene production, and belongs to the technical field of bioengineering. Isoleucine at the 409th site of pinene synthase is mutated into valine, phenylalanine at the 443rd site of pinene synthase is mutated into alanine, overexpression is carried out in serratia marcescens (HBQA7), and an engineering strain ST17 is constructed. Under the condition of shake flask fermentation, the pinene yield of the engineering strain ST17 reaches 0.80 g / L; the yield is obviously increased to 43.2 g / L through amplification culture in a 30 L fermentation tank. The invention provides an efficient, economic and environment-friendly novel method for industrial biosynthesis of pinene.

The invention discloses a recombinant full-length human-derived III-type collagen as well as a preparation method and application of the recombinant full-length human-derived III-type collagen. The method comprises the following steps: replacing at least one corresponding rare codon of glycine, proline, arginine, leucine, isoleucine, valine and / or glutamic acid host bacteria in a Gly-Pro-X or Gly-X-Pro tripeptide structure coded by a wild full-length human III-type collagen gene sequence with a synonymous codon used by the host bacteria at high frequency; the translation efficiency in prokaryotic systems such as escherichia coli is obviously improved; the method comprises the following steps: designing 6-12 gene segments with overlapping sequences, splicing by adopting an overlapping extension PCR (Polymerase Chain Reaction) technology to obtain a full-length optimized gene, constructing the full-length optimized gene to an expression vector, and transforming the full-length optimized gene into host bacteria for induced expression; the expression product exists in the form of an inclusion body, and the natural conformation of the expression product is recovered through in-vitro renaturation; according to the method, high-efficiency expression and active preparation of the full-length human-derived III-type collagen in a prokaryotic system are realized.

The invention discloses a promoter mutant and an application of the promoter mutant in production of isoleucine. The invention provides a DNA molecule which is any one of the following: A1) a DNA molecule with a nucleotide sequence as shown in SEQ ID No.2; a2) is a variant which is obtained by substitution, deletion or addition of one or more nucleotides at other positions except the 66th nucleotide in the nucleotide sequence as shown in SEQ ID No.2, and the obtained DNA molecule has the same or enhanced promoter activity. Experiments prove that a series of promoter mutants with different strength and regulation characteristics are constructed to replace natural promoters, so that the transcriptional level of a target gene in a key period of fermentation is accurately improved, and the yield of the target gene is increased. The promoter engineering strategy provides a new direction for improving the production performance of industrial microorganisms by optimizing endogenous stress-resistant elements.

The invention relates to a self-adjuvant based on a virus source glycopeptide and an application of the self-adjuvant in preparation of a vaccine, the self-adjuvant is a glycopeptide fragment based on a varicella-zoster virus (VZV) source, and the self-adjuvant is a B cell epitope structural domain V50 glycopeptide (from 50 valine to 135 isoleucine, V50-I135) in glycoprotein E. The invention further relates to a preparation method of the self-adjuvant based on the virus source glycopeptide and application of the self-adjuvant based on the virus source glycopeptide in preparation of the vaccine. The V50 glycopeptide and the novel coronavirus RBD are subjected to fusion expression and then are coupled to the surfaces of the nanoparticles based on ferritin to form the self-adjuvant vaccine, so that the levels of RBD specific antibodies and pseudovirus neutralizing antibodies induced by the RBD nanoparticle vaccine can be remarkably enhanced, and the V50 glycopeptide has a synergistic effect in B cell response and T cell response of systemic systemic immunity and mucosal immunity at the same time. The immune protection effect of the novel coronavirus RBD nanoparticle vaccine is obviously improved.

According to the present invention, there is provided a pharmaceutical composition for use in a method of treating a wound in the skin of a subject and methods of using the pharmaceutical composition, the pharmaceutical composition comprising a tetrapeptide having the amino acid sequence U-XXGD-Z wherein G is used to denote amino acid Glycine and D is used to denote amino acid Aspartic acid, as per the internationally recognised single letter code for amino acids. X denotes an amino acid selected from the group consisting of Glutamic acid (E), Lysine (K), Leucine (L), Alanine (A), Isoleucine (I), Arginine (R) and mixtures thereof. At the N-terminal end, U is selected from the group consisting of H, -CO-R1, - SO2-R1 or a biotinyl group. At the C-terminal end, Z is selected from the group consisting of OH, O R1, NHR1 or NR1R2. R1 and R2 are independently selected from the group consisting of alkyl, aryl, aralkyl, alkylaryl, alkoxy, saccharide and aryloxy group, which may be linear, branched, cyclical, polycyclic, unsaturated, hydroxylates, carbonylated, phosphorylated and / or sulphurous, said groups comprising from 1 to 24 carbon atoms and being capable of including one or more heteroatoms O, S and / or N.

The application discloses a novel Rdl gene mutant with V332I mutation, and a method for detecting insect resistance to broflanilide. The gene mutant is characterized in that the base of the amino acid at the 332th position is mutated from GTT, GTC or GTA to ATT, ATC or ATA, and the encoded amino acid sequence is mutated from valine (V) in the wild type to isoleucine (I). The V332I mutation site can be used for molecular detection of insect resistance to broflanilide, and also provides an important reference for research and application of insecticides targeting the gamma-aminobutyric acid receptor encoded by the Rdl gene.

The invention discloses a self-assembled nano-capture antibacterial peptide KIL4 and a preparation method and application thereof, and belongs to the technical field of biology, and the amino acid sequence is shown as SEQ ID No.1. The preparation method comprises the following steps: adopting an alpha-spiral heptapeptide repetitive sequence (abcdefg) 4 template, and selecting lysine to provide positive charges at positions b and c; isoleucine and leucine are respectively filled to a position a and a position d to provide intermolecular hydrophobic force, and lysine and glutamic acid are selected to be respectively filled to a position e and a position g to provide intermolecular electrostatic force; the position f of the center of the hydrophilic surface of the polypeptide is filled with tryptophan to optimize the hydrophobicity of the polypeptide, on the basis, the sequence is repeated for four times, and the invention further discloses application of the polypeptide in preparation of drugs for treating gram-positive bacteria or / and gram-negative bacteria infectious diseases. The antibacterial peptide disclosed by the invention has dual effects of resisting bacteria and capturing bacteria, has excellent biocompatibility, and provides an effective technical support for developing novel antibacterial drugs.