272 results about "Isomerase" patented technology

The invention discloses an inositol dehydrogenase mutant and a preparation method of D-chiral inositol, and belongs to the technical field of genetic engineering. The inositol dehydrogenase mutant is obtained by mutating an amino acid sequence as shown in SEQ ID NO.2 through the following mutations: the 200th amino acid is mutated into C from V, the 234th amino acid is mutated into Q from V, and the 256th amino acid is mutated into E from R. According to the invention, the amino acid sequence of wild type inositol dehydrogenase is mutated to obtain the inositol dehydrogenase mutant which is a high-activity mutant capable of catalyzing conversion of myo-inositol into 2-keto-myo-inositol; therefore, when the inositol dehydrogenase mutant and keto isomerase act together to prepare D-chiral inositol by taking myo-inositol as a substrate, the yield of the D-chiral inositol is effectively improved.

The invention discloses L-arabinose isomerase, engineering bacteria and application, the amino acid sequence of the L-arabinose isomerase is shown as SEQ ID NO: 3, and the gene sequence for coding the L-arabinose isomerase is shown as SEQ ID NO: 2. On the basis of a genome of a Peribacillussp.S4 strain, a gene for coding the L-arabinose isomerase is excavated, and a stable prokaryotic expression system is constructed by performing codon optimization on the gene, so that the large-scale controllable production of the L-arabinose isomerase is realized, the yield of the enzyme is remarkably increased, the production cost of the enzyme is reduced, and the method is suitable for industrial production. A stable and economical enzyme source is provided for the production of D-tagatose; the L-arabinose isomerase expressed by the constructed engineering bacteria can significantly improve the yield of D-tagatose, and industrialization of D-tagatose is facilitated.

The invention discloses L-rhamnose isomerase and application thereof, and belongs to the technical field of genetic engineering. The amino acid sequence of the L-rhamnose isomerase is obtained by performing the following mutation on an amino acid sequence as shown in SEQ ID NO.1: the 258th amino acid is mutated from D to Q. Compared with the prior art, the L-rhamnose isomerase mutant D258Q is obtained by mutating wild type L-rhamnose isomerase, and compared with the wild type L-rhamnose isomerase, the L-rhamnose isomerase mutant D258Q is higher in enzyme activity and longer in half-life period, so that when the L-rhamnose isomerase mutant D258Q is used for catalyzing the conversion of D-psicose into D-allose, the L-rhamnose isomerase mutant D258Q has the advantages that the enzyme activity is higher, and the half-life period is longer; the catalytic capability is stronger and more durable, and the conversion efficiency of the reaction and the yield of D-allose are improved.

The disclosure provides method of treating cancer in a patient in need thereof, comprising safely and efficaciously administering to the patient PLX038, a long lasting-PEGylated prodrug of the topoisomerase I inhibitor. The disclosure further provides combination therapies of PLX038 with inhibitors of the DNA damage response (DDR).

The application belongs to the technical field of genetic engineering, and discloses a kind of saccharomyces cerevisiae for producing rare ginsenoside by seaweed biomass and a construction method and application thereof.The saccharomyces cerevisiae has the following characteristics: overexpression of agarase, neojuncanohydrolase, hydroxymethylglutaryl coenzyme A reductase, isopentenyl diphosphate delta isomerase, dammaradienol synthase, protopanaxadiol synthase, cytochrome P450 reductase, protopanaxatriol synthase and glycosyltransferase.The application combines enzymolysis of seaweed biomass with fermentation of rare ginsenoside, which not only endows wild-type yeast with the ability to degrade seaweed biomass that it originally does not have, but also effectively improves the yield of squalene and downstream terpenes (rare ginsenoside Rh1) by overexpression of tHMG1 and IDI1.The saccharomyces cerevisiae can effectively utilize seaweed biomass to obtain squalene and rare ginsenoside Rh1, and has the characteristics of simplicity, economy and ecological friendliness, can convert cheap biomass into high-value products, and provides a way for the development of marine bioeconomy.

The application provides a recombinant Aspergillus niger with high trans-aconitic acid yield and a construction method and application thereof, and relates to the technical field of genetic engineering. Specifically, the recombinant Aspergillus niger heterogeneously expresses aconitate isomerase TbrA and / or Adi1. The application provides a new engineering strain for efficient production of trans-aconitic acid, solves the source predicament of needing plant extraction or needing chemical synthesis in traditional production of trans-aconitic acid, and greatly improves the yield of trans-aconitic acid.

Described is an antibody-drug conjugate (ADC) having the formula A-L, wherein A is an antibody or an antibody fragment and wherein L is a linker, said linker comprising: as a first payload a topoisomerase I inhibitor which is cell-permeable, e.g., a camptothecin cytotoxic molecule which is cell-permeable; as a second payload a topoisomerase I inhibitor which is not cell-permeable, e..g., a camptothecin cytotoxic molecule which is not cell-permeable; and as a as a third payload a toxin or a cytotoxin, e.g., an auristatin such asMMAE (Monomethyl auristatin E). Moreover, described is a pharmaceutical composition comprising said ADC and at least one pharmaceutically acceptable ingredient. Further, described method of treating a patient suffering from, being at risk of developing, and / or being diagnosed for a neoplastic disease.

The invention belongs to the technical field of gene engineering and protein engineering, and particularly relates to thermal-stable D-psicose 3-epimerase as well as a preparation method and application thereof. According to the invention, a series of D-psicose 3-epimerase DAE mutants are constructed, and six mutants which not only can retain good catalytic activity, but also have high thermal stability are obtained through screening. The catalytic temperature of the three mutants A19D / A223P / V241I is increased by 25 DEG C compared with that of a wild type, while the three mutants A19D / A223P / V241I still show the optimal thermal stability, the catalytic activity of the three mutants is improved by 17.0%, and the three mutants show good industrial suitability. The D-psicose 3-epimerase DAE mutant with improved thermal stability provided by the invention is beneficial to improving the production efficiency of the DAE in industrial application of D-psicose, and provides powerful industrial enzyme guarantee for large-scale and low-cost preparation of D-psicose.

The invention belongs to the field of metabolic engineering, and discloses a genetically engineered bacterium for producing myo-inositol as well as a construction method and application of the genetically engineered bacterium. The genetically engineered bacterium takes escherichia coli as an original strain, and is obtained by performing the following gene editing on a genome of the escherichia coli: non-expressed lactose operon repressor protein, glucose phosphate dehydrogenase, acetokinase, glucose phosphate isomerase and glycerol repressor protein; and overexpressing inositol-1-phosphate synthase, inositol monophosphate, glucokinase, glucose permease and glycerol kinase. Compared with the prior art, the genetically engineered bacterium disclosed by the invention has remarkable advantages in the aspects of key enzyme expression rate, metabolism specificity, fermentation period and the like, and an efficient, stable, economical and feasible solution is provided for industrial production of myo-inositol.

The invention discloses a cellobiose 2-epimerase mutant as well as a gene, an expression vector, recombinant bacteria, a preparation method and application thereof. The mutant is obtained by performing the following point mutation on an amino acid sequence as shown in SEQ ID No.1: S12A, S24A, G131A, G176A, G224A, K46R, K69R, K72R, K91R, K103R, K201R, K219R, K223R, K241R, K263R, K266R, K273R, K284R, K325R, K335R, K349R and K387R. The invention further discloses a preparation method of the mutant. The invention further discloses a gene segment, a plasmid and a recombinant bacterium for recombinant expression of the mutant, and the gene segment, the plasmid and the recombinant bacterium are used for recombinant expression preparation of the mutant. The mutant can be used for continuously and stably catalyzing and preparing lactulose at high temperature, is relatively good in thermal stability and has a relatively good industrial application prospect.

The invention discloses saccharomyces cerevisiae with high yield of salidroside as well as a construction method and application of the saccharomyces cerevisiae. According to the recombinant saccharomyces cerevisiae, ribulose-5-phosphate isomerase RKI1 and transketolase TKL1 are expressed in host bacteria, so that precursor supply is increased; reverse methyltransferase ARO2 and phenylalanine decarboxylase ARO10 are expressed at the same time, and a tyrosine branch pathway is adjusted; then, UDP-glycosyl transferase of different sources is expressed, and iterative site-specific mutagenesis is carried out on the UDP-glycosyl transferase to enhance conversion of hydroxytyrosol to salidroside; the salidroside production performance of the recombinant strain is verified on the basis of a precursor supply pathway, a tyrosine regulation pathway and key enzyme screening, and the salidroside production capacity of the saccharomyces cerevisiae is further improved.

The invention discloses a recombinant bacterium capable of increasing the yield of alpha-bisabolol as well as a preparation method and application of the recombinant bacterium, and belongs to the technical field of microorganisms. The invention aims to improve the yield of alpha-bisabolol and enhance the tolerance of a host to an organic solvent. The invention provides a recombinant bacterium for improving the yield of alpha-bisabolol. Escherichia coli is used as a starting strain; the method comprises the following steps of: overexpressing an acetyl CoA acyltransferase / HMG-CoA reductase mvaE gene, an HMG-CoA synthetase mvaS gene, a 2-methyl citrate dehydratase prpD gene, a mevalonate kinase ERG12 gene, a mevalonate 5-phosphate kinase ERG8 gene, a mevalonate 5-diphosphate decarboxylase ERG19 gene and an isopentenyl diphosphate isomerase idi gene, so as to obtain a recombinant vector; the gene is obtained from an alpha-bisabolol synthase gene of artichoke, a farnesyl diphosphate synthase ispA gene and an alpha-bisabolol synthase CcBOS gene of artichoke. The industrial process of synthesizing alpha-bisabolol by a biological method is promoted.

The application discloses a D-allulose 3-epimerase mutant, a preparation method and application thereof, and relates to the fields of genetic engineering and enzyme engineering. The amino acid sequence of the D-allulose 3-epimerase mutant is shown as SEQ ID NO. 1. The specific enzyme activity of the D-allulose 3-epimerase mutant provided by the application is increased from 10.21 U / mg of a control (before mutation) to 15.29 U / mg at 80 DEG C and pH 6.0; and the equilibrium conversion rate is increased from 29.98% of the control (before mutation) to 36.26% when the substrate is 700 g / L of fructose. The D-allulose 3-epimerase mutant provided by the application has higher catalytic activity, and has a very broad application prospect in the efficient production and preparation of D-allulose.

The invention discloses recombinant saccharomyces cerevisiae, a 11-seed oil fermentation product as well as a preparation method and application of the 11-seed oil fermentation product, and belongs to the technical field of synthetic biology and fermentation product preparation. According to the recombinant saccharomyces cerevisiae disclosed by the invention, a caffeic acid coenzyme A ligase 4CL coding gene, a chalcone isomerase CHI coding gene, a flavanone-3-hydroxylase F3H coding gene and a chalcone synthase CHS mutant coding gene are over-expressed, and the chalcone synthase CHS mutant is preferably Y69H / H71Y / Q161K. The preparation method of the 11-seed oil fermentation product comprises the following steps: fermenting a recombinant saccharomyces cerevisiae fermentation solution in the presence of a sophora flower bud extract and caffeic acid to obtain a first fermentation solution; fermenting the lactic acid bacteria fermentation liquor in the presence of 11 seed oil to obtain second fermentation liquor; and mixing the first fermentation liquid and the second fermentation liquid, continuing fermentation, and respectively collecting an oil phase and a water phase after fermentation is finished, so as to obtain a fermentation product. The product provided by the invention has multivitamin antioxidant activity.

A specific topoisomerase inhibitor, a use as an antibody drug conjugate, and a preparation method therefor, which relate to the technical field of medicinal chemistry. The inhibitor is a compound A or a tautomer, a mesomer, a racemate, an optical antipode, a diastereoisomer, or a mixture form thereof, or a pharmaceutically acceptable salt thereof; the structure of the compound A is such that the compound may also be further prepared to obtain an antibody drug conjugate, the antibody drug conjugate has good solubility and pharmaceutical properties, and the conjugation process does not result in precipitation, the antibody drug conjugate exhibits obvious in-vivo anti-tumor activity, and shows markedly stronger anti-tumor activity when compared with a control sample.

Disclosed herein are genetically engineered Kluyveromyces sp. cells capable of producing D-allulose. The genetically engineered Kluyveromyces sp. cells comprise an exogenous polynucleotide sequence encoding an allulose-6-phosphate 3-epimerase enzyme at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, at least 99%, or100% identical to at least one of SEQ ID NOs:249-256, 258, and 259; and an exogenous polynucleotide sequence encoding an allulose-6-phosphate phosphatase enzyme at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, at least 99%, or 100% identical to at least one of SEQ ID NOs:87, 89, 190, 123, 105, 107, 115, 83, 95, 113, 117, 119, 121, 127, 131, 137, 145, 169, 173, 179, and 183.

This invention discloses a ketoisomerase mutant and a method for preparing D-chiral inositol, belonging to the field of genetic engineering technology. The ketoisomerase mutant is obtained by mutating the 73rd amino acid of the amino acid sequence shown in SEQ ID NO.3 from L to N. The ketoisomerase mutant L73N obtained by this invention further enhances enzyme activity. When catalyzing the reaction of muscle inositol to synthesize D-chiral inositol together with inositol dehydrogenase, it can further improve the conversion rate and the yield of D-chiral inositol.

Disclosed herein are genetically engineered Kluyveromyces marxianus cells capable of producing D-allulose with increased talitol formation. The engineered cell may comprise a genetic modification resulting in overexpression of a native talitol dehydrogenase enzyme; an exogenous polynucleotide sequence encoding an allulose-6-phosphate 3-epimerase enzyme at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, at least 99%, or 100% identical to at least one of SEQ ID NOs:249-256, 258, and 259; and an exogenous polynucleotide sequence encoding an allulose-6-phosphate phosphatase enzyme at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, at least 99%, or 100% identical to at least one of SEQ ID NOs:87, 89, 190, 123, 105, 107, 115, 83, 95, 113, 117, 119, 121, 127, 131, 137, 145, 169, 173, 179, and 183.

This invention discloses a ketoisomerase mutant and its application in the preparation of D-chiral inositol, belonging to the field of genetic engineering technology. The ketoisomerase mutant is obtained by mutating the amino acid sequence shown in SEQ ID NO.1, specifically by mutating amino acid position 62 and / or amino acid position 175 of the amino acid sequence shown in SEQ ID NO.1. After the above-mentioned mutation of the wild-type thermostable ketoisomerase, the resulting ketoisomerase mutant not only retains the advantages of the wild-type thermostable ketoisomerase—its heat resistance and susceptibility to temperature fluctuations—but also exhibits higher enzyme activity. When co-catalyzing the reaction of muscle inositol to D-chiral inositol with inositol dehydrogenase, it can further improve the conversion rate and yield of D-chiral inositol even at high substrate concentrations.

The invention provides a method for producing L-carnosine, a genetic engineering strain as well as a preparation method and application of the genetic engineering strain, and belongs to the field of genetic engineering. According to the genetic engineering strain provided by the invention, by knocking out a glucose-6-phosphate isomerase coding gene pgi, knocking out an L-threonine / L-homoserine transporter coding gene rhtA or knocking out a dipeptide transfer protein coding gene dppABCD, the yield of extracellular L-carnosine is increased, the shake flask yield of the finally constructed strain reaches 9.1 g / L, the 5L fermentation tank yield reaches 65 g / L, and the yield of the extracellular L-carnosine reaches 9.1 g / L; and the method has a good application prospect in L-carnosine biosynthesis.

The invention belongs to the technical field of medical chemistry, and discloses a 5-O-carbon mould amine tylosin lactone derivative with a double-target combined antibacterial effect as well as a preparation method and application of the 5-O-carbon mould amine tylosin lactone derivative. The derivative is a compound as shown in a formula I, and pharmaceutically acceptable salt, eutectic, tautomer, polymorphic substance, solvate, prodrug or isotope labeled compound thereof. The compound can act on a bacterial ribosome 50S subunit and DNA topoisomerase IV at the same time, and shows an excellent antibacterial effect in an antibacterial activity test, and the minimum inhibitory concentration (MIC) reaches 0.0625 mu g / mL. The compound has the advantages of being high in antibacterial activity, wide in antibacterial spectrum and capable of achieving rapid sterilization, and a new choice is provided for developing drugs with antibacterial activity.

This disclosure provides an E. coli strain, which lacks thioredoxin reductase activity encoded by trxB and thioredoxin 1 activity encoded by trxA, and glutathione reductase activity encoded by gor. Said E. coli strain expresses a mutated AhpC protein having glutathione reductase activity and a cytosolic prokaryotic disulfide isomerase. The E. coli strain has an oxidative cytosol and can be used to efficiently produce proteins having disulfide bonds.

Compositions are disclosed that include at least one protein disulfide isomerase or a biologically active fragment or variant thereof. Methods of producing and using the compositions are also disclosed. In particular (but not by way of limitation), methods are provided for reducing blood glucose, treating hyperglycemia, treating or reducing the occurrence of type 1 diabetes, treating or reducing the occurrence of type 2 diabetes, and / or treating or reducing the occurrence of type 3 diabetes (i.e., Alzheimer's Disease) by administering the composition that includes the at least one protein disulfide isomerase. The protein disulfide isomerase may be administered alone or may be administered simultaneously or sequentially with one or more additional active agents.

The invention belongs to the technical field of enzyme engineering, and particularly relates to an immobilized enzyme preparation containing D-psicose-3-epimerase cells as well as a preparation method and application of the immobilized enzyme preparation. The preparation method comprises the following steps: carrying out fermentation culture on genetically engineered bacteria containing thermal-stability D-psicose-3-epimerase to obtain wet thalli, mixing the thalli with egg shells and a diatomite carrier, immobilizing the obtained mixture on the carrier through a cross-linking agent, and carrying out separation, drying and granulation to obtain the immobilized enzyme preparation. According to the invention, the affinity between the immobilized carrier and microorganisms is stronger; the prepared immobilized enzyme preparation is high in mechanical strength and stable in enzyme activity, is used for preparing D-psicose through D-fructose isomerization, and is high in conversion efficiency. Under the condition of 60 DEG C, after the batch reaction is repeated for 10 batches, the conversion rate is still greater than 28%; 700g / L fructose solution is used as a substrate, the reaction is continuously carried out for 31 days, the average conversion rate is 28% or above, and the method has relatively high industrial advantages.

The present invention relates to a method for producing α-sialyl-β-D-galactoside saccharides, particularly α-sialyl-(2→3)-β-D-galactoside saccharides and α-sialyl-(2→6)-β-D-galactoside saccharides, from a β-D-galactoside saccharide, a sialic acid donor, and an enzyme with β-galactoside α-sialyltransferase activity. The enzymes with β-galactoside α-sialyltransferase activity used herein do not exhibit catalytic activity towards the hydrolysis of cytidine 5'-monophospho-N-acetyl-neuraminic acid to cytidine and N-acetyl-neuraminic acid. The method can be performed in vitro and in vivo using a genetically engineered cell comprising a nucleic acid encoding said enzyme. Further, said process may be adapted to produce the sialic acid donor CMP-Neu5Ac from low-cost substrates N-acetyl-D-glucosamine (GlcNAc), pyruvate, a cytidine phosphate (CMP, CDP or CTP) and polyphosphate in a single reaction mixture with a set of optionally immobilized or optionally co-immobilized enzymes comprising N-acylglucoamine 2-epimerase (AGE), an N-acetylneuraminate lyase (NAL), an N-acylneuraminate cytidylyltransferase (CSS), optional a uridine kinase (UDK), a uridine monophosphate kinase and a polyphosphate kinase 3 (PPK3).

This invention belongs to the field of synthetic biology and microbial engineering, and discloses a chemical-biological method for preparing the isopentenyl bibenzyl compound 2-isopentenyl-3,3',4',5-tetrahydroxybibenzyl (NPB-1575) which has anti-ischemic stroke activity. The specific disclosed method includes: (1) chemically synthesizing the substrate dihydropiperidine; (2) constructing an engineered Escherichia coli strain based on the isopentenyl utilization pathway, co-expressing hydroxyethylthiazol kinase, isopentenyl phosphokinase, isopentenyl pyrophosphate isomerase and specific isopentenyl transferase, and efficiently synthesizing the isopentenyl donor; (3) using this strain to catalyze dihydropiperidine in whole cells, the yield in a 200L fermenter can reach 2.54g / L, which is nearly 40 times higher than the existing method; (4) obtaining NPB-1575 with a purity >98.5% by macroporous adsorption resin and normal / reversed phase chromatography and recrystallization. This method uses readily available raw materials, involves simple steps, is environmentally friendly, and yields high purity, laying the foundation for the development of NPB-1575 as a new drug for ischemic stroke and showing significant application potential.

The invention relates to the technical field of biology, in particular to a hexanose-2-epimerase mutant and application thereof. According to the hexaldehyde aldose-2-epimerase mutant and the application of the hexaldehyde aldose-2-epimerase mutant in the embodiment of the invention, the hexaldehyde aldose-2-epimerase mutant generates mutation beneficial to improvement of hexaldehyde aldose-2 hydroxyl isomerization catalytic activity at at least one key site in an amino acid sequence as shown in SEQ ID NO: 19; through the mode, the hexaldehyde sacchar-2-epimerase mutant shows excellent hexaldehyde sugar C-2 hydroxyl isomerization catalytic activity, can efficiently convert D-glucose into D-mannose, and is beneficial to improving the synthesis efficiency of the D-mannose.

The invention discloses a preparation method of an L-rhamnose isomerase mutant and a preparation method of D-allose, and belongs to the technical field of genetic engineering. The amino acid sequence of the L-rhamnose isomerase mutant is as shown in SEQ ID NO. 3. According to the L-rhamnose isomerase mutant disclosed by the invention, the 268th amino acid of the amino acid sequence of the wild type L-rhamnose isomerase is mutated from S to T, and the enzyme activity of the obtained L-rhamnose isomerase mutant is remarkably improved, so that the catalytic efficiency is improved when the D-allose is prepared by catalyzing the reaction of D-psicose, and the yield of the D-allose is further improved.

The disclosure relates to the field of specialty chemicals and methods for their synthesis. In embodiments, the disclosure provides viable bacterial cells which comprise heterologous dual 3-hydroxy-acyl-ACP dehydratase / isomerases, etc. The disclosure further provides monounsaturated fatty acid derivative molecules produced by the viable bacterial cells which are non-native to the bacterial cells. The disclosure further provides methods for the preparation and production of non-native monounsaturated fatty acid derivative molecules such as e.g., an ω3-monounsaturated fatty acid derivative, an ω5-monounsaturated fatty acid derivative, an ω9-monounsaturated fatty acid derivative, an ω11-monounsaturated fatty acid fatty acid derivative, etc.