37 results about "Amino-acid racemase" patented technology

A method of preventing or inhibiting infection by a parasite or virus in vivo comprises administering to a human in need thereof a parasite or virus mitogen in a sub-mitogenic amount sufficient to induce a protective immune response against the parasite or virus in the human.

The present invention relates to an amide hydrolase which is with excellent thermostability and stereoselectively hydrolyzes an α-amino acid amide; a gene encoding the enzyme protein; a novel recombinant vector containing the gene; a transformant containing the recombinant vector; and a process for producing an L-α-amino acid using the transformant.

The invention discloses a method for enzymatically producing DL-tyrosine and a broad-spectrum amino acid racemase and its application. The method for enzymatically producing DL-tyrosine comprises the following steps: S1, constructing a recombinant expression vector pET32a-PH0138, Transform into Escherichia coli BL21(DE3) / pG‑KJE8 to obtain the recombinant engineered bacteria BBAR; S2, ferment the recombinant engineered bacteria BBAR expressing BAR enzyme to obtain wet cells; S3, suspend the wet cells and perform crushing treatment, crush The solution is a crude enzyme solution containing a broad-spectrum amino acid racemase; S4, adding L-tyrosine and PLP to the crude enzyme solution obtained in step S3, stirring and converting, until the specific rotation is 0°, the reaction is terminated, and the obtained DL‑Tyrosine in water. The method has the advantages of low raw material price, high conversion rate, simple post-treatment, high product quality, and is suitable for large-scale industrial production.

A method of producing male or female sterile plants comprising the steps of transforming plant material with a polynucleotide which encodes at least one enzyme which reacts with a non-phytotoxic substance to produce a phytotoxic one, and regenerating the thus transformed material into a plant, wherein the said non-phytotoxic substance is applied to the plant up to the time of male or female gamete formation and / or maturation, so that the non-phytotoxic substance provides for the production of a phytotoxic one which selectively prevents the formation of or otherwise renders the said gametes non-functional, wherein the enzyme is expressed preferentially in either male or female reproductive structures, characterised in that (i) the non-phytotoxic substance is selected from the group consisting of ester derivatives of non-phosphonate herbicides which herbicides are directly phytotoxic to non-green tissue, D-alpha amino acids, peptide derivatives of non-protein D-alpha amino acids, S-enantiomers of aryloxyphenoxypropionates and S-enantiomers of ester derivatives of aryloxyphcnoxypropionatcs and (ii) the enzyme is selected from the group consisting of carboxylesterases, D-amino acid oxidases, D-amino acid dehydrogenases, D-amino acid racemases, 2-arylpropionyl-CoA epimerases, alpha-methylacyl-CoA racemases, thioesterases and acyl-CoA synthetases.

An isoamylase having improved heat resistance and an industrial method for producing maltose from starch.The isoamylase is an isoamylase consisting of the amino acid sequence represented by SEQ ID NO: 1 or an isoamylase resulting from deletion, substitution, or insertion of one to several amino acid residues in the amino acid sequence represented by SEQ ID NO: 1, wherein at least valine at amino acid number 515 and methionine at amino acid number 570 are mutated to other amino acids.

The invention discloses an amino acid racemase and its application in catalyzing the racemization of amino acids, belonging to the field of biotechnology. The amino acid racemase is a polypeptide I having an amino acid sequence as shown in SEQ ID NO.1 or a polypeptide II having at least 70% identity with the amino acid sequence shown in SEQ ID NO.1 and having the function of catalyzing amino acid racemization. Amino acid racemase has racemization activity for various amino acid isomers such as Leu and Met, and is thermostable, so it can be applied to enzyme-catalyzed digestion of L-Leu / D-Leu, L-Met / D-Met Rotation is of great significance for the mutual transformation of amino acid enantiomers.

The present invention relates to a novel thermostable N-acylamino acid racemase (NAAAR) isolated from Deinococcus radiodurans NCHU1003, the coding sequence and the preparation thereof. The present invention also discloses the process for preparing highly optically pure L-amino acids, such as L-homophenylalanine (L-HPA) and the derivatives thereof, from N-protected amino acid by using the novel NAAAR combined with L-N-carbamoylase.

The invention discloses alpha-conus polypeptides and use thereof. The invention provides seven polypeptides: a polypeptide I of which the amino acid sequence is represented by a sequence 7 in a sequence table and in which the last amino acid residue is amidated; a polypeptide II of which the amino acid sequence is represented by a sequence 8 in the sequence table and in which the last amino acid residue is amidated; a polypeptide III of which the amino acid sequence is represented by a sequence 9 in the sequence table and in which the last amino acid residue is amidated; a polypeptide IV of which the amino acid sequence is represented by a sequence 10 in the sequence table and in which the last amino acid residue is amidated; a polypeptide V of which the amino acid sequence is representedby a sequence 11 in the sequence table and in which the last amino acid residue is amidated; a polypeptide vI of which the amino acid sequence is represented by a sequence 12in the sequence table andin which the last amino acid residue is amidated; and a polypeptide VII of which the amino acid sequence is represented by a sequence 13 in the sequence table and in which the last amino acid residueis amidated. The result of activity tests, the seven polypeptides of the general formula (I) have pain relieving effect, alpha-conus polypeptides T-1, T-2, T-3 and T-4 have obvious pain-relieving activity, and the alpha-conus polypeptides T-5, T-6 and T-7 also have obvious pain-relieving effect, and the alpha-conus polypeptides have application values in pain-reliving aspect.