15 results about "Aminoacylation" patented technology

The invention relates to a method for efficiently preparing maytansinol by using heterologous alanyl enzyme. The invention provides a genetically engineered bacterium HGFS10 for efficiently preparing maytansinol by using heterologous alanyl enzyme. The genetically engineered bacterium HGFS10 is used for heterologous expression of D-alanyl enzyme, overexpression of a positive regulatory factor gene asm18, overexpression of a C-4 / 5 epoxidase gene asm11 and overexpression of an amide N-methylase gene asm10. The coding gene of the D-alanyl enzyme is smast C, the nucleotide sequence of the coding gene is as shown in SEQ ID NO. 1, and the amino acid sequence of the coding gene is as shown in SEQ ID NO. 2. The in-vitro catalytic efficiency of the D-alanyl enzyme SmAstC on N-demethyl-4, 5-deepoxymaytansinol is 8 times that of a homologous protein AstC of the D-alanyl enzyme SmAstC, and a good tool enzyme is provided for biological manufacturing of maytansinol. D-alanine is added into the culture medium, a direct acyl donor of the enzyme SmAstC is optimized, and the yield of maytansinol reaches 16.18 mg / L and is increased by 15.7% compared with the yield of maytansinol without adding D-alanine into the culture medium.

The invention relates to aminoacyl-tRNA synthetases that aminoacylate tRNA with 2-Aminoisobutyric acid (Aib), thus enabling the incorporation of the Aib into a growing polypeptide chain during translation, e.g. in eubacterial host cells such as E. coli. For example, but not limited to, the invention relates to new aminoacyl-tRNA synthetases and the uses hereof, as well as a method for producing polypeptides that contain one or more Aib.

The present inventive concept relates to methods of nucleic acid sequencing, and applications and uses of the same. Aspects of the inventive concept include nanopore sequencing on nucleic acids, such as ribonucleic acids (RNAs), including, but not limited to, transfer RNAs (tRNAs). Further aspects include kits for performing the methods, and applications of the methods of the inventive concept as substantively described herein.

A site-specific modified engineered tRNA and its application, wherein the modification is to replace one or more natural unmodified nucleotides selected from the 4th, 9th, 13th, 14th, 17th, 18th, 27th, 28th, 32nd, 34th, 35th, 36th, 37th, 38th, 39th, 49th, 50th, 54th, 55th, 58th, 72nd positions on the tRNA molecule with one or more modified nucleotides. Compared with the unmodified tRNA, the site-specific modified tRNA of the present invention has higher structural stability and / or stronger resistance to nuclease degradation, and the aminoacylation efficiency is not significantly reduced and the immunogenicity is not significantly increased. The modified tRNA can be used to eliminate the premature termination of translation caused by nonsense mutations, and has great application potential in the treatment of genetic diseases and tumors related to nonsense mutations. The modification of engineered tRNA is also of reference significance for tRNA drug development, and can guide the modification design of natural tRNA.

The present inventive concept relates to methods of nucleic acid sequencing, and applications and uses of the same. Aspects of the inventive concept include nanopore sequencing on nucleic acids, such as ribonucleic acids (RNAs), including, but not limited to, transfer RNAs (tRNAs). Further aspects include kits for performing the methods, and applications of the methods of the inventive concept as substantively described herein.

A site-specifically-modified engineered tRNA and the use thereof. Said modification refers to replacement, with one or more modified nucleotides, of one or more native unmodified nucleotides selected from sites 4, 9, 13, 14, 17, 18, 27, 28, 32, 34, 35, 36, 37, 38, 39, 49, 50, 54, 55, 58 and 72 of a tRNA molecule. Compared with unmodified tRNAs, the site-specifically-modified tRNA has higher structural stability and / or higher nuclease degradation resistance, the aminoacylation efficiency thereof is not remarkably reduced, and immunogenicity thereof is not remarkably increased. The modified tRNA can be used for eliminating premature translation terminations caused by nonsense mutations, and thus has great application potentials in treating nonsense mutation-related genetic diseases, tumors, etc. The modification of the engineered tRNA also provides valuable insights for drug development of tRNAs and thus can guide the modification design of native tRNAs.

The present invention provides novel active esters of amino acids for use in aminoacylation of tRNAs with reduced safety and waste risks.SOLUTION: The present invention provides a compound represented by formula (I): or a salt thereof, in particular dichloropyridinylmethyl ester and 2,2,2 - trifluoroethyl ester or a salt thereof.SELECTED DRAWING: None

This invention discloses a serine tRNA synthetase mutant and its applications, belonging to the field of enzyme proteins. This invention utilizes machine learning techniques such as AlphaFold3 to predict SerRS and tRNA... Sec The interaction interface, thereby precisely locating the SerRS that affects tRNA Sec By identifying key amino acid residues and employing a semi-rational mutation strategy, SerRS key sites were targeted and modified to enhance their binding to tRNA. Sec By combining binding affinity and catalytic efficiency, a high tRNA binding affinity and catalytic efficiency were constructed. Sec The SerRS variant with aminoacylation activity improves the supply level of Sec, enabling efficient and high-fidelity expression of selenoproteins, eliminating the mis-incorporation of Ser, and providing a new technical means for the biosynthesis of selenoproteins.

The application discloses a protein lysine valylated pan-antibody and a preparation method and application thereof, relates to the technical field of biology, and discloses a polyclonal antibody, wherein an epitope is a valyl group on an epsilon-amino group of a lysine residue in a protein or polypeptide; the pan-antibody has sequence-independent recognition of the valyl group, and does not cross-react with unmodified lysine residues and methionylated lysine residues; the pan-antibody has sequence-independent recognition characteristics, so that researchers can realize qualitative and quantitative analysis of the modification by using conventional immunological means, and the pan-antibody provides a key material basis for revealing the biological functions of valylated modification in tumorigenesis, metabolic regulation and cardiovascular diseases.

The present invention provides a novel amino acid active ester for use in the aminoacylation of a tRNA, said ester being capable of reducing safety and waste risks. The present invention provides a compound represented by formula (I):or a salt thereof, in particular dichloropyridinyl methyl ester and 2,2,2-trifluoroethyl ester or a salt thereof.

This invention relates to the field of biotechnology, specifically to a method for constructing high-throughput sequencing libraries, a kit, and a method for detecting aminoacylated tsRNA. The method for constructing high-throughput sequencing libraries includes the following steps: (1) first-level enzymatic treatment; (2) second-level chemical treatment; (3) third-level enzymatic repair; (4) library construction. This invention constructs a triple cascade treatment system of "specific enzyme digestion labeling - denaturation deaminoacylation - enzymatic modification and repair", which overcomes the three major technical bottlenecks that have long existed in the sequencing of transport tRNA-derived fragments: "signal missed detection", "full-length truncation" and "confusion of active state".

The present invention provides a novel amino acid active ester for use in the aminoacylation of a tRNA, said ester being capable of reducing safety and waste risks. The present invention provides a compound represented by formula (I): or a salt thereof, in particular dichloropyridinyl methyl ester and 2,2,2-trifluoroethyl ester or a salt thereof.

The invention discloses a seryl tRNA synthetase mutant and application thereof, and belongs to the field of zymoprotein.The seryl tRNA synthetase mutant is characterized in that an interaction interface of SerRS and tRNASec is predicted through machine learning technologies such as AlphaFld3, so that key amino acid residues influencing tRNASec recognition in SerRS are accurately positioned, a semi-rational mutation strategy is adopted, the key sites of SerRS are directionally modified, and the seryl tRNA synthetase mutant is obtained. According to the present invention, the serRS variant with high tRNASec aminoacylation activity is constructed by using the serRS as the template, such that the Sec supply level is improved, the high-efficiency and high-fidelity expression of the selenoprotein is achieved, the false doping of the Ser is completely eradicated, and the new technical means is provided for the biosynthesis of the selenoprotein.

The invention belongs to the field of functional feed additives, and provides a preparation method of liquid fermentation soybean peptide and application of the liquid fermentation soybean peptide in feed. A six-step process of pre-dissolving, directional enzymolysis, gamma-glutamyl, cascade tangential flow filtration and steady-state treatment is adopted. Narrow molecular weight distribution is realized through compounding of neutral endo-protease and exo-aminopeptidase; gamma-glutamyltranspeptidase is introduced to enhance the flavor activity; a target molecular weight segment is accurately enriched through a two-stage membrane; mild enzyme deactivation and sterilization are performed to retain active peptides; the pH is adjusted to 3.5-5.5, so that residual enzyme activity and microbial growth are inhibited, and the shelf life stability of the product is improved. According to the process, highly controllable distribution and functional modification of 60-90% of peptide with the molecular weight of 500-3000Da, 30-70% of gamma-glutamyl peptide and 70-100% of peptide with the molecular weight of less than 1000Da are realized, and the contradiction of low-viscosity processing, mild enzyme deactivation, shelf stability, tangential flow grading flux and pollution resistance under the condition of relatively high solid content is solved; the palatability and the flavor stability of the feed are remarkably improved, and the application value in pig feed is wide.

The invention relates to the technical field of biology, in particular to a novel non-natural nucleotide ribozyme system for catalyzing an aminoacylation reaction between tRNA and amino acid and application of the novel non-natural nucleotide ribozyme system. Ribozyme involved in the novel ribozyme system for catalyzing the aminoacylation reaction between the tRNA and the amino acid is artificially synthesized and is composed of partially modified non-natural nucleotides; the ribozyme has an aminoacyl-tRNA synthetase (aARSs) aminoacylation function, can catalyze esterified natural amino acids, non-natural amino acids and carboxylic acid substrates, and is subjected to an aminoacylation reaction with tRNA, so that the (non) natural amino acids are connected to 3 '-OH of the tRNA. According to the invention, by utilizing the characteristics of more structural diversity and higher stability after RNA is chemically modified, a novel ribozyme structure with high activity and good stability can be expected to be obtained, and the ribozyme structure has the function of aminoacyl-tRNA synthetase (aARSs) and has the capability of catalyzing amino acylation reaction of tRNA with amino acid and non-natural amino acid. Compared with the prior art, the novel ribozyme disclosed by the invention, compared with a previously reported flexible enzyme, can obviously improve the aminoacyl reaction efficiency, is simple to prepare and low in cost, and lays a foundation for improving the efficiency of inserting non-natural amino acid in a next step of in-vitro translation.