290 results about "Valine" patented technology

The invention discloses a cyclic nonapeptide with repairing and anti-oxidation effects and application of the cyclic nonapeptide, the amino acid sequence of the cyclic nonapeptide is cyclic (arginine-glycine-aspartic acid-serine-arginine-lysine-valine-lysine-serine), the prepared cyclic nonapeptide has the repairing and anti-oxidation effects, and the cyclic nonapeptide has the repairing and anti-oxidation effects. The composition can be applied to preparation of cosmetics with repairing and / or anti-oxidation effects.

The invention discloses a hydrogel patch for gastric perforation repair and a preparation method thereof, and belongs to the technical field of biomedical materials. The preparation method comprises the following steps: dissolving acryloyl valine, acrylic acid, methylene bisacrylamide, a compound A and a photoinitiator in an alcohol solvent, and defoaming to obtain a precursor solution; and placing the precursor solution in a mold, carrying out ultraviolet-induced curing, soaking the obtained hydrogel in a hydrochloric acid solution, and replacing the alcohol solvent to obtain the hydrogel patch for gastric perforation repair. The hydrogel patch provided by the invention has the advantages of strong acid corrosion resistance, good biocompatibility, low swelling ratio, stable adhesion performance in a fluctuating pH environment and the like. The tough and stable adhesion performance ensures that the hydrogel can be permanently and reliably adhered to a gastric perforation part in a dynamic gastric acid environment, and a stable platform is provided for drug delivery, so that the surgical operation time is expected to be shortened, and wound healing is promoted.

The invention relates to the technical field of biological catalysis, and discloses an M88V mutant enzyme for preparing rebaudioside I. The M88V mutant enzyme is obtained by the following mutations generated by UGT76G1: M88V: methionine of the 88th amino acid sequence of UGT76G1 is mutated into valine. Aiming at the technical bottlenecks of low RI yield and poor selectivity in the existing RA biotransformation process, an efficient solution is provided for the UGT76G1 mutant developed by the invention. The mutant can specifically catalyze conversion from RA to RI, and the conversion rate of a target product is remarkably increased to 65% or above from general less than 7%. The excellent catalytic performance of the catalyst is verified in milliliter-level to upgraded reaction systems, the key problems of conversion efficiency and process amplification are solved, and a foundation is laid for large-scale green manufacturing of a high-added-value product RI.

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 a valine production strain and a construction method and application thereof, a designed acetohydroxy acid synthase mutant is that the 88th basic group of an ilvB gene is changed from a to c, the 382nd basic group is changed from a to g, the 413th basic group is changed from c to t, the gene sequence of a designed artificial operon comprises a promoter, an ilvB (A138V) gene or ilvB (Q30K, S128G, A138V) gene of coding mutated acetohydroxy acid synthase, and an ilvN (G20D, I21D, I21D, I21D, I21D, I21D, I21D, I21D) gene. I22F) gene, a pyk gene for coding pyruvate kinase, and a terminator; by designing a specific acetohydroxyacid synthase mutant and related biological materials and artificial operon, the strain constructed by directional modification of the strain by using a pK18mobsacB system gene editing technology based on allele exchange has the advantages of good genetic stability, high fermentation yield and the like, and valine can be stably produced.

The invention provides a valine production strain as well as a construction method and application thereof, the strain is constructed by utilizing a CRIPSR / Cas9 system gene editing technology based on allele exchange, an artificial operon is designed and constructed, the artificial operon is constructed at a ygaY site, a strong promoter Ptrc is used for controlling ilvIH (G14N S17F)-pykF to carry out synchronous multi-copy expression, and the valine production strain can be used for producing valine. On the basis of the strain, an artificial operon is constructed at an ycgH site, a strong promoter Ptrc is used for controlling ilvC-ilvD to carry out synchronous multi-copy expression, meanwhile, feedback inhibition of valine on ilvIH is relieved, and an ilvIH natural promoter is replaced by the strong promoter Ptrc, so that more pyruvic acid flows to valine; the constructed strain does not contain plasmids, has no defects, does not need induction, has the advantages of good genetic stability, high fermentation yield and the like, and can be used for efficiently synthesizing valine from the beginning by taking glucose as a substrate.

The present disclosure is directed to HLA class II molecules having a higher affinity for CD4 than naturally occurring HLA class II molecules. In certain aspects, the HLA class II molecule comprises a DQ beta chain having (i) an amino acid other than leucine at a position corresponding to amino acid residue 114 of SEQ ID NO: 1, (ii) an amino acid other than valine at a position corresponding to amino acid residue 143 of SEQ ID NO: 1, (iii) or both (i) and (ii). Certain aspects of the present disclosure are directed to nucleic acid molecules encoding the HLA class II molecules, vectors comprising the nucleic acid molecule, cells comprising the same, and methods of use thereof.

The invention discloses a salicylic acid decarboxylase mutant and application of the salicylic acid decarboxylase mutant in degradation of salicylic acid. The mutant is obtained by carrying out site-specific modification on salicylic acid decarboxylase NahG, and specifically, valine at the 46th site, tyrosine at the 380th site and leucine at the 382nd site of an amino acid sequence shown in SEQ ID NO.2 are mutated into cysteine, phenylalanine and phenylalanine at the same time. The mutant shows remarkably improved catalytic efficiency, and salicylic acid can be efficiently and thoroughly decarboxylated and converted into catechol under mild conditions. The invention also provides a coding gene, a recombinant vector and an engineering bacterium of the mutant. The mutant not only can be used for efficient bioremediation of salicylic acid pollution, but also can effectively break through and accelerate a naphthalene catabolism pathway due to the characteristic of directionally generating catechol, and has important application value in the fields of environmental pollution abatement and biological catalysis.

The present specification relates to a composition including a new amide-based compound derived from an amino acid structure such as valine, leucine, phenylalanine, proline, pipecolic acid, or the like, wherein the composition exhibits a skin anti-aging or skin reverse-aging effect by restoring the size and number of dendrites of aged melanin-producing cells to those of young cells. As a result, the composition may exhibit a skin brightening effect by inhibiting the amount of melanin produced in the melanin-producing cells.

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 invention discloses a phytase mutant AppA as well as a coding gene, a preparation method and application thereof. The phytase mutant AppA is obtained by mutating amino acids at the 137th site, the 185th site and the 255th site of wild type phytase AppA from asparagine, aspartic acid and tyrosine into valine, asparagine and aspartic acid respectively; the amino acid sequence and the nucleotide sequence of the gene are SEQ ID NO.1 and SEQ ID NO.2 respectively. The catalytic efficiency of the mutant enzyme AppA provided by the invention on sodium phytate is improved by 2.5 times compared with that of a wild enzyme AppA; under the condition of 70 DEG C, the half-life period of the mutant enzyme AppA is 3.4 times that of the wild enzyme AppA. The mutant enzyme AppA has the characteristic of high enzyme activity under a high-temperature condition, which indicates that the mutant enzyme AppA has an important application prospect in industrial production of a feed in which phytic acid needs to be degraded under the high-temperature condition.

The invention relates to the technical field of biomedical materials, in particular to a sodium hyaluronate composite solution for relieving skin aging and a preparation method thereof, the sodium hyaluronate composite solution comprises sodium hyaluronate, taurine, proline, glutamic acid, glycine and valine; sodium hyaluronate has a specific molecular weight, the composite solution has a specific pH value and osmotic pressure, and all the components have a synergistic effect, so that a moist environment is provided for skin, free radicals are removed, collagen synthesis is promoted, and aging phenomena such as skin laxity and wrinkles are improved. The composition can maintain skin moisture for a long time, scavenge free radicals, resist oxidation and promote collagen synthesis to improve skin aging, the preparation process guarantees stable components, the solution is matched with the physiological environment of the skin, and the composition is non-irritant, safe to use and good in anti-aging effect.

The application belongs to the technical field of protein extraction, and provides a method for improving water holding property and oil holding property of peony seed protein, the core of the method is that before the extraction of the peony seed protein, the peony seed is pretreated by the following method: the peony seed meal is subjected to steam explosion treatment under the condition of 0.4-1.2 Mpa and 60-150 s, preferably 0.8 Mpa and 100 s, to obtain the steam exploded peony seed, and the sample after the steam explosion is subjected to drying treatment; preferably heat pump drying. The peony seed protein prepared by the method has obviously improved water holding property, oil holding property, foaming property, foam stability, emulsifying property and emulsion stability; the valine is increased by 8.58%, the leucine is increased by 6.63%, and the tyrosine is increased by 10.65%; the extraction rate of the seed protein is 76.82%, and the extraction effect is excellent.

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 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.

This invention belongs to the field of biomedical technology and provides a polypeptide with ATG8 protein binding activity, comprising the following structure: X1-X2-X3-X4-X5-X6-X7; wherein: X1, X2, and X3 are independently selected from glutamic acid or are absent; X4 is selected from tryptophan, phenylalanine, or leucine; X5 is valine; X6 is selected from leucine, isoleucine, or valine; and X7 is selected from valine, tryptophan, phenylalanine, or tyrosine. Compared with existing autophagy inhibitors, this polypeptide has the following superior pharmacokinetic potential and development flexibility in terms of target selection, binding strength, and mechanism of action: the short sequence not only reduces synthesis costs but also leaves more room for modification, which is expected to significantly improve the metabolic stability and drug-likeness potential of the polypeptide; it can serve as a highly efficient ATG8 targeting ligand and can be widely used in the construction of biochemical probes, screening of PPI competitive inhibitors, and the development of targeted delivery systems.

The present disclosure relates to HLA class II molecules having higher affinity for CD4 than naturally occurring HLA class II molecules. In certain aspects, the HLA class II molecules comprise a DQ beta chain having: (i) an amino acid other than leucine at a position corresponding to amino acid residue 114 of SEQ ID NO: 1, (ii) an amino acid other than valine at a position corresponding to amino acid residue 143 of SEQ ID NO: 1, or (iii) both (i) and (ii). Certain aspects of the present disclosure relate to nucleic acid molecules encoding the HLA class II molecules, vectors comprising the nucleic acid molecules, cells comprising them, and methods of using the same.

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.

Provided is a cyclic peptide, which has a sequence of cyclo(X1X2X3X4X5X6), wherein X1 is asparagine; X2 is glycine or sarcosine; X3 is arginine; X4 is selected from a group consisting of threonine, tyrosine, and phenylalanine; X5 is lysine; and X6 is selected from a group consisting of tyrosine, valine, and glutamic acid. Provided is a preparation method for the cyclic peptide. Provided is a complex, comprising the cyclic peptide, a linker, and a chelating agent. Provided is a use of the complex as a radionuclide-labeled targeting molecule. Provided is a radionuclide labeling method, comprising bringing a complex that chelates a radionuclide into contact with an object to be labeled by the radionuclide.

The invention relates to an N-terminal acetylation and C-terminal ethylamine dual-modified LMN-NKA polypeptide derivative or a pharmaceutically acceptable salt and a preparation method thereof. The chemical name of the LMN-NKA polypeptide derivative is N-acetyl-L-aspartic acid-L-lysine-L-phenylalanine-L-valine-glycine-N-methyl-L-leucine-L-n-leucine-ethylamine, and the structural general formula of the LMN-NKA polypeptide derivative is Ac-Asp-Lys-Phe-Val-Gly-NMe-Leu-Nle-NHCH2 CH3, and the structural general formula of the LMN-NKA polypeptide derivative is shown in the description. According to the dual-modification strategy, the binding activity of the NK2 receptor can be specifically reserved, the enzymolysis stability is high, the transmembrane efficiency is high, the lipid solubility is high, and the physicochemical property is stable. The LMN-NKA polypeptide derivative or the pharmaceutically acceptable salt thereof disclosed by the invention is particularly suitable for preparing a medicine for treating diseases related to an NK2 receptor.

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.

A recombinant adeno-associated virus (rAAV) vector comprising an AAVhu68 capsid produced in a production system comprising a nucleotide sequence of SEQ ID NO: 1, or a sequence at least 75% identical thereto which encodes SEQ ID NO:2. The AAVhu68 capsid comprises subpopulations of highly deamidated asparagine residues in asparagine-glycine pairs in the amino acid sequence of SEQ ID NO: 2. Also provided are compositions containing the rAAV and uses thereof. Additionally, rAAV having an engineered AAV capsid comprising at least one subpopulation of vp1 or vp2 proteins having a Val at amino acid position 157 with reference to the AAVhu68 vp1 numbering are provided.

The invention discloses a pharmaceutical composition. The pharmaceutical composition comprises a medicine granulated substance containing 4-((L-valyl) oxy) butyric acid and an excipient granulated substance. When the pharmaceutical composition is combined and mixed with water, the excipient particles rapidly dissolve to form a viscous solution in which the pharmaceutical granules are suspended. The pharmaceutical granulate provides a palatable oral pharmaceutical composition.

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 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.