39 results about "Diaminopimelic acid" patented technology

The invention relates to an antibiotic streptomyces, fermentation product of which can inhibit broad spectrum fungus and protozoan, and field experiment can control crop fungus plant disease and root-knot nematode. The antibiotic streptomyces has good effect, no pollution nuisance and no residue. The antifungal agent has extremely low hazardness for the people and good performance and development prospect for medical and agricultural use. The invention is named as SIM001 antibiotic streptomyces which is Streptomyces antibioticus subspecies xi an, and is preserved as patent in the depositary institution appointed by patent office of state intellectual property office; the preservation data is April 14th, 2005, the name of the depositary institution is CGMCC, and the number of preservation is CGMCC No.1349. The whole cell hydrolysate of the antibiotic streptomyces contains L, L-DAP (Diaminopimelic acid) and no characteristic glucide; the cytoderm belongs to I type and glucide type C; one of the main antibacterial materials is polyene macrocyclic ketolide which belongs to the broad spectrum antifungal substance.

The invention provides recombinant escherichia coli and application to synthesis of tetrahydropyrimidine. The recombinant escherichia coli is obtained by knocking out a diaminapimelate decarboxylase lysA gene of escherichia coli E.coli MG1655 and introducing a tetrahydropyrimidine synthetic gene luster ectABC with a nucleotide sequence shown as SEQ ID NO. 1. The nucleotide sequence of the diaminapimelate decarboxylase lysA gene is shown as SEQ ID NO. 2. A thallus subjected to induced expression takes L-sodium aspartate as a substrate and the substrate is biologically converted to prepare the tetrahydropyrimidine. After conversion is carried out for 20 to 30h, the yield of the tetrahydropyrimidine reaches 2.5 to 3.5g / L, and therefore, the recombinant escherichia coli has relatively good industrial application value.

L-lysine can be produced by culturing an Escherichia coli cell in a culture medium, and collecting L-lysine from the culture medium, wherein the Escherichia coli cell is capable of producing L-lysine, is so modified that the activities of one or more enzymes involved in the synthetic pathway of meso-a,e-diaminopimelic acid (e.g., 2,3,4,5-tetrahydropyridine-2,6-dicarboxylate N-succinyltransferase, succinyldiaminopimelate transaminase, succinyldiaminopimelate desuccinylase, diaminopimelate epimerase) are decreased, and has a gene encoding diaminopimelate dehydrogenase introduced therein.

The invention is applicable to the technical field of plant cultivation, and provides an ornamental plant cultivation medium, a bottled ornamental plant and a preparation method of the bottled ornamental plant. A formula of the ornamental plant cultivation medium is as follows: a 1 / 2MS cultivation medium is used as a basic material, meanwhile 1.8-2.3 g / L of agar, 7-9 g / L of phytagel, 48-53 mg / L of diaminopimelic acid, 9.5-10.5 [mu]mol / L of PQQ and 23-26 mg / L of kanamycin are added, and then the pH value of the ornamental plant cultivation medium is adjusted to be 6.5-6.9. The provided cultivation medium can be used for accelerating plant growth, is also relatively firm, is suitable for long-time plant growth, and is particularly suitable for being used as the cultivation medium of the bottled ornamental plant; the plant is relatively vigorous in growth, relatively strong in stability, better in ornamental value and longer in growth cycle.

Process for the production of -lysine by constructing a recombinant microorganism which has a deregulated lysine 2,3-aminomutase gene and at least one deregulated gene selected from the group (i) which consists of aspartokinase, aspartatesemialdehyde dehydrogenase, dihydrodipicolinate synthase, dihydrodipicolinate reductase, tetrahydrodipicolinate succinylase, succinyl-amino-ketopimelate transaminase, succinyl-diamino-pimelate desuccinylase, diaminopimelate epimerase, diaminopimelate dehydrogenase, arginyl-tRNA synthetase, diaminopimelate decarboxylase, pyruvate carboxylase, phosphoenolpyruvate carboxylase, glucose-6-phosphate dehydrogenase, transketolase, transaldolase, 6-phosphogluconolactonase, fructose 1,6-biphosphatase, homoserine dehydrogenase, phophoenolpyruvate carboxykinase, succinyl-CoA synthetase, methylmalonyl-CoA mutase, provided that if aspartokinase is deregulated as gene (i) at least a second gene (i) other than aspartokinase has to be deregulated, and cultivating said microorganism.

Process for the production of -lysine by constructing a recombinant microorganism which has a deregulated lysine 2,3-aminomutase gene and at least one deregulated gene selected from the group (i) which consists of aspartokinase, aspartatesemialdehyde dehydrogenase, dihydrodipicolinate synthase, dihydrodipicolinate reductase, tetrahydrodipicolinate succinylase, succinyl-amino-ketopimelate transaminase, succinyl-diamino-pimelate desuccinylase, diaminopimelate epimerase, diamino-pimelate dehydrogenase, arginyl-tRNA synthetase, diaminopimelate decarboxylase, pyruvate carboxylase, phosphoenolpyruvate carboxylase, glucose-6-phosphate dehydrogenase, transketolase, transaldolase, 6-phosphogluconolactonase, fructose 1,6-biphosphatase, homoserine dehydrogenase, phophoenolpyruvate carboxykinase, succinyl-CoA synthetase, methylmalonyl-CoA mutase, provided that if aspartokinase is deregulated as gene (i) at least a second gene (i) other than aspartokinase has to be deregulated, and cultivating said microorganism.

The invention relates to a Salmonella choleraesuis double-gene-deletion strain free of a resistance marker, Salmonella choleraesuis C7822 (with an accession number of CCTCC NO: M2011402 ). The strain is obtained by carrying out deletion of the asd gene, one of the important nutrition and metabolism genes of Salmonella choleraesuis, on Salmonella choleraesuis C7821 (with an accession number of CCTCC NO: M2010102 ) which has undergone deletion of the crp virulence gene. The gene-deletion strain C7822 loses the capability of synthesizing diaminopimelic acid (DAP), so the strain cannot survive in a DAP negative environment. After plasmids containing the asd gene are transformed into C7822, the asd gene in the plasmids can form a complementary gene with C7822, which enables C7822 to regain the capability of surviving in a DAP negative environment. The double-gene-deletion strain C7822 obtained in the invention has distinct genetic background, strong security and no resistance marker and can stably carry and express exogenous antigens; the double-gene-deletion strain is a good carrying vector and expression strain for exogenous antigens and has a wide application prospect.

The present invention provides a method and composition for the treatment and prevention of an autoimmune disease such a multiple sclerosis which is mediated by autoreactive T cells. The administration of a NOD-1 agonist is shown to mediate an anti-inflammatory immune response. NOD-1 agonists suitable for use in the methods and compositions of the invention include diaminopimelic acid (DAP)-containing muropeptide compounds such as Tri-DAP and M-TriDAP.

The invention discloses meso-diaminopimelic acid dehydrogenase mutants with improved catalytic efficiency, and belongs to the technical field of gene engineering. According to the invention, single-site / double-site mutation is carried out on meso-diaminopimelic acid dehydrogenase shown as SEQ ID NO.2, and mutant enzymes D94A, W123K, D94A / W123K and W148K are successfully expressed and purified in escherichia coli. Enzyme activity measurement finds that the three meso-diaminopimelic acid dehydrogenase mutants have higher catalytic activity than the wild type, for example, the efficiencies of catalyzing phenylpyruvic acid by the mutant enzymes DAPDH-D94A, DAPDH-W123K and DAPDH-D94A / W123K are respectively improved by 3.5 times, 1.5 times and 1.3 times, and the enzyme activity of key enzymes issuccessfully improved.

The invention discloses a metabolic composition for pre-operative early warning of kidney delayed graft function of a donor donated after cardiac death. The metabolic composition is prepared from oneor more selected from seven metabolites including ascorbic acid, diaminopimelic acid, cinnamic acid, isobutyl-isobutyrate, androstenedione, 3-oxocaprylic acid and uroporphyrin. The invention further discloses a screening method of the metabolic composition. In the screened metabolic composition, the binding indication rate of ascorbic acid and diaminopimelic acid is 0.823, and the binding indication rate of cinnamic acid, isobutyl-isobutyrate, androstenedione, 3-oxocaprylic acid and uroporphyrin is 0.98.

The present invention relates to certain heterocyclic compounds of formula (1) that have the ability to inhibit lysine biosynthesis via the diaminopimelate biosynthesis pathway in certain organisms. As a result of this activity these compounds can be used in applications where inhibition of lysine biosynthesis is useful. Applications of this type include the use of the compounds as herbicides.

The ability and speed with which a coryneform bacterium can produce L-lysine are improved when the coryneform bacterium contains an aspartokinase in which feedback inhibition by L-lysine and L-threonine is substantially desensitized. This is accomplished by successively enhancing the DNA coding for dihydrodipicolinate reductase, the DNA coding for dihydrodipicolinate synthase, the DNA coding for diaminopimelate decarboxylase, and the DNA coding for diaminopimelate dehydrogenase.

The invention discloses an identification method of red norcardia cell wall skeleton. The method comprises the following steps: (1) sample spotting: using at least two silica-gel G thin-layer plates, spotting a proper amount of an alanine reference solution and a test sample solution on the first thin-layer plate; then spotting a proper amount of a meso-diaminopimelic acid reference solution and a test sample solution on the second thin-layer plate; (2) development: soaking the first thin-layer plate into a developing solvent composed of n-butanol-glacial acetic acid-water according to a volume ratio of 8:3:1, soaking the second thin-layer plate into a developing solvent composed of sodium dodecyl sulfate-n-butanol-n-hexane-water according to a volume ratio of 6:25:6:20; wherein the distance between the surface of the developing solvent to the bottom edge of the thin layer plate is in a range of 0.5 to 1.0 cm and the sample spots cannot be emerged by the developing solvent; sealing the top cover, when the developing solvent reaches the two thirds of the total length of the thin-layer plate, taking out the thin-layer plate, drying; (3) color developing; (4) observation. The identification method has the advantages of clear color development, high separation degree, and high reliability.

The invention provides a synthetic method of D-heterocyclic amino acid, a kit and an application. The synthetic method comprises the step that a keto acid compound of D-heterocycles is transformed into D-heterocyclic amino acid by diaminopimelic acid dehydrogenase shown as SEQ ID NO:1. The keto acid compound of D-heterocycles is transformed into D-heterocyclic amino acid by diaminopimelic acid dehydrogenase, so that non-natural chiral amino acid with higher transformation rate and higher ee can be obtained, the synthetic method based on diaminopimelic acid dehydrogenase adopts stable technological conditions and mild reaction conditions, the whole production process is simple to operate, less pollution is produced, and one new way of thinking is provided for artificial synthesis of D-heterocyclic amino acid.

This invention relates to an isolated nucleic acid fragment encoding a plant enzyme that catalyze steps in the biosynthesis of lysine, threonine, methionine, cysteine and isoleucine from aspartate, the enzyme a member selected from the group consisting of: dihydrodipicolinate reductase, diaminopimelate epimerase, threonine synthase, threonine deaminase and S-adenosylmethionine synthetase. The invention also relates to the construction of a chimeric gene encoding all or a portion of the enzyme, in sense or antisense orientation, wherein expression of the chimeric gene results in production of altered levels of the enzyme in a transformed host cell.

The present invention provides a method and composition for the treatment and prevention of an autoimmune disease such a multiple sclerosis which is mediated by autoreactive T cells. The administration of a NOD-1 agonist is shown to mediate an anti-inflammatory immune response. NOD-1 agonists suitable for use in the methods and compositions of the invention include diaminopimelic acid (DAP)-containing muropeptide compounds such as Tri-DAP and M-TriDAP.

The document describes biochemical pathways for producing 2- aminopimelate from 2,6-diaminopimelate, and methods for converting 2- aminopimelate to one or more of adipic acid, adipate semialdehyde, caprolactam, 6- aminohexanoic acid, 6-hexanoic acid, hexamethylenediamine, or 1,6-hexanediol by decarboxylating 2-aminopimelate into a six carbon chain aliphatic backbone and enzymatically forming one or two terminal functional groups, comprised of carboxyl, amine or hydroxyl group, in the backbone.

The invention provides a screening method of a medicine for treating citrus huanglongbing. The method comprises the following steps: 1) performing database comparison to obtain a succinyl diaminoheptanedioic acid desuccinylase gene sequence of Asia species of citrus huanglongbing; 2) carrying out mutation on amino acids at the fifth site and the fifteenth site of the succinyl diaminoheptanedioic acid desuccinylase protein sequence of the Asia species of citrus huanglongbing; 3) constructing a dimer protein with two active centers; 4) scoring molecular docking; 5) screening alternative compoundmolecules; 6) preparing a medicament for transfusion of citrus huanglongbing trees; 7) treating the sick trees; 8) taking phloem tissues of diseased branches, and extracting total DNA; and 9) selecting the alternative compound molecules with the most reduced germ concentration as target compound molecules by a PCR method. According to the screening method of the medicine for treating the citrus huanglongbing, the compound capable of treating the plant huanglongbing is obtained by molecular biological analysis and field screening.

The purpose of the present invention is to provide a novel method with which it is possible to quantify diaminopimelic acid-containing bacteria contained in a test sample. The present invention relates to a method for quantifying diaminopimelic acid-containing bacteria contained in a sample to be detected, the method being characterized by comprising: determining the amount of diaminopimelic acid derived from the diaminopimelic acid-containing bacteria in the sample to be detected as an index, and determining the amount of diaminopimelic acid derived from the diaminopimelic acid-containing bacteria in the sample to be detected; and a step for quantifying the bacteria containing diaminopimelic acid.

The invention discloses a serum diaminopimelic acid detection kit based on liquid chromatography-mass spectrometry, a detection method and application, and belongs to the technical field of biological detection. The detection kit comprises an extraction reagent and a derivatization reagent; the extraction reagent comprises a DAP standard substance and a DAP isotope internal standard substance, and the derivatization reagent comprises a borate buffer solution and 6-aminoquinoline-N-succinimide methyl ester (AQC). Through research and development of the kit, the content of DAP in serum / plasma can be relatively rapidly and accurately quantified, and the repeatability is good. And the detection accuracy and stability can be improved by using the isotope internal standard. And the detection sensitivity can be improved by utilizing derivatization.

The present application relates to diaminopimelic acid dehydrogenase mutant and its application in D-phenylglycine synthesis. The present application discloses a diaminopimelic acid dehydrogenase mutant which is obtained by molecular modification of diaminopimelic acid dehydrogenase from Bacillus thermozeamaize, a nucleic acid coding the diaminopimelic acid dehydrogenase mutant, a recombinant expression vector containing the nucleic acid, a recombinant expression transformant containing the recombinant expression vector, and the use of the diaminopimelic acid dehydrogenase mutant in the synthesis of D-phenylglycine from asymmetric reduction of aminated benzoylformic acid. Compared with other D-phenylglycine synthesis methods, the route of the present application is simple, the theoretical yield is high, the atom economy is good, the substrate concentration and the product yield are high, and the optical purity of the product is greater than 99%. Therefore, the present application belongs to an environmentally friendly, high stereoselectivity and green and environmentally friendly biosynthesis method, and has good application prospect in the actual production of D-phenylglycine.

The application discloses a kind of nucleic acid aptamer specifically binding meso-diaminopimelic acid and application thereof, belong to the field of bioengineering and detection technology.The sequence of the nucleic acid aptamer is as shown in SEQ ID NO:2, or variant obtained by the addition, deletion or substitution of one or more bases and has the same binding function, and is obtained by screening by an improved Capture-SELEX method, which introduces progressive counter-screening strategy in screening process, effectively improves the specificity of aptamer.The preferred aptamer 34S (SEQ ID NO:3) provided by the application is verified by isothermal titration calorimetry, and has nanomolar level affinity with meso-diaminopimelic acid (DAP).The aptamer can be used as a core recognition element to construct electrochemical, optical and other types of biosensors, detection kits, rapid detection systems or equipment, to realize rapid, sensitive and specific detection of DAP, and has important application value in the field of bacterial identification, infectious disease identification and the like.

The invention discloses a nucleic acid aptamer specifically combined with meso-diaminopimelic acid and application of the nucleic acid aptamer, and belongs to the technical field of bioengineering and detection. The sequence of the nucleic acid aptamer is shown as SEQ ID NO: 2, or a variant which is obtained by adding, deleting or replacing one or more basic groups on the sequence and has the same binding function, the nucleic acid aptamer is obtained by screening through an improved Capture-SELEX method, a progressive reverse screening strategy is introduced in the screening process, and the specificity of the aptamer is effectively improved. The optimal aptamer 34S (SEQ ID NO: 3) provided by the invention is verified by an isothermal titration calorimetry, and the optimal aptamer 34S (SEQ ID NO: 3) and meso-diaminopimelic acid (DAP) have nano-mole-level affinity. The aptamer can be used as a core recognition element, is used for constructing electrochemical, optical and other types of biosensors, detection kits, rapid detection systems or equipment, realizes rapid, sensitive and specific detection of DAP, and has important application value in the fields of bacterial identification, infectious disease recognition and the like.

The invention discloses a method for preparing high-efficiency maigre feed for livestock and poultry from Chinese herbal medicine. The production process comprises the steps of 1) preparation of mainfeed, 2) detection of main feed harmful substances, 3) crushing of the main feed, 4) screening of the Chinese herbal medicine, 5) extraction and purification of the Chinese herbal medicine, 6) preparation of a Chinese herbal preparation, 7) preparation of premix feed by taking collagen, diaminopimelic acid, microelements, humic acid, amino acid, an acidifying agent, decavitamin, an enzymic preparation and probiotics as additives, wherein the main feed comprises a large amount of raw materials including wheat and bean pulp, the Chinese herbal medicine comprises chuanxiong rhizome, poria cocos and the like, and the high-efficiency maigre feed has the advantages of not containing antibiotics and improving the quality of livestock and poultry products.

The invention discloses tricarboxylic acid cycle-free Escherichia coli chassis bacteria as well as a construction method and application thereof. The preparation method of the Escherichia coli chassis bacteria comprises the following steps: increasing the expression quantity and / or activity of tetrahydropyridine dicarboxylic acid: N-acetyltransferase, N-acetyl diaminopimelic acid deacetylase, N-acetyl diaminopimelic acid aminotransferase, O-acetyl homoserine thiolase and homoserine: O-acetyltransferasein host bacteria (Escherichia coli or mutant Escherichia coli), reducing the expression quantity and / or activity of tetrahydropicolinic acid: N-succinyltransferase and homoserine: O-succinyltransferase in the host bacteria, and obtaining the tricarboxylic acid cycle-free Escherichia coli chassis bacteria. Experiments prove that the Escherichia coli chassis bacteria can reduce the carbon loss rate and improve the capability of synthesizing a target product by taking central metabolic intermediates (such as acetyl coenzyme A, pyruvic acid and alpha-ketoglutaric acid) as precursors. The tricarboxylic acid cycle-free Escherichia coli chassis bacteria and the preparation method have an important application value.

The invention discloses a method for constructing a high-yield epsilon-polylysine engineering strain streptomyces diastatochromogenes asnO-argD through overexpression of an asparagine synthetase gene asnO and an N-succinyl diaminopimelate aminotransferase gene argD, and the high-yield engineering strain is applied to fermentation production of epsilon-polylysine. The invention further discloses a preparation method of the high-yield epsilon-polylysine engineering strain and a preparation method of the high-yield epsilon-polylysine engineering strain. The yield of the epsilon-poly-lysine can reach 55.51 g / L through fed-batch fermentation of a fermentation tank of the high-yield strain S. distaatom romogenes asnO-argD 5L, and the yield of the epsilon-poly-lysine is increased by 96.42% compared with the yield of a chassis strain S. distaatom romogenes 6 #-7; compared with a chassis strain S. diastatochromogenes 6 #-7, the production intensity of the strain disclosed by the invention is improved by 66.40%; the epsilon-polylysine / glucose consumption conversion rate (g / g) is improved by 15.76% compared with that of the chassis strain, and the strain has high industrial application value.

Compositions and methods which modulate LL-diaminopimelate aminotransferase are disclosed. Also provided are compositions and methods for enhancing lysine biosynthesis in a cell.

A bacterium belonging to the genus Escherichia, which is transformed by introducing, into its cells, a DNA coding for a dihydrodipicolinate synthase originating from a bacterium belonging to the genus Escherichia having mutation to desensitize feedback inhibition by L-lysine and a DNA coding for an aspartokinase III originating from a bacterium belonging to the genus Escherichia having mutation to desensitize feedback inhibition by L-lysine; preferably a bacterium belonging to the genus Escherichia in which a dihydrodipicolinate reductase gene and a diaminopimelate dehydrogenase gene originating from Brevibacterium lactofermentum (or a succinyldiaminopimelate transaminase gene and a succinyldiaminopimelate deacylase gene) are further enhanced, is cultivated in an appropriate medium, L-lysine is produced and accumulated in a culture thereof, and L-lysine is collected from the culture.

The invention discloses a microorganism self-induced expression system without a resistance gene marker and a construction method thereof, and belongs to the technical field of genetic engineering, the microorganism self-induced expression system comprises plasmids carrying a quorum sensing system, plasmids carrying an auxotrophication system and a chassis microorganism, the plasmids carrying the quorum sensing system comprise LuxI genes, LuxR genes, a promoter PL, a promoter PLux and pYYDT vectors, and the chassis microorganism comprises a pYYDT vector, a pYYDT vector, a pYYDT vector, a pYYDT vector, a pYYDT vector and a pYYDT vector. A plasmid carrying an auxotroph system comprises a nucleic acid sequence for coding diaminopimelic acid (dap), a PCN promoter and a pYYDT vector, a method and a tool for synthetic biology are utilized to carry out genetic modification on chassis microorganisms, the microorganisms are successfully subjected to genetic modification under the condition that the microorganisms do not depend on antibiotics and inducers, and the yield of the microorganisms is improved. Bacteria growth is carried out in the initial stage of microbial culture, when the bacterial population density reaches a certain degree, function expression is automatically switched, dynamic allocation of resources in bacteria is achieved, green and environment-friendly effects are truly achieved, and the application cost is reduced.

L-lysine is produced by culturing the following Escherichia coli having L-lysine-producing ability in a medium modified to reduce the endogenous One or more enzymes of the racemic α,ε-diaminopimelic acid synthesis pathway, such as 2,3,4,5-tetrahydropyridine-2,6-dicarboxylic acid N-succinyltransferase, The activity of succinyldiaminopimelate transaminase, succinyldiaminopimelate desuccinylase or diaminopimelate epimerase, and a gene encoding diaminopimelate dehydrogenase is introduced therein.