246 results about "Methionine biosynthesis" patented technology

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 invention relates to the field of plant molecular biology and forest genetic engineering, and particularly provides a PagRAP2.3 protein point mutant and application thereof in drought resistance of poplar. The mutant PagRAP2.3 MA is obtained by mutating methionine at the first site and cysteine at the second site of a wild type PagRAP2.3 protein into methionine and alanine. The invention further discloses a preparation method of the mutant PagRAP2.3. An expression vector containing the PagRAP2.3 MA gene is constructed, poplar 84K is transformed through an agrobacterium-mediated method, and a transgenic line with stable expression is obtained. Functional verification results show that overexpression of PagRAP2.3 MA can significantly increase the plant height of the poplar and promote plant growth, but the sensitivity to moisture is enhanced under drought stress. The mutant can be used for regulating and controlling the growth and development of forest trees and evaluating the drought resistance, and has a forestry breeding application prospect.

The invention belongs to the technical field of biological detection, and particularly relates to a method for synchronously and quantitatively detecting various folic acid metabolism related substances in trace plasma or serum, which comprises the following steps of: detecting a pretreated trace plasma or serum sample by adopting a liquid chromatography-tandem mass spectrometry method; the following nine folic acid metabolism related substances are synchronously and quantitatively detected: 5-formyl tetrahydrofolic acid, folic acid, 5-methyl tetrahydrofolic acid, S-adenosine-L-methionine, S-adenosine-L-homocysteine, vitamin B12, pyridoxamine, pyridoxine and pyridoxal. The invention further relates to application of the detection method in related detection of child neurodevelopment. According to the detection method, only trace plasma or serum is used, methotrexate is used for replacing an expensive isotope internal standard for more economical detection, and nine folate metabolism related substances can be accurately quantified at the same time. Therefore, the detection method disclosed by the invention has important clinical significance and wide market application prospect.

The invention discloses a method for improving the fermentation performance of clostridium aerovorans and application of the clostridium aerovorans, and according to the method, an effective amount of methionine or a derivative thereof is added into a fermentation culture medium of the clostridium aerovorans to completely replace expensive complex organic nitrogen sources such as yeast extracts. The method successfully solves the three technical bottlenecks of slow biomass accumulation, low ethanol yield and dependence on expensive nitrogen sources in the fermentation process of the clostridium aerovorans by utilizing synthesis gas or CO2 / H2 mixed gas. Experiments prove that methionine or a derivative thereof can synergistically promote growth metabolism of thalli and a synthesis path of a product, so that the gas conversion efficiency of a carbon source is remarkably improved and metabolism is guided to flow to ethanol synthesis while the growth rate and the final biomass of the thalli are improved, and thus the production capacity of alcohols is synchronously enhanced. The method is simple in process and remarkable in effect, and an efficient and economical new strategy is provided for reducing the production cost of biofuel and promoting industrial application of a synthesis gas biorefinery technology.

The invention provides an application of synbiotics in preparation of a composition for improving glucagon-like peptide-1 (GLP-1). The composition comprises litchi polyphenol, probiotics and methionine. The probiotics comprise bifidobacterium animalis BCRC910645, bifidobacterium longum BCRC910812, or a combination of the bifidobacterium animalis BCRC910645 and the bifidobacterium longum BCRC910812, so that the content of the glucagon-like peptide-1 is increased.

The invention provides a recombinant O-succinyl-L-homoserine mercaptotransferase mutant, a coding gene thereof, a recombinant vector containing the coding gene of the mutant, a recombinant genetically engineered bacterium obtained by converting the recombinant vector, and application of the recombinant O-succinyl-L-homoserine mercaptotransferase mutant in preparation of L-methionine. The novel recombinant O-succinyl-L-homoserine mercaptotransferase mutant with high activity and high selectivity is used as a catalyst to be applied to catalysis of O-succinyl-L-homoserine for synthesis and preparation of L-methionine, a catalytic reaction system is optimized, the feed ratio and reaction conditions in the reaction are finely regulated and controlled, and the yield of L-methionine is increased. The recombinant O-succinyl-L-homoserine mercaptotransferase mutant has high enzyme activity under the optimal reaction condition, the catalytic efficiency is further improved, the purposes of reducing cost and improving efficiency are achieved, and the method has important significance in promoting industrial application of biological catalysis preparation of L-methionine.

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.

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 application discloses application of a combined inhibitor in associated gold-silver-lead-zinc sulfide ore flotation separation, wherein the combined inhibitor is a combination of zinc sulfate and methionine, and the mass ratio of the two combined is 2:1; the combined inhibitor is used to realize associated gold-silver-low-copper-lead-zinc polymetallic sulfide ore flotation separation in a low-alkali environment, has a good separation effect, high concentrate grade, effectively reduces the zinc content of lead concentrate, improves the gold and silver recovery rate in the lead concentrate, and has important significance for improving the quality and efficiency of associated gold-silver-low-copper-lead-zinc polymetallic sulfide ore flotation separation. In addition, the methionine in the combined inhibitor is a small-molecule organic substance, is non-toxic and non-polluting, and is easy to degrade, thereby avoiding the problems of traditional inhibitors, such as toxicity, environmental unfriendliness and human body unfriendliness. The combined inhibitor has small dosage, stable effect, and good process application prospect.

The invention relates to a protein consisting of an amino acid sequence in which at least one modification selected from the group consisting of the following [1] to [7] is introduced in the amino acid sequence represented by SEQ ID NO: 1: [1] a modification in which the amino acid residue at a position 103 is substituted with a lysine residue, [2] a modification in which the amino acid residue at a position 76 is substituted with a cysteine residue, [3] a modification in which the amino acid residue at a position 144 is substituted with a cysteine residue, [4] a modification in which the amino acid residue at a position 134 is substituted with a glycine residue, [5] a modification in which the amino acid residue at a position 222 is substituted with a methionine residue, [6] a modification in which the amino acid residue at a position 73 is substituted with a glutamine residue, and [7] a modification in which the amino acid residue at a position 203 is substituted with a threonine residue.

The invention belongs to the technical field of enzyme gene engineering, and particularly relates to a methionine gamma-lyase mutant with improved enzyme activity and application thereof. The methionine gamma-lyase mutant CqMGLV160I / V265I with high activity is obtained by taking methionine gamma-lyase (CqMGL) which is derived from Calorama quimayensis and of which cysteine residues at 116 sites are replaced by histidine residues as a parent and carrying out site-specific mutagenesis on amino acid residues at key sites through transformation. The methionine gamma-lyase mutant CqMGLV160I / V265I with high activity can be obtained by using the methionine gamma-lyase mutant CqMGLV160I / V265I as the parent. By adopting the CqMGLV160I / V265I mutant disclosed by the invention, the conversion rate of enzyme catalysis can be improved, allicin is efficiently synthesized, and the mutant is successfully applied to the aspects of food, feed, chemical industry, medicine preparation and the like.

The present invention concerns the recovery of methionylmethionine from aqueous alkali ions containing media by intermediate formation of Bis(methionyl)-diketopiperazine.

The invention provides a dipeptide capable of rapidly supplementing methionine and application thereof, and belongs to the field of nutritional and functional food. The problems of quickly supplementing methionine and promoting lactation are solved. The preparation method comprises the step of preparing the dipeptide GM of which the C terminal is methionine through solid-phase synthesis. The dipeptide GM can be used for supplementing methionine, and it is verified that compared with EM, KM and MM, the dipeptide GM has the higher methionine absorption rate in cells based on the PepT1 vector. The dipeptide GM can also be used for promoting lactation, and it is verified that the dipeptide GM has a better lactation promoting effect compared with EM, KM and MM.

The present invention relates to a cosmetic composition, advantageously an eco-biological cosmetic composition, comprising: - polyglutamic acid or a salt thereof; and - at least one peptide derivative represented by the general formula (I) in which: - R1 represents a hydrogen atom, an acyl radical or an acyloxy radical; and - R2 represents the side chain of an alpha-amino acid chosen from the group consisting of phenylalanine, glutamic acid, arginine, cysteine, methionine, histidine and tyrosine. The present invention also relates to the use of said cosmetic composition for combating skin redness and / or skin aging; to its use for preventing and / or combating cutaneous vascular hyperproliferation and / or cutaneous inflammation and / or rosacea; and to a method for selecting compounds suitable for preventing and / or combating these pathologies.

The present invention relates to a compound, the compound is a compound represented by a formula (I), or an isomer, an isotope derivative, a polymorphic substance, a prodrug, a pharmaceutically acceptable salt or a solvate thereof, and the definitions of A1, B1 and L are the same as the definitions in the specification. Also provided are pharmaceutical compositions and compounds of formula (I) for use in methods of treating related diseases by inhibition of MAT2A, including some cancers in which a gene encoding a methylthioadenosine phosphorylase (MTAP) is deleted and / or not fully functioning.

The application provides a method for preparing cross-linking enzyme based on a tyrosinase mutant, the cross-linking enzyme and application thereof. The tyrosinase mutant is mixed with an ultrasonic broken solution of S-adenosylmethionine synthetase containing a tyrosine tag to obtain water-insoluble cross-linking enzyme particles, the cross-linking enzyme is collected by centrifugation or filtration and the like, and enzymatic conversion is carried out. It is found that the cross-linking enzyme of S-adenosylmethionine synthetase can be continuously and stably used for 6 batches, and the activity retention is 85%. The cross-linking enzyme particles prepared by the method have the characteristics of easy recovery, reusability and low cost, and have good industrial application value.

The present invention relates to peptide conjugates that comprise a plant-derived oligopeptide capable of crossing the blood-brain barrier (BBB) and a therapeutic or diagnostic agent. The BBB-penetrating oligopeptide is an oligopeptide according to Formula I, Asp–R2–Gly–Leu–R5–R6–R7–Leu–Gly–R10–R11–R12, wherein R2 represents Arg, Lys, Cyt, D-Arg or Orn; R5 represents Phe, Arg, Lys, His, Trp, Tyr, D-Tyr, D-Phe, Orn, 4-aminophenylalanine or 3-phenylpropionate; R6 represents Pro, Leu, Glu or Lys; R7 represents Phe or Trp; R10, R11 and R12 each independently represent Lys, Arg or Orn; or an oligopeptide according to Formula II, Glu–R2'–R3'–Gly–R5'–R6'–Glu–R8'–R9'–R10'–Glu–R12'–Leu–Pro–Gly, wherein R2', R3', R8', R10' and R12' each independently represent Lys, Arg or Orn; R5' represents Phe, Ile, Arg, Lys, His, Trp, Tyr, D-Tyr, D-Phe, 4-aminophenylalanine, or 3-phenylpropionate; R6' represents Met, Leu, Ile, Asn, norleucin, D-norleucin, seleno- methionine or D / L-2-hydroxy-(4-methylseleno)butanoic acid; and R9' represents Leu or Ile. The conjugates comprising a BBB-penetrating oligopeptide compound and a therapeutic agent can be used in treatments for diseases of the central nervous system (CNS). Furthermore, conjugates with a BBB-penetrating oligopeptide compound and a diagnostic agent can be used in both in vivo and in vitro diagnostic methods.

The invention relates to a preparation of an antibody drug, which belongs to the field of biological medicines, is used for a preparation of a high-concentration antibody drug with an anti-oxidation requirement, and also has an anti-degradation capability. The preparation contains 20 mmol / L to 30 mmol / L of L-methionine and 200 mmol / L of trehalose, and is particularly suitable for being used for preparing Jukoulikumab, omaszumab and cetuximab. The preparation not only has a better anti-oxidation effect, but also can realize a synergistic stabilization effect by combining high-concentration L-Met with 200 mM trehalose, has anti-degradation ability, is widely applicable to various therapeutic antibodies, and provides an extensible solution for improving the stability and shelf life of a high-concentration biological preparation.

This invention relates to the field of lyophilized formulation technology, specifically disclosing an esupagglutide α-nano-lyophilized micelle and its preparation method. The micelles of this invention utilize polylactic-co-hydroxyacetic acid copolymer and sodium phosphatidylglycerol as micelle carriers, with arginine and cysteine ​​providing branching synergistic effects. Homogenization via film formation and low-temperature lyophilization yield lyophilized nano-micelle powder. The nano-micelle powder reduces protein oxidative decomposition during lyophilization, decreases impurity fragments, and reduces various non-fucose glycosylation, basic components (succinimide, methionine oxidation products), N-terminal deletion, Asn deamidation, and Met and Trp residue oxidation impurities that affect product quality. Product quality analysis and animal experiments after reconstitution show good resistance to impurities and degradation risk. The reconstituted esupagglutide α-nano-micelle system exhibits better stability and sustained-release properties, enhancing the hypoglycemic sustained-release effect 72 hours after injection, significantly improving upon conventional non-micelle formulations.

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 invention discloses a multi-enzyme complex of S-adenosylmethionine decarboxylase / spermine synthetase and an application of the multi-enzyme complex in production of spermine. Belongs to the technical field of enzyme engineering. The purpose of the present invention is to increase the yield of spermine. The invention provides a multi-enzyme complex of S-adenosylmethionine decarboxylase / spermine synthetase. The multi-enzyme complex is obtained by connecting the S-adenosylmethionine decarboxylase and the spermine synthetase through a flexible linker. And a theoretical basis is provided for preparation of spermine.

The application relates to a reagent combination for detecting depression, a manufacturing method, a detection system and application thereof, and belongs to the technical field of instrument detection. The reagent combination for detecting depression comprises a calibrator, a quality control sample and an extraction solution of a to-be-detected compound serving as a biomarker; wherein the to-be-detected compound is at least three kinds selected from 5-hydroxyanthranilic acid, methionine, gamma-aminobutyric acid, 3,4-dihydroxyphenylacetic acid, 2-picolinic acid, quinolinic acid, kynurenine, 5-hydroxytryptamine, 3-hydroxykynurenine, 3-hydroxyanthranilic acid, dopamine and norepinephrine. The reagent combination for detecting depression and the detection system can significantly improve the accuracy of diagnosis, are convenient to detect, have good repeatability of detection data, are high in specificity, and are accurate in clinical diagnosis results.

The invention discloses a preparation method of a biomass-based slow-release agent for repairing polycyclic aromatic hydrocarbon polluted underground water, which comprises the following steps: 1, preparation of soybean milk fermentation liquor: weighing soybeans, soaking the soybeans in ultrapure water according to a solid-to-liquid ratio of 1: 20-1: 50 for 12-48 hours, pulping, and adding ultrapure water until the volume is 500mL to obtain a soybean milk matrix; inoculating 10mL of polycyclic aromatic hydrocarbon polluted underground water indigenous microorganism bacterial liquid into the soybean milk matrix, and carrying out closed fermentation under a constant-temperature oscillation condition, 2, preparation of a multifunctional composite slow-release agent: weighing 35-60 parts by weight of FeSO4. 7H2O, 1-5 parts by weight of rhamnolipid, 5-10 parts by weight of humic acid, 1-5 parts by weight of methionine, 5-10 parts by weight of peanut peptide, 1-10 parts by weight of soybean lecithin, 3-10 parts by weight of a yeast extract and 40-60 parts by weight of the soybean milk fermentation broth prepared in the step 1; the method has the beneficial effects that the degradation efficiency on organic pollutants such as polycyclic aromatic hydrocarbon is remarkably enhanced, and a reliable material basis and theoretical support are provided for engineering application of an underground water bioremediation technology.

The invention relates to a method for preparing irisflorentin by utilizing belamcandin, and belongs to the technical field of biology. The method comprises the following steps: carrying out C-5 site and C-3'site methylation reaction by taking white belamcandin as a substrate, taking belamcanda methyl transferase gene BcOMT03 gene encoding protein and belamcanda methyl transferase BcOMT33 gene encoding protein as catalysts and taking S-adenosine-methionine as a methyl donor to generate a corresponding glycosylation product. According to the invention, the functions of the two methyltransferase genes BcOMT03 and BcOMT33 in the blackberry lily are identified and verified for the first time, the effect of the two methyltransferase genes BcOMT03 and BcOMT33 in catalyzing the ibullamcandin to produce the irisflorentin is defined, and the blank of research on the biosynthetic pathway of the characteristic component irisflorentin of the blackberry lily is filled up; important information is provided for research on a biosynthesis mechanism of active ingredients of medicinal plants.

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 discloses a recombinant O-acetyl-L-homoserine mercaptotransferase mutant, a recombinant genetically engineered bacterium and application of the recombinant O-acetyl-L-homoserine mercaptotransferase mutant and the recombinant genetically engineered bacterium. The mutant is obtained by performing single mutation or multiple mutation on the 33rd site, the 55th site, the 237th site and the 238th site of an amino acid sequence shown in SEQ ID NO.2. The method has the beneficial effects that the method has more efficient catalytic activity and stronger substrate tolerance, has the advantages of mild conditions, less discharge of three wastes, high selectivity and high product yield when being used for catalyzing OAH and sodium methyl mercaptide to synthesize L-methionine, and has a wide development space in the aspect of industrial production of L-methionine.

The invention relates to the technical field of medicines, in particular to a preparation process of xantinol nicotinate injection and an impurity control method of the xantinol nicotinate injection. According to the process, water for injection is subjected to nitrogen deoxidation treatment, a whole-process nitrogen-sealed environment is maintained, xantinol nicotinate is gradually added in three times, and a multi-component synergistic stable system including hydroxypropyl-beta-cyclodextrin, N-acetyl-L-cysteine, L-methionine, diethylenetriamine pentaacetic acid, sodium metasulfite, sodium thiosulfate and the like is matched, so that the xantinol nicotinate injection is prepared. Double-molecular-weight dextran is introduced to regulate and control a microenvironment, an acetic acid-sodium acetate buffer system is introduced to optimize pH, and finally, high stability and low impurity generation of the finished injection at high temperature are realized through nitrogen replacement subpackaging and precise sterilization conditions. According to the method, the content and the purity of the xantinol nicotinate injection are remarkably improved, the impurity content during sterilization and storage is remarkably reduced, the safety and the effectiveness of drugs are guaranteed, and the method has important significance on optimization of a heat-sensitive injection process.

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 methionine sulfoxide reductase B1 inhibitor and an anticancer composition comprising same. More specifically, the present invention relates to 4-[3-(4-ethylphenyl)-5-(4-hydroxyphenyl) -4,5-dihydro -1 H-pyrazol-1-yl]benzene-1-sulfonamide or 6-chloro-10-(4-ethylphenyl)-4-hydroxypyrimido[4,5-b]quinolin-2(10H)-one, which is a MsrB1 inhibitor, and an anticancer composition comprising same. The MsrB1 inhibitor of the present invention has been confirmed to inhibit differentiation into tumor-friendly M2 macrophages and to suppress tumor growth. In addition, the MsrB1 inhibitor of the present invention was found to exhibit anticancer effects through immune regulation within the tumor microenvironment, and thus can be usefully applied as a composition for cancer treatment.

The invention discloses a guanidinoacetic acid N-methyltransferase mutant and application of the guanidinoacetic acid N-methyltransferase mutant in synthesis of creatine, and belongs to the technical field of bioengineering. The invention provides a method for preparing creatine by utilizing a guanidinoacetic acid N-methyltransferase mutant (Y134I / N170H) and catalyzing guanidinoacetic acid and S-adenosylmethionine in a whole-cell form. The genetically engineered bacterium for expressing the guanidinoacetic acid N-methyltransferase mutant is fermented for 24 hours under the conditions that the whole cell amount is 0.2 g, the pH value is 7.5, the reaction temperature is 37 DEG C, the concentration of guanidinoacetic acid is 80 mM, and the concentration of S-adenosylmethionine is 100 mM, the creatine yield is 7.34 g / L, and the molar yield is 69.96%. According to the method disclosed by the invention, the production cycle is shortened, the yield of creatine is increased, and the industrial process of producing creatine by an enzyme conversion method is accelerated.