Abstract: A transaminase mutant and the use thereof, herein the transaminase mutant has a sequence formed after an amino acid mutation occurs in a sequence as shown in SEQ ID NO: 1, and the site at which the amino acid mutation occurs includes a V242W site. The transaminase obtained has relatively high catalytic activity, specific selectivity, wide substrate spectrum and broad industrial prospect.

Abstract: The present application provides a method for one-pot biosynthesis of arabinonucleoside, and a composition. The method for one-pot biosynthesis of arabinonucleoside includes: mixing a substrate, uracil nucleoside phosphorylase or pyrimidine nucleoside phosphorylase, and purine nucleoside phosphorylase together, then performing biosynthesis, and directly obtaining arabinonucleoside through preparation by means of a one-pot method. The uracil nucleoside phosphorylase includes UP shown in SEQ ID NO: 1; the pyrimidine nucleoside phosphorylase includes PyNP shown in SEQ ID NO: 2; the purine nucleoside phosphorylase includes PNP shown in SEQ ID NO: 3; the substrate includes 1-beta-D-Arabinofuranosyluracil and a substrate base.

Abstract: Provided are an enzyme immobilization carrier and a preparation method therefor, an immobilized enzyme and a preparation method therefor, and use thereof. The enzyme immobilization carrier comprises a resin matrix and a divinyl sulfone group modified on the resin matrix by means of a covalent bond. In order to realize the directed immobilization of an enzyme, the divinyl sulfone group is loaded on the resin matrix by means of the covalent bond. In a subsequent enzyme immobilization reaction, by using specific binding of the divinyl sulfone group to a histidine tag, the divinyl sulfone group in the enzyme immobilization carrier is connected to a specific amino acid residue in an enzyme molecule by means of a covalent bond, without reacting with an active group in the enzyme molecule, thereby effectively avoiding excessive influence of the enzyme immobilization carrier on enzyme conformation, and thus retaining a high catalytic activity of the enzyme.

Abstract: An immobilized 4,5-dicyanoimidazole, and a preparation method and application thereof. The immobilized 4,5-dicyanoimidazole is obtained through a free radical copolymerization reaction of a first comonomer, a second comonomer, and a third comonomer. The first comonomer is divinyl benzene or ethylene glycol dimethacrylate. The second comonomer is styrene or methyl methacrylate.

Abstract: Provided is a method for preparing an oligonucleotide with a ribonucleic acid (RNA) ligase. The RNA ligase includes any one or more enzymes of RNA ligase families Rnll, Rn12, Rn13, and Rn15, and the oligonucleotide includes natural RNA or non-natural RNA. The method may solve the problem that in the prior art, it is difficult to efficiently synthesize a non-natural RNA strand, and the method is suitable for the field of RNA synthesis.

Abstract: Provided are a transaminase mutant and an application thereof. Compared with an amino acid sequence shown in SEQ ID NO:1, an amino acid sequence of the transaminase mutant includes at least one of the following mutation sites: L166, K149, K146, A168, H73, F133, H82, E24, V194, T294, A295, G235 and F236. The mutant of the present invention has the improved catalytic activity for a transammonization reaction of ketone substrates, and is suitable for industrial production of chiral amines.

Abstract: Provided are a cytochrome P450 enzyme mutant and an application thereof. The enzyme activity and anti-Markov oxidation selectivity of P450 derived from a wild-type strain of Bacillus megaterium undergo protein modification by means of directed evolution, thus improving enzyme activity and selectivity, and developing a series of P450 enzyme mutants that may be used for industrial production.

Abstract: Provided are a transaminase mutant and use thereof. The transaminase mutant is obtained by mutation occurred in an amino acid sequence as shown in SEQ ID NO:1, and the mutation includes at least T291A; or an amino acid sequence of the transaminase mutant has the mutation in the mutated amino acid sequence, and has more than 80% of identity with the mutated amino acid sequence, preferably has 85% of identity, and more preferably has 90% of identity.

Abstract: An amino acid sequence of the transaminase mutant is an amino acid sequence obtained by a mutation of an amino acid sequence is shown in SEQ ID NO: 1. The mutation occurred at least one of the following mutation sites: G17V, L36P, Q40H, G69Y, H70T, L73A, V77G, V77S, V77T, A78I, Y130M, Y130V, Y130T, N132I, N132T, K141S, K142S, K142T, R143P, G144F, G144W, G144Y, E145D, E145S, E145G, K146R, L148A, L148I and the like.

Abstract: The present application provides an immobilized enzyme, a preparation method therefor and an application thereof. The immobilized enzyme includes an epoxy resin carrier and an enzyme, the enzyme and the epoxy resin carrier are linked by a covalent bond, and the epoxy resin carrier is an LX-109S epoxy resin. The LX-109S epoxy resin is used as the epoxy resin carrier in the present application, such that on the basis of characteristics of the carrier itself, an immobilization effect of the carrier on the enzyme is more stable, and covalent bonding with the enzyme is firm without affecting the activity of the enzyme itself.

Abstract: Provided are a transaminase mutant and use thereof. The transaminase mutant has an amino acid sequence obtained by mutation of an amino acid sequence shown in SEQ ID NO:1, the mutation at least includes one of the following mutation site combinations: T7C+S47C, Q78C+A330C, V137C+G313C, A217C+Y252C and L295C+C328C; or the transaminase mutant has an amino acid sequence which has the mutation sites in the mutated amino acid sequence and has 80% or more identity with the mutated amino acid sequence. The transaminase mutant realizes the change of protein structure and functions, reduces the enzyme amount, increases the enantiomeric excess (ee) value of a product, and reduces the difficulty of post-processing, so that the transaminase mutant may be suitable for industrial production.

Abstract: The present disclosure discloses a continuous preparation method for a penem intermediate MAP. The continuous preparation method includes the following steps: step S1, in a column-type continuous reactor, using a rhodium-loaded catalyst to catalyze 4-nitrobenzyl(R)-2-diazo-4-((2R,3S)-3-((R)-1-hydroxyethyl)-4-oxoazetidin-2-yl)-3-oxopentanoate to generate a cyclization reaction so as to form a first intermediate, herein the rhodium-loaded catalyst is loaded in the column-type continuous reactor, and the rhodium-loaded catalyst has the following structural formula: step S2, performing an esterification reaction on the first intermediate, a diphenyl chlorophosphate and a diisopropylethylamine in a second continuous reactor, to obtain a product system containing the penem intermediate MAP; and step S3, performing crystallization treatment on the product system, to obtain the penem intermediate MAP.

Abstract: Provided are an enzyme immobilization carrier and a preparation method therefor, and an immobilized enzyme and a preparation method therefor. The enzyme immobilization carrier includes a resin ball matrix, an —N(CH2OOH)2 group linked on the resin ball matrix by means of a chemical bond, and a metal ion adsorbed on the —N(CH2OOH)2 group in a chelating manner through coordination. The resin ball matrix is an amino-type methacrylic resin and/or an epoxy-type methacrylic resin, and the resin ball matrix has a particle size of 200-700 ?m. Therefore, the problems in the related art that an enzyme immobilization carrier is relatively poor in enzyme compatibility and poor in immobilization effect, and an immobilized enzyme is relatively poor in activity, and relatively poor in stability during repeated use are solved.

Abstract: Provided are a catalyst loaded with a TEMPO-type compound, and a preparation method and use thereof. The catalyst loaded with the TEMPO-type compound uses a polymer resin as a carrier, and the polymer resin is a polystyrene resin containing a chloromethyl or bromomethyl, herein the content of the chloromethyl or bromomethyl in the polymer resin is 0.5-5.0 mmol g?1.

Abstract: Provided are an immobilized enzyme and an application thereof in continuous production. The immobilized enzyme is a Polyethyleneimine (PEI)-modified immobilized enzyme, and includes: an enzyme, which includes Amine Dehydrogenase (AmDH) and/or Formate Dehydrogenase (FDH); and a carrier, which is a cyanuric chloride-activated amino carrier. The problem in the prior art of poor performance of an immobilized enzyme is solved, the catalytic activity and reusability of the immobilized enzyme are improved, and the immobilized enzyme is suitable for the field of enzyme immobilization.

Abstract: A method for continuously synthesizing N-Boc-2,5-dihydropyrrole is provided. The method includes the following steps: cis-1,4 dichloro-2 butene is dissolved in an organic solvent, to prepare solution A; urotropine is dissolved in an organic solvent, to prepare solution B; the solution A and solution B are fed into a first continuous reaction device; a product overflow system is transferred to a second continuous reaction device, and concentrated hydrochloric acid is fed into the same; a product overflow system of the second continuous reaction device is transferred to a third continuous reaction device, and potassium carbonate is fed into the same; a product overflow system of the third continuous reaction device is transferred to a fourth continuous reaction device, and Boc acid anhydride solution is fed into the same; and a product of the fourth continuous reaction device is subjected to continuous solid-liquid separation, concentration and distillation, to obtain N-Boc-2,5-dihydropyrrole.

Abstract: The disclosure provides a new crystal form of ertapenem sodium and preparation method therefor. The new crystal form of ertapenem sodium has 27 principal characteristic peaks in an X-ray powder diffraction diagram. The crystal form of ertapenem sodium of the disclosure has a rod-like crystal habit, which has a large particle size, is not prone to aggregation and is easier to dry, and a product with high crystallinity and high purity may be obtained by simple drying treatment. Meanwhile, the crystal form of the disclosure has better stability, and the crystal form may remain unchanged to a maximum extent in subsequent washing and drying processes, thereby further improving the purity of the product.

Abstract: Disclosed are a monooxygenase mutant and use thereof. An amino acid sequence of a monooxygenase mutant is an amino acid sequence obtained by mutating an amino acid sequence as shown in SEQ ID NO: 1. Mutation includes at least one of the following mutation sites: site 49, site 60, site 61, site 144, site 145, site 146, site 147, site 167, site 169, site 189, site 246, site 247, site 280, site 284, site 285, site 286, site 287, site 328, site 330, site 332, site 382, site 427, site 428, site 429, site 430, site 431, site 432, site 433, site 434, site 435, site 436, site 438, site 441, site 493, site 494, site 508, site 509, site 510, site 511, site 512, and site 513 sites and the like.

Abstract: Provided are a transaminase mutant and an application thereof. The transaminase mutant has an amino acid mutation based on a sequence shown in SEQ ID NO: 1, the amino acid mutation being a single position mutation from among W60Y, Y168A, V379W, V379L, V379M, C418Q and C418W or a combination thereof. The activity, stability, and tolerance to temperature, pH and organic solvents of such transaminase mutants are improved. The present application solves the problem of poor tolerance of extreme environments by transaminase in the prior art, and is suitable for the field of enzyme engineering.

Abstract: Provided are a lipase mutant and an application thereof. Specifically, one or more mutations selected from A262H, A338V, V3641, A158PN, and 1159N are generated on the basis of an amino acid sequence as shown in SEQ ID NO: 1; and compared with a parental lipase, a change in the structure and function of a protein occurs in the lipase mutant, and the stereoselectivity is improved, such that a usage amount of an enzyme is decreased to a certain extent, the post-treatment difficulty is reduced, and the lipase mutant is suitable for industrial production.