195 results about "Isoleucine" patented technology

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 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 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.

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.

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 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 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.

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 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 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.

The invention relates to the technical field of enzyme engineering, in particular to a malic enzyme mutant and application thereof. Specifically, the malic enzyme derived from Escherichia coli is subjected to site mutation screening, and results show that after methionine at the 144th site is mutated into isoleucine (M144I), glutamine at the 253rd site is mutated into isoleucine (Q253I), and threonine at the 327th site is mutated into phenylalanine (T327F), the catalytic efficiency and the catalytic activity are obviously improved, which is of great significance to industrial application.

The present disclosure relates to: a protein variant; a polynucleotide encoding the protein variant; a Corynebacterium genus microorganism comprising at least one selected from the group consisting of the protein variant and the polynucleotide; and a method for producing L-isoleucine using the microorganism.

This invention relates to the field of bioengineering technology, specifically to a cis-epoxysuccinate hydrolase mutant and its applications. The cis-epoxysuccinate hydrolase mutant is obtained by single-point or multi-point mutations at positions 127 and 141 of the amino acid sequence of the wild-type cis-epoxysuccinate hydrolase shown in SEQ ID NO. 1. The single-point mutation involves replacing valine at position 127 with isoleucine, or replacing aspartic acid at position 141 with threonine. The cis-epoxysuccinate hydrolase mutant obtained by this invention exhibits high thermal stability, significantly improving the service life of the cis-epoxysuccinate hydrolase in the industrial production of D(-)-tartaric acid.

The invention belongs to the technical field of biological medicine and molecular biology, and provides a hypertrophic cardiomyopathy virulence gene MYH7c.794Cgt; the invention relates to T (p.Thr265Ile) and an application thereof. The MYH7 gene mutation is located on the ninth exon, the 794th base is mutated from C to T, namely ACC is mutated to ATC, and the 265th amino acid in the coded amino acid sequence is mutated from threonine to isoleucine. The mutation induces cardiac hypertrophy by disrupting energy metabolism-this defect occurs prior to the occurrence of systolic dysfunction. Along with increasingly prominent status of precision medicine in cardiovascular treatment, a treatment strategy aiming at an upstream pathological process (such as energy homeostasis and mitochondrial dysfunction) provides a way with a wide prospect for preventing and treating MYH7-related hypertrophic cardiomyopathy. MYH7 gene screening has important values in the aspects of promoting early diagnosis, guiding timely treatment intervention and realizing risk-based prevention and management.

This invention discloses the application of a branched-chain amino acid (BCAA) restricted diet in the preparation of drugs for treating liver metastases of tumors. Through mouse model experiments, this invention found that restricting the intake of BCAAs (valine, isoleucine, and leucine) in the diet, or using the SCD1 inhibitor A939572, can significantly inhibit liver metastases of tumors, especially pancreatic cancer liver metastases. Experimental results show that a BCAA restricted diet or SCD1 inhibitor can reduce the number and volume of liver metastases and inhibit their growth. This invention also reveals its mechanism of action: BCAA restriction reduces the propionylation modification of SREBP1, downregulates the transcriptional expression of its target gene SCD1, and thus reduces lipid synthesis, thereby exerting an anti-tumor liver metastasis effect. This invention provides a novel dietary intervention strategy and drug target for the treatment of liver metastases of tumors.

The present invention relates to the field of polypeptide compositions, and specifically relates to a polypeptide metal chelate and the use thereof in the field of cosmetics. The polypeptide metal chelate is formed by means of the chelation of a polypeptide compound with a metal ion compound. A structure of the polypeptide compound is: [γ-Glu]n-AA, wherein n≥1, and AA is selected from glycine, alanine, valine, leucine, isoleucine, methionine (Met), proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine or histidine. The polypeptide zinc chelate prepared by the present invention has significant oil-controlling and anti-inflammatory effects, and can be compounded with other raw materials to prepare cosmetics with oil control and acne removal effects.

The application discloses an L-aspartate alpha-decarboxylase with improved substrate tolerance, and the L-aspartate alpha-decarboxylase is derived from Bacillus subtilis and is subjected to site-directed mutation, i.e., phenylalanine at the 4th site is changed into tryptophan, isoleucine at the 33rd site is changed into alanine, and isoleucine at the 88th site is changed into tryptophan, so as to obtain an enzyme mutant; the mutant is recombined into E. coli, and after expression is induced, the mutant catalyzes the substrate L-aspartate to generate beta-alanine. When the substrate addition concentration of the whole cell catalytic system is 60 g / L, the conversion rates of the three enzyme mutants T4W, I33A and I88M can reach about 90%, and the yields are 1.2, 1.3 and 1.2 times of that of the unmutated strain respectively, and the substrate tolerance is obviously improved; the combined mutation also has a certain improvement on the substrate tolerance, and the finding has important research value for industrial preparation of beta-alanine.

This invention discloses a mutant, gene, and recombinant bacteria of a highly thermostable single-chain sweet protein. The mutant is characterized by the following amino acid sequences shown in SEQ ID NO.1: isoleucine (I) at position 5 is mutated to glutamic acid (E), glutamic acid (E) at position 23 is mutated to alanine (A), isoleucine (I) at position 26 is mutated to arginine (R), cysteine ​​(C) at position 41 is mutated to alanine (A), tyrosine (Y) at position 65 is mutated to isoleucine (I), glycine (G) at position 83 is mutated to arginine (R), and asparagine (N) at position 90 is mutated to glutamic acid (E). Based on structural analysis and computationally assisted design for protein stability, this invention achieves site-directed mutagenesis of the single-chain sweet protein, resulting in a highly thermostable mutant. Compared to the original single-chain sweet protein, the thermostable mutant of this invention exhibits higher T... m It was heated by more than 20.4°C while maintaining its sweetness.

This invention discloses the application of the NCgl0214 protein and its biomaterials in the production of L-isoleucine, belonging to the field of biotechnology. The technical problem solved by this invention is how to increase the yield of L-isoleucine. The sequence of the protein disclosed in this invention is SEQ ID No. 4 or SEQ ID No. 2. Replacing the coding gene of the protein shown in SEQ ID No. 2 in the starting organism cell with the coding gene of the protein shown in SEQ ID No. 4, or increasing the content or activity of the protein shown in SEQ ID No. 2 or SEQ ID No. 4 in the starting organism cell, can both increase the yield of L-isoleucine.

The invention provides a method for detecting amino acid in a compound encephalokinin injection by using an LC-MS (Liquid Chromatography-Mass Spectrometry) method, which has the characteristics of simplicity and convenience in operation, and good precision, stability and recovery rate. The method can be used for detecting the content of 13 amino acids in the compound brain peptide injection, including histidine, phenylalanine, lysine, tyrosine, asparagine, methionine, valine, leucine, serine, arginine, proline, alanine and isoleucine. The detection method is high in detection sensitivity and can be applied to internal quality component research, intermediate component control and quality identification of the product. The detection method can also be used for evaluating the inherent quality of the compound encephalokinin injection, further ensuring the stability of the inherent quality of the product and providing technical reference.

The present invention relates to a modified dehydrogenase, wherein one or more amino acid residues of the dehydrogenase are modified as compared to an unmodified dehydrogenase, and wherein the modified dehydrogenase has an increased ratio of leucine dehydrogenase or isoleucine dehydrogenase activity to valine dehydrogenase activity as compared to the unmodified dehydrogenase, and applications thereof.

Method of feeding young pigs involves feeding young pigs with complete mixed feed. Wherein, isoleucine levels in the composition of mixed feed are specifically regulated by introducing synthetic isoleucine. The ratio of standardized ideal digestible (SID) isoleucine to lysine in the diet is 0.55. The specified ratio is maintained in the diets of young pigs during the nursery after weaning, from 24 to 70 days of age.

Methods and compositions for treating hair, such as to reduce split ends, seal cracks in hair cuticles, reduces damage to hair, and / or reduce frizziness and / or hair fly-aways. The methods and compositions use a combination of hydroxypropyl guar hydroxypropyltrimonium chloride, Argania spinosa kernel oil, guar hydroxypropyltrimonium chloride, and algin. In some instances, the composition further contains bis-aminopropyl diglycol dimaleate. In some instances, the composition further contains a fructooligosaccharide and / or Beta vulgaris root extract. In some instances, the composition further contains arginine, aspartic acid, glycine, alanine, serine, valine, proline, threonine, isoleucine, histidine, and / or phenylalanine.

The invention provides a melittin polymer, which is formed by at least connecting disulfide bonds between two melittin variant molecules after a melittin variant is formed by mutating alanine at the fourth site of an amino acid sequence of a melittin monomer into cysteine and mutating isoleucine at the twentieth site into cysteine in the amino acid sequence of the melittin monomer. The preparation method of the melittin polymer comprises the following steps: obtaining a melittin variant through escherichia coli recombinant expression, and purifying and oxidizing the obtained melittin variant through a nickel column to obtain the melittin polymer, and carrying out gel filtration chromatography on the obtained melittin polymer to obtain the purified melittin polymer. The invention also provides an application of the melittin polymer, and the melittin polymer is used for preparing antibacterial drugs or antibacterial feed additives. The prepared melittin polymer can effectively reduce the toxicity to red blood cells, has relatively strong environmental responsiveness and stability, and can effectively prolong the antibacterial aging.

It provides an improved immunoglobulin variable domain. [Solution] A VH domain comprising: (i) the amino acid residue at position 112 is either K or Q, and / or; (ii) the amino acid residue at position 89 is T, and / or; (iii) the amino acid residue at position 89 is L, the amino acid residue at position 110 is either K or Q, and (iv) in each of (i) to (iii), the amino acid at position 11 is preferably V, and the VH domain contains a C-terminal extension (X)n [wherein n is 1 to 10, preferably 1 to 5, for example 1, 2, 3, 4, or 5, and each X is a (preferably native) amino acid residue, independently selected from alanine (A), glycine (G), valine (V), leucine (L), or isoleucine (I), preferably independently selected from the group consisting of these].

The present invention relates to a nutritional vitamin complex for pets intended to improve the fur and skin quality of pets such as dogs and cats. The composition of the complex contains omega-3, curcumin, piperine, biotin (vitamin H or vitamin B7), vitamin B2 (riboflavin), vitamin B3 (nicotinic acid or niacin), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine), vitamin B12 (cyanocobalamin), folic acid (vitamin B9), vitamin E (alpha-tocopherol), vitamin C, zinc (zinc glycine chelate), coenzyme Q10, hydrolysed type II collagen, astaxanthin, DL-methionine, selenium, L-glycine, L-proline, L-phenylalanine, L-leucine, L-isoleucine, L-histidine, L-arginine, L-lysine, L-tyrosine, resveratrol, and a flavouring agent.

The invention discloses a preparation method and application of a compound amino acid injection, and the preparation method comprises the following steps: adding water for injection into a closed container filled with protective gas; amino acids including tyrosine, leucine, isoleucine, phenylalanine, aspartic acid, glutamic acid, methionine, tryptophan, valine, threonine, histidine, alanine, glycine, arginine, lysine acetate, proline, serine and cysteine are sequentially added according to the following sequence, and liquid medicine is obtained; and heating and sterilizing the liquid medicine to obtain the compound amino acid injection. Specific amino acid components are added into the closed container filled with protective gas according to a specific sequence, a good anti-oxidation effect can be achieved under the condition that an antioxidant and an adsorbent are not added, and the 18-component compound amino acid injection which is high in active component content, low in impurity content, good in product quality stability and high in clinical use safety is obtained.