1158 results about "Phenylalanine" patented technology

The invention discloses a ganoderma lucidum culture solution and a culture method thereof. Comprising the following raw materials in parts: 30-40 parts of water, 10-20 parts of corn flour, 1-5 parts of ammonium nitrate, 1-5 parts of monopotassium phosphate, 1-5 parts of potassium sulfate, 1-5 parts of boric acid, 1-5 parts of manganese sulfate, 1-5 parts of zinc sulfate, 1-5 parts of copper sulfate, 1-5 parts of ferric sulfate, 1-5 parts of a short-acting growth regulator, 1-5 parts of amino acid, 1-5 parts of vitamins, 1-5 parts of a seaweed extract, 1-5 parts of honey and 1-5 parts of peaches and oranges. The short-acting growth regulator is prepared from gibberellin, auxin and cytokinin according to the ratio of (2-5): (1-8): (2-9), and the amino acid is prepared by mixing isoleucine, lysine, methionine and phenylalanine according to the ratio of (1-5): (2-8): (4-9): (5-7). The nutrient purity of the culture solution can be greatly increased, the fatality rate is reduced, cell elongation and rooting are promoted, plant metabolism and growth can be greatly promoted, and the quality of ganoderma lucidum is improved.

The invention discloses a formate dehydrogenase mutant and application of the formate dehydrogenase mutant in catalysis of carbon dioxide reduction, the 223 arginine (Arg) of an amino acid sequence of formate dehydrogenase PsFDH48 derived from Paracoccus sp. MKU1 is mutated into proline (Pro) or the 242 proline (Pro) is mutated into phenylalanine (Phe) through a site-specific mutagenesis technology, and the obtained mutants R223P and P242F have higher catalytic activity and can be applied to catalysis of carbon dioxide reduction. The catalyst can catalyze CO2 to generate formic acid more effectively in vitro, and has potential application value in the aspects of efficient activation of CO2 and further conversion of CO2 into other mono-carbon compounds through cascade reaction.

The invention relates to the field of polypeptide compositions, in particular to a polypeptide metal chelate and application thereof in the field of cosmetics, and the polypeptide metal chelate is formed by chelating a polypeptide compound and a metal ion compound. The structure of the polypeptide compound is [gamma-Glu] n-AA, n is greater than or equal to 1, and AA is selected from glycine, alanine, valine, leucine, isoleucine, methionine (methionine), proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, asparaginic acid, glutamic acid, lysine, arginine or histidine; the polypeptide chelated zinc prepared by the invention has remarkable oil control and anti-inflammatory effects, and can be compounded with other raw materials to form cosmetics with oil control and acne removal effects.

The invention provides a method for producing L-phenylalanine, 4-hydroxymandelic acid and / or a PHA material through a one-carbon resource and application of the L-phenylalanine, the 4-hydroxymandelic acid and / or the PHA material. According to the method, a halomonas strain which cannot be directly produced by using a one-carbon resource originally is modified, and a carbon dioxide fixed gene is added, so that recombinant bacteria capable of producing L-phenylalanine and 4-hydroxymandelic acid are constructed, and co-production of extracellular L-phenylalanine, 4-hydroxymandelic acid and other high-added-value compounds and intracellular polyhydroxyalkanoate (PHA) is realized. According to the invention, a more economic, sustainable and high-benefit platform for producing L-phenylalanine, 4-hydroxymandelic acid and PHA is established, and the method plays an important role in further reduction of production cost and improvement of sustainable development.

The invention belongs to the technical field of enzyme engineering, and particularly relates to a P450 peroxygenase mutant and application of the P450 peroxygenase mutant in degradation of phenol environmental pollutants. The mutant is formed by mutating phenylalanine into alanine from the 46th amino acid of P450 peroxygenase with an amino acid sequence as shown in a sequence table SEQ ID NO.1, and the amino acid sequence of the P450 peroxygenase is as shown in a sequence table SEQ ID NO.2. The P450 peroxygenase mutant provided by the invention has the advantages of high catalytic efficiency, high protein expression quantity, low industrial cost and the like. The operation process for degrading the phenol environmental pollutants is simple, the process is mature, the cost is low, harmful impurities are not contained, and the method is non-toxic and environment-friendly.

The invention provides a shikimic acid pathway artificial operon and a construction method and application thereof.According to the artificial operon, shikimic acid pathway related genes are integrated and connected in different modes, a trc promoter and an RBS ribose binding site sequence are optimized, and the artificial operon formed through combination has the advantages of being stable, efficient and wide in applicability; different from a relatively extensive shikimic acid way transformation mode in the past, the operon can obviously improve the accumulation capacity of aromatic amino acid, and when the operon is applied to an L-phenylalanine production strain, the yield of L-phenylalanine reaches 105 g / L, and the saccharic acid conversion rate reaches 26.5%.

The invention provides a preparation method of 3-boron-L-phenylalanine or a derivative of 3-boron-L-phenylalanine. The preparation method provided by the invention comprises the step of preparing 3-boron-L-phenylalanine as shown in a formula (VI) or a derivative thereof by taking a compound as shown in a formula (III) as a raw material. The method has the advantages of mild reaction conditions, short route, high yield, few byproducts and low cost, and does not need an extremely low temperature condition process or complicated purification steps. # imgabs0 #

The invention belongs to the technical field of organic synthesis, and particularly discloses an ammonia aromatic alkene modified near-infrared BODIPY fluorescent probe as well as a preparation method and application thereof.The near-infrared BODIPY fluorescent probe is obtained by adopting 6-(dimethylamino) nicotinic aldehyde to directionally modify the alpha position of BODIPY and constructing an expanded conjugated system through Knoevenagel condensation. Wherein dimethylamino provides a strong electron donating effect, a molecular structure is twisted into a non-planar configuration due to steric hindrance of a pyridine ring, pi-pi accumulation is reduced, and an ACQ effect is inhibited. According to the structural modification strategy, significant red shift of absorption / emission wavelength is realized by expanding a molecular pi-conjugated skeleton, and meanwhile, the stability of the BODIPY core and the quantum yield are effectively enhanced. The probe molecule can specifically recognize the diphenylalanine dipeptide structural unit by utilizing the synergistic coordination effect of the 2-aminopyridine derivative and the BODIPY mother nucleus, so that the selective detection of the Alzheimer's disease biomarker Abeta42 is realized, and a novel optical detection tool is provided for the early molecular diagnosis and targeted therapy of AD (Alzheimer's disease).

The invention discloses a 3 '-phosphoadenosine-5'-phosphoryl sulfate synthetase mutant and an application of the 3 '-phosphoadenosine-5'-phosphoryl sulfate synthetase mutant. Compared with a wild enzyme amino acid sequence as shown in SEQ ID NO.1, the amino acid sequence of the 3 '-adenosine-5'-phosphoryl sulfate synthetase mutant has one or two mutations in the 101 site, the 207 site and the 560 site; preferably, phenylalanine at the 101 site is mutated into tryptophan; cysteine at the 207th site is mutated into glycine; phenylalanine at the 560th site is mutated into tryptophan. The invention also provides a synthesis method and application of the 3 '-adenosine-5'-phosphoryl sulfuric acid. The APS intermediate product inhibition effect of hPAPSS1 is relieved through a point mutation technology, the substrate affinity of hPAPSS1 to ATP is improved, and a mutant enzyme with a high PAPS conversion rate is obtained; and the bifunctional enzyme hPAPSS1 is synthesized by heterologous expression of PAPS in escherichia coli, so that the acquisition of the enzyme is simplified, and the synthesis efficiency of PAPS is improved.

The invention relates to the technical field of bioactive peptides, in particular to a novel multifunctional collagen-like tripeptide and application thereof, an amino acid sequence contains multiple combinations, X can be selected from multiple components, 3-methoxy-4-hydroxyphenylalanine and the like are added, and the novel multifunctional collagen-like tripeptide can interact with specific proteins, activate related pathways and play multiple physiological functions and is applied to multiple fields. The collagen-like tripeptide has obvious advantages, innovates component expansion functions, improves the preparation method, improves the efficiency, reduces the cost, is matched with other components in the fields of beauty, health care and medicine, enhances the efficacy, realizes targeted delivery, and brings a new opportunity to related industries.

The invention relates to the field of biological engineering and technology, in particular to an enzyme for synthesizing glabridin, a biological synthesis method of glabridin and a bacterial strain. The invention discloses a series of glabridin synthesizing enzymes (phenylalanine ammonialyase, cinnamic acid-4-hydrogenase, tyrosine ammonialyase, p-coumaric acid coenzyme A ligase, chalcone synthase, chalcone reductase, chalcone isomerase, isoflavone synthase, 2-hydroxyisoflavone dehydratase, 4 '-oxymethyltransferase, 4'-hydroxymethyltransferase and 4 '-hydroxymethyltransferase) derived from glycyrrhiza glabra for the first time. ) can be used in the preparation of a compound (e.g., isoflavone 2 '-hydrogenase, isoflavone reductase, Vissisoketoreductase, isoprenyltransferase, pterocarpin reductase, oxidative cyclase, demethylase, cytochrome P450 reductase, and the like). The de novo synthesis of the glabridin in a microbial cell factory is realized for the first time, and the application prospect of the glabridin biological manufacturing industry is greatly promoted.

The invention discloses a delayed coagulation type polycarboxylate superplasticizer and a preparation method thereof, and relates to the field of concrete admixtures. The retarding type polycarboxylic acid water reducing agent is prepared from 45 to 55 parts of unsaturated polyether monomer, 15 to 20 parts of quaternary ammonium salt cationic monomer, 10 to 15 parts of unsaturated sulfonic acid or unsaturated sulfonate monomer, 5.5 to 7.5 parts of unsaturated phosphate monomer, 4.8 to 6.2 parts of unsaturated hydroxy fatty acid ester monomer, 100 to 120 parts of acrylic acid, 1 to 2 parts of chain transfer agent, 1.5 to 2 parts of oxidizing agent, 0.75 to 1 part of reducing agent and 500 parts of water. The structural general formula of the unsaturated polyether monomer is R1CH2O (CH2CH2O) nR2, R1 is an alkenyl group, and R2 is any one of a phenyl group and a phenylalanine alkyl ester group. The delayed coagulation type polycarboxylate superplasticizer can effectively improve the delayed coagulation effect of a concrete mixture with the fine aggregate mud content larger than 1.5% in a high-temperature environment, and constructability is ensured.

The present invention belongs to the technical field of biological prevention and treatment for viral diseases. Disclosed in the present invention are a tomato disease-resistant gene mutant, and the use thereof in the prevention and treatment of ToBRFV. It is found in the present invention that mutating the nucleotide at position 1927 of the coding region sequence of tomato Tm-22 gene from G to A, or mutating the amino acid at position 643 of the LRR domain of a protein that is encoded by tomato Tm-22 gene from glycine to arginine can remarkably reduce the accumulation level of ToBRFV capsid protein (CP). The gene (named Tm-22-Mut5) can serve as a novel ToBRFV resistant gene, and also retains the resistance to TMV, ToMV and ToMMV. The Tm-22-Mut5 and a pre-screened Tm-22-Mut3-1 mutant (tyrosine at position 767 of the LRR domain thereof is mutated to phenylalanine) undergo combinatorial mutagenesis to obtain a mutant Tm-22-Mut6. Analysis shows that the Tm-22-Mut6 can remarkably reduce the accumulation level of the ToBRFV capsid protein. Compared with the pFGCTm-22-Mut3-1 mutant obtained by screening in the previous research and the newly obtained mutant Tm-22-Mut5, the Tm-22-Mut6 has further improved resistance to ToBRFV.

The invention discloses a p-nitrophenyl ethyl esterase mutant with high enantioselectivity as well as a construction method and application of the p-nitrophenyl ethyl esterase mutant. The p-nitrophenyl ethyl esterase mutant is obtained by mutating an amino acid sequence of wild p-nitrophenyl ethyl esterase pnbA as shown in SEQ ID NO.1 according to one or a combination of more of the following modes: leucine at the 273rd site is mutated into aspartic acid, phenylalanine at the 314th site is mutated into histidine, and leucine at the 362nd site is mutated into arginine. The mutant pnbA-L273D / F314H / L362R provided by the invention shows optimal catalytic performance (E = 47.16) for racemization-acetic acid pinyl hydrate, the enantiomeric excess value of the mutant is 95.13%, the conversion rate of 1S, 5R-acetic acid pinyl hydrate is 90.42%, the enantioselectivity of the mutant is obviously higher than that of a wild type, and the mutant has great application potential in biological catalytic synthesis of monocyclic monoterpenoid chiral alcohols.

A boron carrying agent, a preparation method therefor, and a pharmaceutical formulation. The boron carrying agent contains compound 1, N-4-carboxyphenylboronic acid amide-threonine-phenylalanine-phenylalanine-tyrosine-glycine-glycine-serine-arginine-glycine-lysine-arginine-aspartic acid-aspartic acid-phenylalanine-lysine-threonine-glutamic acid-glutamic acid-tyrosine-cysteine, having a molecular formula of C114H158BN30O35S1 and a molecular weight of 2552.4, and further contains compound 2, N-4-carboxyphenylboronic acid amide-arginine-lysine-lysine-lysine-arginine-arginine-glutamine-arginine-arginine-arginine, and / or compound 3, N-4-carboxyphenylboronic acid amide-methionine-alanine-serine-methionine-threonine-glycine-glycine-glutamine-glutamine-methionine-glycine. Compounds 1-3 can serve as a targeted medicament for boron neutron capture therapy used for treating a cerebral glioma and a head and neck tumor.

The invention belongs to the technical field of microorganisms, and discloses a Lactobacillus paracasei B20 for inhibiting melanin from a plateau area and application of the Lactobacillus paracasei B20, the Lactobacillus paracasei B20 is preserved in the China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC No.32434, and the preservation date is October 31, 2024. Metabolite of the lactobacillus paracasei B20 comprises phenylalanine, p-hydroxycinnamic acid and the like, has strong tyrosinase inhibition effect and anti-ultraviolet ability, and can significantly reduce generation of melanin in skin. In addition, the lactobacillus paracasei B20 also has relatively strong oxidation resistance, has good tolerance in artificial gastric juice and artificial intestinal juice, and can smoothly reach the intestinal tract of a human body. In addition, the lactobacillus paracasei B20 has a relatively obvious growth inhibition effect on skin conditioned pathogens such as staphylococcus aureus and enterococcus faecalis.

The invention discloses a pichia pastoris engineering bacterium for synthesizing bakuchiol from de novo by converting methanol as well as construction and application of the pichia pastoris engineering bacterium. A heterologous p-coumaric acid synthesis pathway is introduced to neutral sites of different chromosomes of pichia pastoris, a high-yield p-coumaric acid strain is obtained through gene knockout, overexpression or heterologous expression of tyrosine and phenylalanine synthesis pathway key genes of a shikimic acid pathway, a heterologous bakuchiol biosynthesis pathway is introduced on the basis, and a high-yield p-coumaric acid strain is obtained. After overexpression of bakuchiol synthetase, endogenous overexpression or heterologous expression of MVA pathway key genes and exogenous acetyl coenzyme A supply pathway genes, methanol concentration optimization and bacterial strain His4 gene supplementation, the yield of bakuchiol is effectively increased to 91.2 mg / L and is increased by 59.8 times compared with that of an initial bacterial strain, and the yield of bakuchiol in a 15L fermentation tank reaches 692.8 mg / L. The method has the characteristics of high conversion efficiency, low production cost, convenience in preparation, wide industrial application prospect and the like.

The invention relates to a recombinant thallus, a construction method of the recombinant thallus and application of the recombinant thallus in production of xanthoxylin WGX-50, and relates to the technical field of bioengineering. A recombinant plasmid containing a phenylalanine ammonialyase gene PAL with a nucleotide sequence as shown in SEQ ID NO.2 and a cinnamic acid coenzyme A ligase gene CNL with a nucleotide sequence as shown in SEQ ID NO.1 and a recombinant plasmid containing a tyramine N-hydroxycinnamoyl transferase gene THT with a nucleotide sequence as shown in SEQ ID NO.3 are introduced into the recombinant plasmid. A phenylalanine ammonialyase gene PAL, a cinnamic acid coenzyme A ligase gene CNL and a tyramine N-hydroxycinnamoyl transferase gene THT are overexpressed in escherichia coli, so that a biological synthesis path of xanthoxylin WGX-50 is formed by taking 3, 4-dioxomethyl phenylethylamine as a substrate for the first time, a foundation is laid for large-scale industrial production, and the method has a wide application prospect. The method has important economic value and social benefit.

The invention provides a preparation method of Keemun camellia seed fermented oil, and belongs to the technical field of vegetable oil production. The preparation method comprises the following steps: S1, preparing recombinant saccharomycetes; s2, jointly fermenting the antarctic torulopsis, the recombinant saccharomycetes and the Keemun camellia seed oil; s3, separating an oil phase from a water phase, and taking the oil phase; and S4, dehydrating the oil phase to obtain the Keemun camellia seed fermented oil. Preferably, according to the preparation method of the recombinant saccharomycetes in the step S1, phenylalanine deaminase, cinnamate hydroxylase, 4-coumaric acid CoA ligase, chalcone synthetase, chalcone reductase and peroxidase are expressed in saccharomyces cerevisiae. According to the Keemun camellia seed fermented oil prepared by the method disclosed by the invention, the characteristic components of the Keemun camellia seed oil can be remarkably improved, the antioxidant capacity of the Keemun camellia seed oil is enhanced while the skin feeling of the Keemun camellia seed oil is improved, and the application value of the Keemun camellia seed oil in cosmetics is improved.

The invention discloses a preparation method and application of a QS-21-polyamino acid nano vaccine, and belongs to the field of biomedical nano materials. The preparation method comprises the following steps: modifying gamma-PGA with phenylalanine ethyl ester (F) to obtain a polymer PF40 of which the F grafting rate is 40%; aiming at the characteristic that QS-21 is strongly combined with cholesterol, PF40 (PFC) grafted with cholesterol (C) is developed, and PFC wraps OVA and QS-21 through hydrophobic force to construct a nano vaccine OQPFC. The cholesterol on the PFC can reduce the combination of the QS-21 and the cholesterol on a cell membrane so as to reduce the biotoxicity of the QS-21, and the QS-21 loading efficiency of the nano vaccine is improved, so that a better treatment effect is achieved. The OQPFC can escape from lysosome through carboxyl protonation, and a large amount of QS-21 and OVA are released in cytoplasm, so that the synergistic cellular immune activation effect of the carrier adjuvant PFC and the saponin adjuvant QS-21 is realized.

The invention discloses a rheumatoid arthritis diagnosis product and system and application thereof, and relates to the technical field of rheumatoid arthritis. The diagnostic marker comprises calcium, a ratio of arginine to ornithine, a ratio of phenylalanine to tyrosine, an anti-cyclic citrullinated peptide antibody and lysine. The invention provides a biomarker capable of accurately diagnosing rheumatoid arthritis RA, which comprises five indexes, namely calcium, the proportion of arginine to ornithine, the proportion of phenylalanine to tyrosine, an anti-cyclic citrullinated peptide antibody (anti-CCP) and lysine. The five indexes have the technical advantages of few indexes and excellent diagnosis performance. A diagnosis model constructed based on the five indexes has good sensitivity, specificity and accuracy. The kit can be used for diagnosis of rheumatoid arthritis.

The invention belongs to the technical field of bioengineering, and relates to a transaminase mutant, a recombinant genetically engineered bacterium and application of the transaminase mutant in catalytic synthesis of (R)-1-Boc-3-aminopiperidine.The transaminase mutant is obtained by conducting single-point or combined mutation on the 131 site and / or the 197 site of an amino acid sequence shown in SEQ ID NO.2; the mutation sites comprise that the 131 phenylalanine is mutated into aspartic acid, threonine or tyrosine, and / or the 197 lysine is mutated into arginine or leucine. Experimental results show that compared with wild type transaminase, the catalytic activity, the thermal stability and the organic solvent tolerance of the obtained mutants, especially single-point mutants MyTA1-F131Y and MyTA1-K197R and a combined mutant MyTA1-F131Y-K197R, are all remarkably improved, and compared with the wild type transaminase, the catalytic activity, the thermal stability and the organic solvent tolerance of the obtained mutants are all remarkably improved. The mutant MyTA1-F131Y-K197R can be used for efficiently catalyzing asymmetric amination of N-Boc-3-piperidone to synthesize (R)-1-Boc-3-aminopiperidine, the conversion rate of the (R)-1-Boc-3-aminopiperidine after the (R)-1-Boc-3-aminopiperidine reacts for 24 hours under the condition that the substrate concentration is 100 g / L can reach 90% or above, and the mutant MyTA1-F131Y-K197R has a good industrial application prospect.

The invention belongs to the technical field of adhesives, and particularly relates to a hot-melt pressure-sensitive adhesive and a preparation method thereof.The hot-melt pressure-sensitive adhesive is prepared from, by weight, 100 parts of modified styrene-butadiene-styrene block copolymer, 10-20 parts of rosin pentaerythritol ester, 15-20 parts of polybutylene, 0.5-1 part of antioxidant, 1-5 parts of flexibilizer and 0.5-2 parts of filler; wherein the flexibilizer is prepared from 10-20 parts of lactic acid, 1-5 parts of phenylalanine and 5-8 parts of epoxidized soybean oil through a copolymerization reaction. According to the invention, the styrene-butadiene-styrene block copolymer is modified by lactic acid, the epoxidized soybean oil is activated and modified by lactic acid and phenylalanine, and a winding system is formed through the cooperation of the modified styrene-butadiene-styrene block copolymer, the flexibilizer, pentalyn and polybutylene; and finally, forming a uniform system with the antioxidant and the filler, thereby enhancing the toughness and permanent adhesion of the hot-melt pressure-sensitive adhesive.

The invention discloses a liquid fertilizer for improving the yield of tuber and bulbil of pinellia ternate and a preparation method thereof, and belongs to the technical field of liquid fertilizers, the liquid fertilizer comprises the following components by concentration: 10-15 mmol / L of phenylalanine, 20-30 g / L of wood vinegar, 8-10 g / L of algin, 5-10 g / L of potassium humate, 0.5-1 g / L of boric acid, 8-12 g / L of a retention agent and 2-8 g / L of a suspension stabilizer; phenylalanine can promote separation and elongation of plant cells so as to adjust the growth and development process of crops. Under the condition of phenylalanine with the concentration of 10-15 mmol / L, the pinellia ternate shows obvious agronomic character advantages, the forms of tubers and bulbils are improved, the weight is increased, the pinellia ternate is fuller, the speed of developing the bulbils into filial generation pinellia ternate can be increased, the yield of the pinellia ternate is increased, and the market competitiveness and the economic benefit are enhanced.

The invention relates to a mutant based on cytochrome P450BM3 and application of the mutant in chloroaniline biodegradation, and belongs to the field of enzymology. The mutant is obtained by mutating threonine at the 268 site of an amino acid sequence shown in SEQ ID NO.1 into aspartic acid or glutamic acid, mutating alanine at the 328 site into phenylalanine, and mutating alanine at the 328 site into phenylalanine. According to the present invention, the amino acid at the 87 site is mutated into alanine, and the valine at the 78 site is mutated into alanine, such that a variety of mutants such as T268D / A328F, T268E / A328F, T268D / A328F / F87A, T268E / A328F / F87A, T268D / A328F / F87A / V78A and T268E / A328F / F87A / V78A are obtained; according to the present invention, the degradation rate of the mutant on 4-chloroaniline, 2-chloroaniline, 2, 4-dichloroaniline, 3, 4-dichloroaniline and 3, 5-dichloroaniline is achieved; the method has important significance and application value for promoting rapid degradation of chloroaniline pollutants in a water environment and maintaining ecological balance.

The invention provides a method for detecting free amino acids in camellia oleosa seed oil, and establishes a method for detecting the free amino acids in the camellia oleosa seed oil based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS / MS), which comprises the following steps: pre-treating various amino acids in the camellia oleosa seed oil by using a non-derivation method; the problems of complicated operation, impurity interference and the like caused by derivatization are avoided, the extraction solvent is environment-friendly and economical, the extraction efficiency is high, and the pretreatment time is greatly shortened; then selecting a proper chromatographic column and a mobile phase, separating a plurality of free amino acids under the condition of not introducing excessive derivatization agents and ion pair reagents, and controlling the collection time to be 12 minutes. The method for detecting the free amino acids in the camellia oleosa seed oil has the characteristics of no need of derivatization treatment, simplicity and convenience in operation, high detection efficiency and good sensitivity and accuracy, and can effectively separate and detect 14 free amino acids such as alanine, phenylalanine and aspartic acid in the camellia oleosa seed oil.

The invention discloses a gelator and a preparation method and application thereof, the structural formula of the gelator is # imgabs0 #, R1 is a side chain group connected to an amino acid central carbon atom except an amino group, a carboxyl group and a hydrogen atom; the amino acid is selected from one of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine and pyrrole lysine; the amino acid is selected from one of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine and pyrrole lysine; r2 is alkyl with the carbon atom number of 16 to 19; and R3 is 9-fluorenyl methoxy carbonyl group or t-butyloxycarbonyl group. The gelator has a hydrophobic long alkyl tail chain, can spontaneously gather and assemble into a three-dimensional network structure through hydrogen bonds, pi-pi interaction and hydrophobic force, and fixes an oil phase in an oil solvent or an oil-water mixture in an effective manner to form high-strength gel.

The invention discloses a portable phenylalanine detector and a use method thereof, and belongs to the technical field of phenylalanine detection equipment.The portable phenylalanine detector comprises a liquid chromatograph body, the liquid chromatograph body comprises a plurality of detection units, the upper side wall of the detection unit on the uppermost side is fixedly connected with a pressure pump, and the upper side wall of the detection unit on the uppermost side is fixedly connected with a pressure sensor; the water outlet end of the pressure pump is fixedly connected with a liquid inlet pipe communicated with the uppermost detection unit, the upper side wall of the uppermost detection unit is fixedly connected with a storage box, the storage box is divided into a water storage area and a sample area, and cleaning water and a sample storage bottle are arranged in the water storage area and the sample area respectively. A conveying pipe is fixedly connected between every two adjacent detection units, and a liquid discharging pipe is fixedly connected to the detection unit on the lowermost side. And through the one-by-one detection assembly, the worker is helped to quickly deduce which section of pipeline and the adjacent detection unit are blocked.

The invention provides a penicillin G acylase AxPGA mutant, an expression plasmid, a genetically engineered bacterium and application, and belongs to the technical field of biocatalysts. The mutant is obtained by mutation of any one or more of the following sites of an amino acid sequence as shown in SEQ ID NO: 1: (1) methionine at the 103rd site is substituted by cysteine, (2) tyrosine at the 424th site is substituted by phenylalanine, (3) tyrosine at the 442nd site is substituted by phenylalanine, and (4) tyrosine at the 451st site is substituted by alanine. The obtained penicillin G acylase AxPGA mutant is relatively high in enzyme activity and can be applied to high-conversion-rate and high-yield synthesis of beta-lactam antibiotics such as benicillin and amoxicillin.

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