35 results about "Leucine/Phenylalanine" patented technology

The invention discloses a carboline carboxylic acid-tetrapeptide conjugate and a synthesis method as well as application thereof used as an antithrombotic agent. In the invention, tri-carboxyl of 3S-1,2,3,4-tetrahydro-Beta-carboline-3-carboxylic acid with antithrombotic activity is conjugated with the ammonia end of AA-Tyr-Ser-Val tetrapeptide to obtain a finished product after deprotection, wherein AA is selected from alanine, glycine, proline, glutamine, leucine, phenylalanine, isoleucine, valine, tyrosine, tryptophane, histidine, asparaginate, aspartate, glutamate, serine, threonine, methionine, lysine or arginine residue. The evaluation experiment on a thrombotic model of a rat shows that the compound of the invention has excellent antithrombotic activity and can be applied as the antithrombotic agent. In addition, the invention can overcome the defect of low bioavailability caused by low solubility of the 3S-1,2,3,4-tetrahydro-Beta-carboline-3-carboxylic acid in polar solvents and non-polar solvents.

Compounds that modulate natural β amyloid peptide aggregation are provided. The modulators of the invention comprise a peptide, preferably based on a β amyloid peptide, that is comprised entirely of D-amino acids. Preferably, the peptide comprises 3–5 D-amino acid residues and includes at least two D-amino acid residues independently selected from the group consisting of D-leucine, D-phenylalanine and D-valine. In a particularly preferred embodiment, the peptide is a retro-inverso isomer of a β amyloid peptide, preferably a retro-inverso isomer of Aβ17-21. In certain embodiments, the peptide is modified at the amino-terminus, the carboxy-terminus, or both. Preferred amino-terminal modifying groups include cyclic, heterocyclic, polycyclic and branched alkyl groups. Preferred carboxy-terminal modifying groups include an amide group, an alkyl amide group, an aryl amide group or a hydroxy group. Pharmaceutical compositions comprising the compounds of the invention, and diagnostic and treatment methods for amyloidogenic diseases using the compounds of the invention, are also disclosed.

Compounds that modulate natural β amyloid peptide aggregation are provided. The modulators of the invention comprise a peptide, preferably based on a β amyloid peptide, that is comprised entirely of D-amino acids. Preferably, the peptide comprises 3-5 D-amino acid residues and includes at least two D-amino acid residues independently selected from the group consisting of D-leucine, D-phenylalanine and D-valine. In a particularly preferred embodiment, the peptide is a retro-inverso isomer of a β amyloid peptide, preferably a retro-inverso isomer of Aβ17-21. In certain embodiments, the peptide is modified at the amino-terminus, the carboxy-terminus, or both. Preferred amino-terminal modifying groups alkyl groups. Preferred carboxy-terminal modifying groups include an amide group, an acetate group, an alkyl amide group, an aryl amide group or a hydroxy group. Pharmaceutical compositions comprising the compounds of the invention, and diagnostic and treatment methods for amyloidogenic diseases using the compounds of the invention, are also disclosed.

The invention discloses a method for labeling escherichia coli proteome by using SILAC (Stable Isotope Labeling with Amino Acids in Cell Cultures) and a special culture medium. The invention provides a special culture medium for the SILAC-labeled escherichia coli. The special culture medium comprises inorganic salt, histidine hydrochloride, isoleucine, valine, leucine, phenylalanine, tryptophan, serine, heavy stable isotope labeled lysine, arginine, threonine, tyrosine, methionine, adenine sulfate, uracil, vitamin B1 and glucose; and the inorganic salt is Na2HPO4.12H2O, KH2PO4, NaCl, MgSO4, NH4Cl and CaCl2. Experiments prove that, the special culture medium for the SILAC-labeled escherichia coli, disclosed by the invention, creates a condition for researches of labeling the escherichia coli proteome, preparing a quantitative internal label and highly-precisely quantifying the escherichia coli proteome.

The invention relates to the technical field of food processing, in particular to a microbial fermentation source flavor supplement and a preparation method and application thereof. The flavor supplement provided by the invention is formed by mixing the fermentation product of Staphylococcus and Lactobacillus plantarum, and the fermentation medium of Staphylococcus includes valine, leucine, isoleucine and phenylalanine. During application, the meat product is cured by using the marinating liquid containing the flavor supplement, and the prepared bacon product has the unique rich bacon flavor of the bacon made by the traditional process. The method of the invention has a simple process, is suitable for industrial production, can greatly improve the problem of poor flavor of the bacon products produced by the roasting and dehydration process, and has a good market prospect.

The invention relates to the field of biological medicine, in particular to hepatitis B virus T epitope peptide which can be used for effectively treating hepatitis B and various complications, and cutting off placental infection to a fetus and milk-born infection of hepatitis B virus to a new born child, and is based on DC cells. The amino acid sequence of the T epitope peptide is QLFHLZLIX (glutamine-leucine-phenylalanine-histidine-leucine-Z-leucine-isoleucine-X), wherein X and Z are optional amino acids.

The invention discloses bean germ meal. Every 100g of bean germ meal comprises the following components: 30-40mg of vitamin C, 6.4g of aspartic acid, 1.98g of tyrosine, 1.7g of valine, 1.6g of leucine, 1.5g of phenylalanine, 1.2g of isoleucine, 1.1g of lysine, 2.6g of threonine, 1.7g of arginine, 0.5g of methionine, 2.6g of proline, 2.0g of glutamic acid, 1.2g of alanine, 1.1g of serine, 0.8g of glycine, 0.6g of histidine and 0.5g of cystine. In the germination process of seeds, the protein of the seeds is hydrolyzed into amino acids which are favorable for being absorbed by the human body; and the bean germ meal is rich in vitamins, mineral substances such as potassium, calcium, iron and zinc as well as various amino acids necessary for the human body, so that the bean germ meal has the effects of inhibiting cancer cells, reducing blood fat, preventing and treating cardiovascular diseases, delaying senescence and the like.

Process for production of non-proteinogenic L-amino acids by direct fermentation of a microorganism strain known per se having a deregulated cysteine metabolism in a manner known per se, which comprises adding, during the fermentation, a nucleophilic compound to the fermentation batch in a manner such that this leads to the production of non-proteinogenic L-amino acids by the microorganism strain.

The invention discloses a special culture medium for labeling Mycobacterium smegmatis protein by using SILAC. The medium for SILAC labeling provided by the present invention is composed of inorganic salts, histidine hydrochloride, isoleucine, valine, leucine, phenylalanine, tryptophan, serine, heavy stability Isotope-labeled lysine, heavy stable isotope-labeled arginine, threonine, tyrosine, methionine, adenine sulfate, uracil and glucose; the inorganic salts are ammonium sulfate, sodium citrate, hydrogen phosphate Disodium, potassium dihydrogen phosphate, ferric ammonium citrate, magnesium sulfate, calcium chloride, zinc sulfate, and copper sulfate. Experiments have proved that the medium developed by the present invention for labeling Mycobacterium smegmatis SILAC can efficiently label Mycobacterium smegmatis protein within 10 generations, which is for the preparation of quantitative internal standard and the efficient and accurate quantitative proteome comparison. Research creates the conditions.

The invention discloses an antibacterial and antifouling polymer brush as well as a preparation method and application thereof. The polymer brush is formed by a conjugate of polyethylene glycol and a polypeptide, wherein one end of the polyethylene glycol is fixed on a solid surface; the polypeptide is composed of 3-6 hydrophobic amino acids; the hydrophobic amino acid is selected from leucine one or more of acid, phenylalanine, valine, and isoleucine. The antibacterial and antifouling polymer brush of the present invention combines polypeptide and polyethylene glycol, which not only endows the solid surface with antibacterial performance, but also has obvious antifouling effect. Compared with ordinary antibiotics, the antibacterial and antifouling polymer brush of the present invention does not produce drug resistance while being antibacterial, and is suitable for various solid surfaces, has wide applicability, and has a wide range of applications in biomedical materials. Application prospects.

Non-proteinogenic L-amino acids produced by direct fermentation of a microorganism strain known per se having a deregulated cysteine metabolism in a manner known per se, which comprises adding, during the fermentation, a nucleophilic compound to the fermentation batch in a manner such that this leads to the production of non-proteinogenic L-amino acids by the microorganism strain.

The invention belongs to the technical field of genetic engineering and enzyme engineering, and specifically relates to BmSPI39 mutant and application thereof. BmSPI39 is composed of the 25th to 98th positions in SEQ ID NO.1. The BmSPI39 mutant is the amino acid sequence of BmSPI39, as shown in SEQ ID NO.1, the alanine at the 56th position is mutated to arginine, Lysine, Serine, Threonine, Glutamine, Tyrosine, Methionine, Leucine, Aspartic Acid, Glutamic Acid, Histidine, Cysteine, Valine, Astragalus Paragine, Isoleucine, Phenylalanine, Tryptophan, Proline or Glycine. The BmSPI39 mutants of the present invention all have inhibitory activity on subtilisin and elastase, and when mutated to arginine or lysine, they also obtain trypsin inhibitory activity, and such mutants can be used to prepare trypsin inhibitors , the application prospect is good.

The present invention provides provides a bacterium of the genus Corynebacterium, in particular of the species Corynebacterium glutamicum, having the ability to excrete an L-amino acid selected from proteinogenic L-amino acids and L-ornithine and new measures for the fermentative production of proteinogenic L-amino acids and L-ornithine by such bacteria.