115 results about "Aromatic amino acids" patented technology

The invention belongs to the technical field of catalysts, and particularly relates to a general preparation method and application of amino acid intercalated layered hydroxide. According to the catalyst material, the nickel-iron layered hydroxide is optimized through amino acid intercalation, aromatic amino acid is anchored between layers of the nickel-iron layered hydroxide through a one-step hydrothermal method, dissolution of metal ions is inhibited, the catalyst structure is stabilized, an interlayer electronic structure is regulated and controlled, and reaction kinetics is accelerated. According to the invention, the improvement method of the organic-inorganic hybrid catalyst is perfected, and a new thought is provided for the development of the nickel-iron layered hydroxide catalyst.

Provided is a variant of an RNA polymerase, the variant being characterized in that an amino acid corresponding to arginine at position 386 in the amino acid sequence of a wild-type T7 RNA polymerase represented by SEQ ID NO: 1 is substituted with an aromatic amino acid.

The embodiment of the invention provides a recombinant pichia pastoris strain as well as a construction method and application thereof. The construction method comprises the following steps: by taking a pichia pastoris strain as a host strain, constructing a dual-synthesis path of phenylalanine ammonialyase and tyrosine ammonialyase in the host strain to obtain a first engineering strain; removing chorismic acid feedback inhibition of the first engineering strain based on metabolic engineering to obtain a second engineering strain; optimizing an aromatic amino acid synthesis route of the second engineering strain to obtain a third engineering strain; knocking out a branch metabolic pathway of the third engineering strain to obtain a fourth engineering strain; increasing precursor supply of the fourth engineering strain to obtain a recombinant pichia pastoris strain; according to the construction method provided by the embodiment of the invention, the synthesis path of p-coumaric acid can be systematically optimized, the recombinant pichia pastoris strain for efficiently producing p-coumaric acid by taking methanol as a carbon source is constructed, and compared with a host strain, the recombinant pichia pastoris strain has the advantage that the yield of p-coumaric acid is remarkably increased.

The invention belongs to the technical field of metabolic engineering and biological manufacturing, and particularly relates to an engineering bacterium for producing gallic acid (GA) and application of the engineering bacterium in production of gallic acid. According to the method, key metabolic nodes in the gallic acid production process are systematically regulated, for example, the hydroxylase activity is improved, the pyruvic acid flow direction is regulated, the aromatic amino acid precursor supply is improved, and the dynamic balance between the engineering bacterium growth and the gallic acid product synthesis is realized, so that the gallic acid yield and the carbon yield are remarkably improved. Experiments show that the gallic acid yield of the engineering bacteria prepared by the invention reaches 12.5 g / L in a shake flask experiment, and reaches 109.8 g / L in a 3 L fermentation tank; and the carbon yield is increased to 0.64 g / g glucose, which is the highest level reported in the current literature.

The invention discloses a microbial composite flora, a microbial agent and application of the microbial composite flora and the microbial agent, and relates to the technical field of microorganisms and application of the microorganisms. The invention relates to a microbial composite flora, which is characterized in that the microbial composite flora comprises Acinetobacter sichuanensis LHH12, Pseudomonas sichuanensis SJ2-76, beneficial nitroreductase (Diaphorobacter nitroreducens SYY4, and Thauera ammoniaca SJ2-12, and the microbial composite flora comprises Acinetobacter sichuanensis LHH12, Pseudomonas sichuanensis SJ2-76, beneficial nitroreductase (Diaphorobacter nitroreducens SYY4, and Thauera ammoniaca SJ2-12. The microorganisms for constructing the composite flora are separated from the semi-coke wastewater, have better phenol resistance and chemical oxygen demand (COD) degradation capacity, and can be used for purifying high-phenol wastewater, biologically removing nitrogen and phosphorus and degrading COD. Under the condition that the original microbial community composition in the wastewater is not changed, the microbial compound flora can effectively improve the degradation rate of COD (Chemical Oxygen Demand) in the phenol-ammonia wastewater and effectively reduce the treatment cost of high-phenol-ammonia wastewater such as semi-coke and the like through the synergistic effect of the strains, and has great potential in the aspect of promoting the low-carbon green sustainable development of the coal chemical industry.

The application provides a recombinant Pichia pastoris strain and a construction method and application thereof. The construction method comprises the following steps: taking a Pichia pastoris strain as a host strain, constructing a double synthesis pathway of phenylalanine ammonia lyase and tyrosine ammonia lyase in the host strain to obtain a first engineering strain; relieving the branch acid feedback inhibition of the first engineering strain based on metabolic engineering to obtain a second engineering strain; optimizing the aromatic amino acid synthesis pathway of the second engineering strain to obtain a third engineering strain; knocking out the branch metabolic pathway of the third engineering strain to obtain a fourth engineering strain; increasing the precursor supply of the fourth engineering strain to obtain the recombinant Pichia pastoris strain. The construction method can systematically optimize the synthesis path of p-coumaric acid, and the recombinant Pichia pastoris strain for efficiently producing p-coumaric acid with methanol as a carbon source is constructed. Compared with the host strain, the yield of p-coumaric acid of the recombinant Pichia pastoris strain is significantly improved.

The present disclosure provides an engineered microorganism capable of biologically producing aromatic amino acids, wherein the engineered microorganism has reduced production of unwanted byproducts and / or increased yield or conversion rate of aromatic amino acids. Also provided are methods for preparing and of using the engineered microorganism, including a method for producing aromatic amino acids.

The invention relates to the field of gene engineering, and particularly provides a PntB mutant for improving the yield of L-tryptophan, a genetically engineered bacterium containing the mutant as well as a construction method and application of the genetically engineered bacterium, aiming at the problem that NADPH (nicotinamide adenine dinucleotide phosphate) is insufficient in the production process of aromatic amino acid, especially L-tryptophan, pyridine nucleotide transhydrogenase beta subunit mutant PntB (A167T) is obtained through site-specific mutagenesis, and the PntB mutant PntB (A167T) is used for improving the yield of L-tryptophan. According to the present invention, the mutant is constructed, the genetically engineered bacterium containing the mutant is constructed, the genetically engineered bacterium is applied to L-tryptophan fermentation so as to promote the conversion of NADH to generate NADPH, the intracellular NADPH concentration is increased by 4.8 times, the L-tryptophan production ability of the genetically engineered strain BDP2 is increased by 38.8% compared with the initial strain BDX1, the L-tryptophan yield reaches 1.02 g / L, and the efficient synthesis of the L-tryptophan is finally achieved.

The invention discloses an aqueous two-phase system for detecting aromatic amino acid and selective response of the aqueous two-phase system to the aromatic amino acid. An S-DPED / SDS / Na2CO3 aqueous two-phase system (ATPS) is constructed for the first time, the upper phase is composed of S-DPED and SDS, and the lower phase is a Na2CO3 solution. The ATPS constructed by the invention can be used for identifying three aromatic amino acids, namely phenylalanine, tryptophan and tyrosine. By adding three aromatic amino acids into ATPS, it is found that the difference of minimum concentrations (namely critical concentrations) required for converting the ATPS into a single phase is large. In addition, when aliphatic amino acids are added to the ATPS, the system does not become a single phase. When the concentration of the three aromatic amino acids is lower than the critical concentration, the distribution difference of the three aromatic amino acids in the upper and lower phases of ATPS is significant, which indicates that the aqueous two-phase system has selective response to the three aromatic amino acids, and detection and identification of the aromatic amino acids are realized.

The invention provides a heat-stress-resistant laying hen feed and a preparation method thereof. The heat-stress-resistant laying hen feed comprises the following raw materials in parts by weight: 50-60 parts of corn, 10-20 parts of soybean meal, 5-15 parts of wheat bran, 1-5 parts of vegetable oil, 5-12 parts of fish meal, 2-5 parts of beta-alanine, 2-5 parts of activated black bean powder, 2-5 parts of quercitrin, 0.2-0.5 part of multivitamins, 4-8 parts of an electrolyte poising agent and 2-3 parts of compound amino acids. The activated black bean powder is obtained by performing enzymolysis activation on black bean powder by using an aromatic amino acid decarboxylase preparation. The laying hen feed disclosed by the invention can be used for feeding laying hens in a high-temperature environment in summer, and through a unique heat stress resistant formula, the heat stress resistant capacity of the laying hens is remarkably improved, adverse effects caused by heat stress are reduced, meanwhile, the antioxidant capacity and the immune function of the laying hens are enhanced, and the growth performance and the egg laying performance of the laying hens are improved.

Aspects of the disclosure relate to aromatic amino acid ammonia lyases (ALs), phenylalanine ammonia lyases (PALs), and tyrosine ammonia lyase (TALs), including engineered enzymes, and their use in catalyzing chemical reactions.

The present invention relates to a novel ATP synthase variant and a method of producing an L-aromatic amino acid using the same. The ATP synthase variant is obtained by substituting one or more amino acids in the amino acid sequence constituting ATP synthase to change the enzymatic activity of the ATP synthase, and a recombinant microorganism comprising the ATP synthase variant is capable of efficiently producing an L-aromatic amino acid.

Provided is a recombinant adeno-associated viral (rAAV) vector comprising one or two of (a) to (c): (a) a nucleotide sequence encoding aromatic L-amino acid decarboxylase (AADC), (b) a nucleotide sequence encoding glucocerebrosidase (GBA1); and (c) a nucleotide sequence encoding a neurotrophic factor (NTF), such as cerebral dopamine neurotrophic factor (CDNF) or glial cell derived neurotrophic factor (GDNF), for treating neurodegenerative disorders, particularly Parkinson's disease (PD), Multiple system atrophy (MSA), Gaucher's disease (GD), and other proteinopathies. Also provided herein are viral particles comprising the rAAV vector, a pharmaceutical composition comprising the viral particles, and uses thereof.

The invention discloses self-assembled nanoparticles for melanoma targeted imaging and photo-thermal therapy, and aims to solve the problems of poor targeting, low photo-thermal efficiency and poor biocompatibility in the existing method for photo-thermal therapy of melanoma. The invention designs a self-assembled nanoparticle based on specific polypeptide (SA-7), aromatic amino acid (FF) and porphyrin (TPP). The nanoparticles formed by self-assembly can efficiently target melanoma cells, and generate a strong photothermal effect under the irradiation of 638nm laser. Meanwhile, the nanoparticles have good biocompatibility and metabolic performance, and can be used for accurate imaging and treatment of melanoma.

The present invention provides a polypeptide NR6 having a dual function of regulating the activity of DBH and DDC enzymes and its application, belonging to the technical field of functional polypeptides. The present invention provides a polypeptide NR6 for the research of interfering small peptides that can target lipopolysaccharide binding protein and dopamine β-hydroxylase and aromatic L-amino acid decarboxylase, which has not yet been seen, and has the function of promoting the activity of dopamine β-hydroxylase and aromatic L-amino acid decarboxylase, thereby promoting the release of dopamine, norepinephrine, epinephrine, serotonin and melatonin in the body, and has anti-inflammatory, anti-depressant, memory recovery, sleep improvement, mental recovery and other functions. In addition, NR6 and its series of small peptides can penetrate the blood-brain barrier and have the advantages of small molecular weight and high stability, which are conducive to commercial application.

A recombinant polypeptide and a recombinant cell both expressing an aromatic amino acid degrading enzyme, and a use of the recombinant polypeptide and the recombinant cell, relating to the field of biotechnology. The sequence of the aromatic amino acid degrading enzyme XAL derived from Phanerochaete chrysosporium is taken as a starting sequence, a series of XAL mutations that can improve the enzyme activity and stability are found by means of screening and verification of mutation sites, the mutants are introduced into the genetically engineered bacteria, and then degradation activity verification is performed; and it is found that compared with a control strain of a transformed non-mutant enzyme, the constructed recombinant strain has the amino acid degradation activity significantly improved. The present invention further relates to a use of a recombinant XAL polypeptide or a recombinant cell, and a composition of the recombinant XAL polypeptide or the recombinant cell for the treatment and industrial purposes.

The application provides a tea plant gene and a method for regulating theanine accumulation in a tea plant CsSSCD1 The application belongs to the technical field of plant molecular biology. CsSSCD1 The base sequence of the gene is shown as SEQ ID No. 1. The application verifies the negative regulation of the gene by using VIGS technology and transient overexpression technology. In addition, through targeted amino acid metabolome analysis, it is found that CsSSCD1 The expression inhibition weakens the synthesis of tyrosine, the expression of the key enzyme AAAT of aromatic amino acid synthesis is inhibited, the accumulation of glutamic acid is reduced but not significant, and the accumulation of glutamine is significantly reduced, finally the degradation of theanine is blocked and the synthesis is increased. It is firstly proposed that the tyrosine degradation pathway may regulate the accumulation of theanine through metabolic pathway interaction and substrate competition mechanism, and on this basis, the key gene of the pathway is identified and functionally verified CsSSCD1 The gene is negatively correlated with theanine metabolism.

The application discloses an ammonia lyase mutant, a recombinant bacterium and application of the ammonia lyase mutant in preparation of aromatic L-amino acid, and relates to the technical field of bioengineering and enzyme catalysis. Compared with a wild-type ammonia lyase, the ammonia lyase mutant comprises any one of the following mutations: M152A and / or L149G, and the amino acid sequence of the wild-type ammonia lyase is shown as SEQ ID NO. 1. The application provides the ammonia lyase mutant with higher enzyme activity and catalytic efficiency than the wild type, which can catalyze preparation of aromatic L-amino acid with high selectivity, high stability and high conversion rate. The ammonia lyase mutant has high stereoselectivity, avoids tedious chiral separation, and can directly obtain a medical-grade high-purity product. The method for preparing aromatic L-amino acid provided by the application can reduce the cost of materials, does not need a cosolvent and other reagents, simplifies the preparation process of aromatic L-amino acid, and has good industrial application potential.

Immunoglobulin (Ig) binding proteins having one or more domains having highly hydrophobic amino acids with branched side chains (Iso, Leu, Val), or aromatic amino acids (Tyr, Phe, or Trp) corresponding to position 4 or 6 or 8 of the Ig binding protein of SEQ ID NO: 1 or functionally similar proteins are provided. The disclosed proteins have superior properties for highly efficient purification methods for antibodies (immunoglobulins), for example, the proteins have high binding capacity and high chemical stability. Also provided are affinity matrices that include the disclosed Ig binding proteins, uses of these Ig binding proteins and / or affinity matrices for affinity purification of immunoglobulins, and methods for affinity purification using the disclosed Ig binding proteins.

A genetic construct comprises a promoter operably linked to a first coding sequence, which encodes tyrosine hydroxylase (TH), and a second coding sequence, which encodes GTP cyclohydrolase 1 (GCH1), wherein the second coding sequence is 3′ to the first coding sequence, and the first and second coding sequences are part of a single operon. The genetic construct does not encode aromatic amino acid decarboxylase (AADC).

This invention provides the application of Lycium barbarum polysaccharide (LBP) in the preparation of drugs for the prevention or treatment of intestinal flora and metabolic disorders. Research results show that LBP can significantly improve cisplatin-induced intestinal microbiota and metabolic disorders in rats, manifested by a significant reduction in CDDP-induced serum AST and ALT levels, and improvement in the degree of liver tissue lesions. Furthermore, LBP did not exhibit toxicity in rats. LBP enhanced the diversity and richness of the gut microbiota, restored the structure of dominant symbiotic bacteria, inhibited the proliferation of potentially pathogenic bacteria, and promoted the enrichment of functional bacteria related to SCFAs generation. LBP also restored abnormal metabolism in branched-chain amino acid and aromatic amino acid metabolism, one-carbon metabolism, and lipid metabolism. This invention provides a theoretical basis for the application of natural active polysaccharides in the prevention and treatment of intestinal microbiota and metabolic disorders.

The invention belongs to the technical field of Baijiu brewing, and particularly relates to a method for directionally enhancing the flavor of high-temperature yeast for making hard liquor. In order to break through the bottlenecks of single substrate utilization and uncontrollable reaction path in the existing yeast flavor regulation and control technology, the yeast flavor regulation and control method disclosed by the invention comprises the following steps: accurately proportioning pentose, hexose, disaccharide, sulfur-containing amino acid and aromatic amino acid, pretreating, preparing a solution, treating yeast-making raw materials, accurately controlling the temperature in the whole fermentation process, turning over yeast and the like. The Maillard reaction path in the high-temperature yeast preparation process is directionally regulated and controlled. Experiments show that the content of pyrazine and terpene compounds in the high-temperature Daqu can be remarkably increased, the characteristic flavors such as wood fragrance, baking fragrance and scorch fragrance are synchronously enhanced, and a systematic technical scheme is provided for regulating and controlling the flavor quality of Baijiu.

The invention discloses a conductive graphene yarn and a preparation method and application thereof, and belongs to the technical field of conductive fibers. The conductive graphene yarn prepared by the method is obtained by blending and spinning high-dispersion graphene oxide A, polyacrylonitrile and polyvinylpyrrolidone, soaking the mixture in a hydroxylamine hydrochloride solution for the first time, soaking the mixture in high-dispersion graphene oxide B for the second time, and finally soaking the mixture in the hydroxylamine hydrochloride solution for the third time. The high-dispersion graphene oxide A is obtained by adsorbing aromatic amino acid on the surface of graphene oxide through non-covalent interaction such as pi-pi; the high-dispersion graphene oxide B is obtained by adsorbing cinnamyl aldehyde on the surface of graphene oxide through non-covalent interaction such as pi-pi; the prepared conductive graphene yarn is good in conductivity, higher in tensile strength and good in antibacterial property.

The invention provides a gambiered canton gauze imitation method based on a Maillard reaction, and belongs to the technical field of textile manufacturing. The method comprises the following steps: S1, preparing a binary glycosyl cross-linking agent mother solution; s2, preparing and applying a working solution; and S3, sequentially carrying out calendering, baking and washing post-treatment on the fabric. According to the present invention, the food additive sucralose polyaldehyde derivative reacts with the amino group, the hydroxyl group and other polar groups in the protein fabric molecule to prepare the yellowish-brown-to-black fabric, the color of the fabric is similar to the color of the gambiered canton gauze, the natural dye dioscorea cirrhosa does not need to be used, and the quality of the prepared gambiered canton gauze is stable and controllable. According to the invention, by adding the aromatic amino acid, the aromatic amino acid and the polyaldehyde derivative of the sucralose serving as a food additive are subjected to a Maillard reaction similar to that in food, so that the produced gambiered canton gauze fabric has a food fragrance and is relatively high in color fastness.

The invention discloses a method for synthesizing shikimic acid from shikimic acid dehydrogenase of a plant and microorganisms, which uses a shikimic acid synthesis method based on a shikimic acid dehydrogenase gene of the plant, and is characterized by comprising the following steps: S1, obtaining a shikimic acid dehydrogenase gene sequence from the plant; s2, performing codon optimization on the gene; s3, inserting the optimized shikimic acid dehydrogenase gene into an expression vector; s4, transferring the expression vector into escherichia coli engineering bacteria to express shikimic acid dehydrogenase; and S5, synthesizing shikimic acid through an in-vitro catalytic reaction. The screened enzyme has the advantages of few side reactions, no inhibition by high-concentration products and high activity. A recombinant strain for producing shikimic acid is obtained by utilizing the enzyme through a metabolic engineering means. The strain does not use plasmids, has strong genetic stability, does not need additional aromatic amino acids in a fermentation medium, has low production cost, high yield and yield and few metabolic byproducts, and has important industrial application value.

The present invention discloses a method for enhancing the transcription level of amino acid synthesis genes to improve the fermentation level of TG enzyme, which is to obtain a mutant strain with high TG enzyme production by over-expressing genes in the synthesis pathways of endogenous proline, histidine, aromatic amino acids, and arginine using its own promoter in Streptomyces pulmonaria IPIO. The present invention enhances the synthesis of proline, histidine, aromatic amino acids, and arginine synthesis genes by enhancing the transcription level of these amino acids, increases the amino acid supply in the TG enzyme synthesis process, and thereby improves the fermentation level of glutamine transaminase. The fermentation yield of glutamine transaminase of the engineered strains WD15, WD18, WD19, and WD22 obtained by the present invention is 22%, 50%, 48%, and 13% higher than that of the control strain at the laboratory shake flask level, respectively.

This application belongs to the field of biology, and specifically relates to a polypeptide and its applications. This application provides a polypeptide comprising an Alphabody and BDNF linked by a linker. The Alphabody has a structure shown in the general formula HRS1-L1-HRS2-L2-HRS3, wherein each of HRS1, HRS2, and HRS3 is independently an α-helix structure containing 2 to 4 consecutive heptapeptide repeating units, said heptapeptide repeating units being polypeptide fragments represented as "abcdefg" or "defgabc", wherein at least 50% of all a and d positions are occupied by isoleucine residues, and wherein each HRS begins with an aliphatic or aromatic amino acid residue located at the a or d position; L1 and L2 are each independently a linker fragment. The polypeptide of this application can increase the exposure of BDNF in plasma and prolong its half-life.

Disclosed herein is a composition comprising a medium and a heterocyclic compound, for detecting a biomolecule in a sample. More specifically, the composition disclosed herein can be used to detect one or more biomolecules comprising one or more aromatic amino acid residues by producing an amino acid conjugate upon associating with the aromatic amino acid residue of the biomolecule. Also disclosed herein are methods of making and using the composition disclosed herein.

A method for functionalization of an aromatic amino acid or a nucleobase with a fluoroalkyl-containing moiety RF, wherein the aromatic amino acid is reacted in the presence of at least one reductant with at least one hypervalent iodine fluoroalkyl reagent carrying the fluoroalkyl-containing moiety RF is disclosed. Novel hypervalent iodine fluoroalkyl reagents is also disclosed.

This invention discloses a self-assembled nanoparticle for targeted imaging and photothermal therapy of melanoma, aiming to address the problems of poor targeting, low photothermal efficiency, and poor biocompatibility in existing photothermal therapy methods for melanoma. This invention designs a self-assembled nanoparticle based on a specific peptide (SA-7), aromatic amino acid (FF), and porphyrin (TPP). The self-assembled nanoparticle can efficiently target melanoma cells and generate a strong photothermal effect under 638nm laser irradiation. Simultaneously, the nanoparticle exhibits good biocompatibility and metabolic properties, making it suitable for precise imaging and treatment of melanoma.