419 results about "Lyase" patented technology

The invention belongs to the field of enzymes, and particularly relates to an alginate lyase Alyw203 mutant with improved thermal stability. According to the invention, mutation is carried out on the basis of alginate lyase Alyw203, and mutants with mutation sites of D40W, S136I, L172V, T206W and D248L are obtained. The thermal stability of the mutant is improved, the improvement of the mutant L172V is most obvious, and the residual activity of the mutant after being incubated at 40 DEG C for 1 hour is improved from 30.46% to 76.59%; the half-life period at 40 DEG C is prolonged to 388.78 min, which is 10.91 times that of the original enzyme, and 37.80% of residual enzyme activity still exists after incubation for 12 h. The invention also provides a coding gene of the mutant, a recombinant expression vector for producing the mutant and a genetically engineered bacterium.

The invention relates to the technical field of microbial metabolism engineering, in particular to a construction method and application of genetically engineered bacteria for efficiently producing O-acetyl-L-homoserine. The construction method specifically comprises the following steps: (1) taking a strain Escherichia coli W3110 as a chassis, and knocking out a homoserine O-succinyl transferase coding gene metA; (2) knocking out a gamma-cystathionine synthetase encoding gene metB; (3) knocking out a cysteine lyase coding gene metC; (4) carrying out weakening expression on an O-acetyl-L-homoserine thiolase coding gene metYcm from the marine cyclobacterium; (5) overexpressing a ribulose diphosphate carboxylase coding gene rbcLSse from the synechococcus elongate; (6) overexpressing a ribulose phosphate kinase coding gene prkse from the synechococcus slender; and (7) weakening the expression of the citrate synthase coding gene gltA to obtain the genetically engineered bacterium for efficiently producing the O-acetyl-L-homoserine. The strain provided by the invention is used for producing O-acetyl-L-homoserine, and has the advantages of high yield, high yield and high sugar-acid conversion rate.

The invention provides formaldehyde lyase as well as a mutant and application thereof. The amino acid sequence of the formaldehyde lyase mutant is shown as SEQ ID NO.1, SEQ ID NO.4 or SEQ ID NO.6 and contains at least one of the following sites: S26, W86, N87 or Y87, L109 or M109, L110, H281, Q282 or E282 and A460, and the amino acid sequence is subjected to amino acid mutation and has a formaldehyde lyase activity function. The amino acid sequences of the formaldehyde lyase and the mutants of the formaldehyde lyase have at least 99% of sequence identity with SEQ ID NO.1-7. The formaldehyde lyase and the mutant thereof can catalyze formaldehyde to synthesize 1, 3-dihydroxyacetone, and a new way for converting formaldehyde into 1, 3-dihydroxyacetone is provided.

The invention belongs to the field of enzymes, and particularly relates to an alginate lyase AlgL3199 mutant, a recombinant expression vector and a genetically engineered bacterium. The invention provides an alginate lyase AlgL3199, and mutation is carried out on the basis of the alginate lyase AlgL3199 to obtain a mutant of which the mutation sites are K81A, D148P, V163T, I274G and a combination of the K81A, the D148P, the V163T and the I274G. The specific activity of the mutant enzyme and the thermal stability of a part of mutants are improved, the thermal stability of a mutation site K81A is improved most remarkably, the residual activity of the mutant enzyme after being incubated at 60 DEG C for 2 hours is retained by 52.97%, and the half-life period is 123.12 min and is 5.18 times that of an original enzyme. The invention further provides the alginate lyase AlgL3199, a coding gene of the mutant of the alginate lyase AlgL3199, a recombinant expression vector for producing the alginate lyase and a genetic engineering bacterium.

The invention provides a kit for rapidly detecting MRSA and drug-resistant gene nucleic acid POCT of the MRSA based on a phage lyase mutant. The kit comprises nucleic acid extraction and purification and triple PCR rapid amplification detection reagents. The staphylococcus aureus bacteriophage lyase mutant nucleic acid release liquid containing the amino acid sequence as shown in SEQ ID NO: 1 is adopted, wall breaking can be rapidly conducted on staphylococcus aureus, and nucleic acid is released. The effect of the nucleic acid release liquid acting for 5 minutes is equivalent to or even better than that of the lysozyme acting for 60 minutes; according to the present invention, with the combination of the MRSA and drug-resistant gene triple PCR rapid amplification detection reagent, the total detection time is only 35 min, the time is saved by 55 min or more than 55 min compared with the lysozyme method, and the MRSA and drug-resistant gene nucleic acid POCT rapid detection can be achieved;

The invention discloses methanogen lyase homologous with a PeiR lyase sequence and application of the methanogen lyase, and aims to solve the problem that PeiR lyase protein of a methanogen cell wall peptide bond can participate in a biological process of hydrolyzing archaea cell walls, effectively kill methanogen and reduce methane production, and protein homologous with the PeiR lyase protein has potential methane reduction potential. According to the invention, a series of biological information software is utilized to identify protein sequences coded by methanogens virus from rumen microbiome sequencing data, and sequence homology between the proteins and PeiR protein is further analyzed to obtain a series of methanogens lyases. In order to realize the expression of the lyase, multiple segments of primers are designed to synthesize a target sequence, and the target sequence is successfully expressed in a prokaryotic expression system. Through the detection of crude enzyme liquid, the effectiveness of the lyase in the aspect of reducing the methane yield is verified in an in-vitro gas production test.

The invention belongs to the technical field of biology, and discloses a yarrowia lipolytica engineering strain for efficiently producing eicosapentaenoic acid based on citric acid metabolism regulation, a method and application of the yarrowia lipolytica engineering strain. Delta9 elongase, Delta8 desaturase, Delta5 desaturase and Delta17 desaturase genes in a fatty acid synthesis route, heterologous ATP-citrate lyase and a mitochondrial citric acid vector are overexpressed. According to the invention, ATP-citric acid lyase and a mitochondrial citric acid carrier gene which are respectively derived from Schizochylene sp. And Saccharomyces cerevisiae are jointly expressed in the yarrowia lipolytica engineering strain, so that the yields of EPA and grease in the yarrowia lipolytica engineering strain are remarkably improved, and compared with a control strain, the yields of the grease and the EPA are respectively improved by 243.35% and 161.85%.

The invention relates to ulva polysaccharide lyase JpPL40A and application thereof, and belongs to the technical field of functional enzymes, the amino acid sequence of the ulva polysaccharide lyase JpPL40A is as shown in SEQ ID NO.1, and the coding gene of the ulva polysaccharide lyase JpPL40A is as shown in SEQ ID NO.2 or SEQ ID NO.3. The invention further discloses a preparation method of the ulva polysaccharide lyase JpPL40A. The ulva polysaccharide lyase JpPL40A disclosed by the invention can be used for hydrolyzing ulva to obtain unsaturated ulva disaccharide, tetrasaccharide, hexasaccharide and / or octasaccharide.

The invention relates to pectin lyase as well as a mutant, a recombinant expression vector and application thereof. The nucleotide sequence of the pectin lyase is as shown in SEQ ID NO.1, the full length of the gene is 1056 bp, 352 amino acids are coded in total, and the amino acid sequence is as shown in SEQ ID NO.2; the pectin lyase mutant is formed by site-directed mutagenesis on the basis of an amino acid sequence of pectin lyase, a mutated nucleotide sequence is as shown in SEQ ID NO.3, and the amino acid sequence is as shown in SEQ ID NO.4; compared with the existing pectin lyase, the pectin lyase and the mutant thereof provided by the invention have the characteristics of high activity and temperature stability, and can be widely applied to fruit juice extraction, fruit juice clarification and fruit and vegetable juice beverage processing.

The invention discloses methanogen lyase homologous with high-dimensional characteristics of PeiW lyase and application of the methanogen lyase, and aims to solve the problem that PeiW lyase protein of methanogen cell wall peptide bonds can participate in the biological process of hydrolyzing archaea cell walls, effectively kill methanogen and reduce methane production, and protein homologous with the protein has potential methane reduction potential. According to the method, a series of bioinformatics software is utilized, a protein sequence coded by methanogens virus is identified from a large amount of rumen microorganism virus group sequencing data, the high-dimensional homology of a deep learning model between the protein sequence and PeiW is analyzed, and two methanogens lyases similar to the high-dimensional characteristics obtained by the PeiW model are obtained. In order to realize the expression of the lyase, multiple segments of primers are designed to synthesize a target sequence, and the target sequence is successfully expressed in a prokaryotic expression system. Through detection of a crude enzyme solution, the effectiveness of the lyase in the aspect of reducing the yield of methane is verified in an in-vitro gas production test.

The invention relates to a preparation method of a 3D printing high-density cell tubular vascular graft. The preparation method comprises the following steps: sucking a supernatant obtained by centrifuging a cell suspension away and only remaining bottom pure cells; the preparation method comprises the following steps: uniformly stirring and mixing OMA, pig gelatin and an LAP photoinitiator in a Hank's solution to form a hydrogel precursor solution; extruding the pure cells and the hydrogel precursor solution from a three-axis nozzle by using printing equipment, and immersing the pure cells and the hydrogel precursor solution into a calcium chloride solution; lyase is added to degrade the hydrogel precursor solution, the hydrogel precursor solution is completely degraded, and an independent single-layer pipeline structure with only a remaining pure cell layer is obtained. The invention provides a method for manufacturing high-density pure-cell lumen constructs to mimic native blood vessels by using a self-made microfluidic coaxial 3D bioprinting device. And after the support hydrogel on the inner layer and the outer layer is removed, a single-layer tubular structure of high-density MOVAs only limited to pure cells is obtained. The cells in the pure cell vascular constructs exhibit good cell viability and cell function.

The invention discloses methanogen lyase with the same protein family annotation as PeiR lyase and application of the methanogen lyase, and the methanogen lyase is obtained through homologous screening of Pfam protein family database annotation based on known PeiR lyase characteristics aiming at methanogen cell wall peptide bonds. The PeiR lyase protein can participate in the biological process of hydrolyzing archaea cell walls, methanogens are effectively killed, methane production is reduced, and the protein homologous with the protein has potential methane reduction potential. According to the invention, by integrating metagenome sequencing data of rumen microorganisms, screening methanogenic bacterium virus protein by using series bioinformatics software, and combining Pfam functional domain annotation to carry out homologous relationship analysis, a series of lyase is finally identified and is successfully expressed in a prokaryotic expression system, and meanwhile, an in-vitro gas production experiment result also shows that the methanogenic bacterium virus protein can be successfully expressed in a prokaryotic expression system. The crude enzyme liquid can significantly reduce the methane generation amount.

The invention discloses methanogen lyase homologous with high-dimensional characteristics of PeiR lyase and application of the methanogen lyase and aims to solve the problems that PeiR lyase protein of methanogen cell wall peptide bonds can participate in the biological process of hydrolyzing archaea cell walls, methanogen is effectively killed, methane production is reduced, and protein homologous with the protein has potential methane reduction potential. According to the invention, a series of biological information software is utilized to identify protein sequences coded by methanogen viruses from a large amount of rumen microbiome sequencing data, and high-dimensional homology between the proteins and PeiR proteins based on a deep learning model TM-Vec is further analyzed, so that a series of methanogen lyases are obtained. In order to realize the expression of the lyase, multiple segments of primers are designed to synthesize a target sequence, and the target sequence is successfully expressed in a prokaryotic expression system. Through the detection of crude enzyme liquid, the effectiveness of the lyase in the aspect of reducing the methane yield is verified in an in-vitro gas production test.

The invention belongs to the technical field of bioengineering, and particularly relates to alginate lyase Alaa1 as well as a modification method and application thereof. The amino acid sequence of the alginate lyase Alya1 is as shown in SEQ ID NO. 1, and the nucleotide sequence of the Alya1 gene for coding the alginate lyase Alya1 is as shown in SEQ ID NO. 2. The 406th glutamic acid of the alginate lyase Alya1 is mutated into histidine or lysine, and the high temperature resistance, the thermal stability, the pH stability and the half-life period of the alginate lyase Alya1 are remarkably improved.

The invention relates to ulva polysaccharide lyase PcPL40A and application thereof, and belongs to the technical field of functional enzymes, the amino acid sequence of the ulva polysaccharide lyase PcPL40A is as shown in SEQ ID NO.1, and the coding gene of the ulva polysaccharide lyase PcPL40A is as shown in SEQ ID NO.2 or SEQ ID NO.3. The invention further discloses a preparation method of the ulva polysaccharide lyase PcPL40A. The ulva polysaccharide lyase PcPL40A disclosed by the invention can be used for hydrolyzing ulva to obtain unsaturated ulva disaccharide, tetrasaccharide, hexasaccharide and / or octasaccharide.

The invention relates to low-viscosity sodium alginate, a preparation method and a soft capsule shell containing a pure sodium alginate component, and belongs to the technical field of biochemical engineering, the viscosity and molecular weight of the low-viscosity sodium alginate are 15mPa. S and 273.08 kDa; the molecular weight is 30 mPa.s and the molecular weight is 310.5 kDa; according to the present invention, the ratio of the Da to 665.43 kDa is 20.48%, the ratio of the Da to 444.79 kDa is 16.87%, and the ratio of the Da to 322.06 kDa is 62.66%; or when the molecular weight is 70 mPa.s, the molecular weight of 466.92 kDa accounts for 44.27%, and the molecular weight of 329.27 kDa accounts for 55.73%. The invention also provides a preparation method of the low-viscosity sodium alginate, which comprises the following steps: dissolving the sodium alginate as a raw material, carrying out enzymolysis by using alginate lyase, sampling at regular time, measuring the viscosity, carrying out enzyme deactivation treatment on the enzymatic hydrolysate when the viscosity reaches the specified viscosity, and carrying out evaporation concentration, alcohol precipitation, drying and crushing to obtain the low-viscosity sodium alginate. The low-viscosity sodium alginate can be used for preparing a soft capsule shell which is stable in property and good in enteric characteristic.

Provided are a novel sodium alginate lyase AlyB, a preparation method therefor and the use thereof. The main cracking product of the novel sodium alginate lyase AlyB is a monosaccharide, which has the effects of resisting oxidation, resisting viruses and inhibiting an angiotensin converting enzyme, and thus can be applied to the fields of cosmetics, medicines, healthcare foods and the like.

The invention relates to the technical field of biological materials, in particular to a pH response collagen microneedle patch loaded with antibacterial nanoparticles as well as a preparation method and application of the pH response collagen microneedle patch loaded with the antibacterial nanoparticles, and the microneedle patch is prepared by loading the antibacterial nanoparticles, aldehyde modified F127 and recombinant three-type collagen COL3 on a polymer matrix. When the microneedle patch is applied to a chronic wound of a diabetic patient, the microneedle penetrates through the skin in a minimally invasive mode and directly reaches a wound focus area. Under the irradiation of 808nm near-infrared light, the mesoporous polydopamine absorbs light energy, so that the loaded lyase LysAB2 is quickly released, bacterial cell walls are specifically recognized and cracked, and bacteria are efficiently killed; meanwhile, the collagen hydrogel constructs an appropriate microenvironment at the wound, cell adhesion, proliferation and migration are promoted, and the wound healing process is accelerated. Compared with a traditional diabetes mellitus chronic bacterial infection wound treatment means, the microneedle patch provided by the invention provides an efficient and safe new strategy for treating the chronic bacterial infection wound of a diabetes mellitus patient.

The invention discloses a bacteriophage lyase and application thereof, and particularly relates to a bacteriophage lyase with an amino acid sequence as shown in SEQ INNO.2. The bacteriophage lyase can inhibit the growth of escherichia coli, staphylococcus and salmonella, can be used as an antibacterial substance in splitting gram-negative bacteria and can be used for preparing drugs for resisting gram-negative bacteria. The lyase can be used independently or compounded with other substances, the use concentration of antibiotics can be reduced by combining the lyase with the antibiotics, toxic and side effects (such as renal toxicity of polymyxin) of drugs are reduced, and meanwhile, generation of bacterial drug resistance is delayed. After the lyase and the chitosan are combined for use, remarkable antibacterial activity is generated, the antibacterial effect can be achieved without pre-treatment on bacteria, and the practicability is improved.

The invention relates to a process for producing three recombinases capable of hydrolyzing organophosphorus, carbamate and pyrethroid insecticides, and preparations containing these enzymes. The present invention provides recombinant plasmid DNA vectors in which the protein secretion system has been modified to improve the ability of recombinant proteins to secrete into the space around the plasmid or culture medium. A nucleotide sequence for coding a PelB (butyric acid lyase B) signal sequence is deleted and substituted by a nucleotide sequence for coding a LamB (maltodextrin or phage lambda receptor) signal sequence, so that the secretion efficiency of the recombinant protein is higher. The invention discloses three recombinant plasmid DNA (deoxyribonucleic acid) vectors which are constructed by utilizing the improved plasmid DNA vectors and are used for expressing recombinant proteins. The recombinant protein comprises (a) a recombinant organophosphate hydrolase having at least 80% sequence identity with the amino acid sequence of methyl parathion hydrolase (MPH) (Protein Database (PDB) ID: 1P9E) as shown in SEQ ID NO: 1, wherein the recombinant organophosphate hydrolase has hydrolytic activity on organophosphate insecticides; (b) a recombinant carbamate hydrolase having at least 80% sequence identity with the amino acid sequence of L-aminopeptidase-D-Ala-esterase / amidase (aryl amidase) (MAH) (PDB ID: 1B65), as shown in SEQ ID NO: 2, wherein the recombinant carbamate hydrolase has hydrolytic activity on carbamate insecticides; and (c) a recombinant pyrethroid hydrolase having at least 80% sequence identity with the amino acid sequence of the pyrethroid hydrolytic carboxylesterase (EstA) (PDB ID: 4CCY) as shown in SEQ ID NO: 3, wherein the recombinant pyrethroid hydrolase has hydrolytic activity on a pyrethroid insecticide. The embodiment of the invention further provides three recombinant bacterial strains, an escherichia coli strain BL21 (DE3) is used as a host cell, and each recombinant plasmid DNA vector is used for transformation. The invention also discloses culture conditions of the recombinant strain, wherein the culture conditions comprise culture medium composition, induction conditions and enzyme harvesting and enzyme activity detection methods. In addition, the embodiment of the invention also provides a preparation which contains the three recombinases as functional components.

The invention provides low-temperature alginate lyase and application thereof, namely alginate lyase with low-temperature catalytic activity, which is separated from marine-derived cold monad bacteria, and the amino acid sequence of the alginate lyase is SEQ ID NO: 1; the amino acid sequence of the alginate lyase after the signal peptide is removed is SEQ ID NO: 3. The algin lyase Alg3889 provided by the invention has the optimal reaction temperature of about 10-16 DEG C, has good temperature stability, and still keeps more than 70% of enzyme activity after being incubated at 0-70 DEG C for 1 hour; the optimum pH value of the strain is 8.0, after the strain is incubated in a buffer system with the pH value of 3.0-10.6 for 12 h, about 90% of the highest enzyme activity can be kept, and the strain has high acid resistance and alkali resistance. The degradation product of the alginate oligosaccharide is alginate oligosaccharide with the polymerization degree of 2-6, and the alginate oligosaccharide has high application value.

The invention discloses a method for producing p-coumaric acid through double-enzyme cascade catalysis, which comprises the following steps: taking phenol, pyruvic acid and ammonium chloride as substrates, and carrying out cascade enzyme catalytic reaction on a tyrosine phenol lyase product and a tyrosine ammonia lyase product to synthesize p-coumaric acid. According to the method, phenol, pyruvic acid and ammonium chloride are used as substrates, a tyrosine phenol lyase product and a tyrosine ammonia lyase product are used as catalysts, the tyrosine phenol lyase product can convert the substrates into L-tyrosine, and the tyrosine ammonia lyase product can directly use the L-tyrosine as the substrate to convert the L-tyrosine into p-coumaric acid. Therefore, the tyrosine phenol lyase product and the tyrosine ammonia lyase product can realize cascade enzyme catalytic reaction in the same reactor, phenol with lower cost can be adopted as a conversion substrate, separation and purification of an intermediate product L-tyrosine are avoided, and the whole process flow is simple and efficient.

The invention relates to algin lyase FsAly7Z with high activity and high thermal stability, which is mainly used for producing brown algae trisaccharide, and an engineering bacterium and application of the algin lyase FsAly7Z. The invention provides an alginate lyase FsAly7Z derived from marine uncultured microorganisms and a preparation method of the alginate lyase FsAly7Z. The FsAly7Z has extremely high thermal stability, and compared with the enzyme activity loss of more than 50% after most enzymes are treated at 40 DEG C for 60 min, the FsAly7Z shows remarkably excellent thermal stability under the same condition, and the half-life period of the FsAly7Z exceeds 24 h; the FsAly7Z can be used for efficiently degrading sodium alginate and a polyG section which is difficult to degrade, and meanwhile, the FsAly7Z also shows the catalytic efficiency superior to that of most similar enzymes; and the content of brown algae trisaccharide in the enzymolysis product is high, so that the subsequent separation and purification process can be simplified, and the production cost can be reduced. In a word, the FsAly7Z is extremely high in thermal stability and excellent in catalytic efficiency, has both economical efficiency and conversion efficiency, can efficiently produce alginate oligosaccharide, is used for analyzing the structure and function association of alginate lyase, and has wide market prospects in the fields of medicine, food industry and the like.

The invention provides an application of a CTH inhibitor and / or an xCT inhibitor in preparation of a medicine for inhibiting mammal embryo implantation, and relates to the technical field of medicines. The application effect of a cystathionine-gamma-lyase (CTH) inhibitor and / or a solute carrier family 7 member 11 (xCT) inhibitor in inhibition of mammalian embryo implantation is verified through research. The research result shows that the xCT inhibitor and / or the CTH inhibitor can obviously inhibit proliferation of corpus luteinized granular cells and secretion of progesterone of a model mouse; meanwhile, by injecting the xCT inhibitor and / or the CTH inhibitor into the mouse model in vivo, ovary ovulation and the maturation rate of the ovulated oocyte nucleus can be remarkably inhibited, functional corpus luteum formation and embryo implantation can be remarkably reduced, and then a new thought and method are provided for development of contraceptive drugs.

The invention discloses a gelatin microcarrier lysate as well as a preparation method and application thereof. The gelatin microcarrier lysis buffer comprises lyase, a cell protective agent, a cell energy metabolism protective agent, an antioxidant, a buffer solution and a chelating agent. The gelatin microcarrier lysate has extremely strong protectiveness to cells, abandons damaging trypsin and EDTA, and innovatively adds a cell protection combination of a cell protective agent L-arginine, a cell energy metabolism protective agent sodium pyruvate and an antioxidant vitamin C, so that the cell survival rate (gt; 98%) and the retention rate (gt; the method is high in cell yield, good in safety and wide in range.

The invention belongs to the technical field of bioengineering, and particularly relates to kluyveromyces marxianus engineering bacteria for synthesizing eicosapentaenoic acid and application of the kluyveromyces marxianus engineering bacteria. According to the engineering bacterium, pyruvate decarboxylase PDC1 genes, alcohol dehydrogenase ADH1 genes and alcohol dehydrogenase ADH2 genes are sequentially knocked out from a kluyveromyces marxianus FIM1 delta ura3 strain; meanwhile, a citrate lyase ACL gene, a pyruvate oxidase PO gene and a phosphate transacetylase PTA gene are inserted into the loci respectively, so that synthesis of acetyl coenzyme A is enhanced; then a plurality of genes are sequentially inserted into a Kluyveromyces marxianus genome, and then a vector of a delta 8 desaturase delta 8D gene is transferred into the Kluyveromyces marxianus genome. The invention also provides a method for efficiently preparing the EPA, namely the Kluyveromyces marxianus engineering strain is used as a fermentation strain, glucose, a yeast extract, peptone and other components are used as a culture medium, and the yield of the EPA produced by culturing and fermenting reaches 8.71 mg / g of dry cell weight.

The invention provides an alginate lyase mutant Amut8C as well as a coding gene and application thereof, belongs to the technical field of gene engineering and enzyme engineering, and can solve the problem that existing alginate lyase cannot meet the requirements of severe reaction conditions such as high temperature and acidity in industrial application. The amino acid sequence of the alginate lyase mutant Amut8C disclosed by the invention is as shown in SEQ ID NO. 1. According to the space structure of the alginate lyase Algt, disulfide bonds in molecules are analyzed, the alginate lyase is mutated, and the obtained alginate lyase mutant Amut8C has heat resistance, acid and alkali resistance and digestive enzyme tolerance, and compared with the alginate lyase Algt, the alginate lyase mutant Amut8C has the advantages that the content of the alginate lyase mutant Amut8C is increased, and the content of the alginate lyase mutant Amut8C is increased. The alginate oligosaccharide with the polymerization degree of 1-4 prepared from the alginate lyase mutant Amut8C under the same enzymolysis condition is higher in yield. The method can be applied to the fields of feeds, foods, detergents or biofuels.

The invention relates to the isolation and characterisation of one or more aptamers against staphylococcal C-S lyase. The invention also provides aptamers, aptamer-conjugates, and minimal functional fragments thereof which may be used to inhibit the activity of said lyases and thereby inhibit Staphylococcus associated malodour.

The invention belongs to the field of industrial application of microbial fermentation, and relates to a microorganism for efficiently producing ergothioneine as well as a preparation method and application of the microorganism. Specifically, the method comprises the following steps: firstly, artificially creating a promoter with a group response property by utilizing saturation mutation and screening of a fluorescence microscope; then, the promoter is used for mediating host bacterium heterologous histidine methyltransferase, sulfoxide synthase and PLP dependent C-S lyase to improve the yield of ergothioneine; on the basis, an endogenous promoter HisJ of host bacteria is replaced, and endogenous cysteine lyase yhaM is knocked out, so that the yield of the ergothioneine is increased again. According to combination of the above strategies, a heuristic and commercialized production thought is provided for efficient synthesis of ergothioneine, and a foundation is laid for reduction of the synthesis cost of ergothioneine.

The invention discloses alginate lyase OUC-AOSA0A2A, a coding gene of the alginate lyase and application of the alginate lyase OUC-AOSA0A2A in degradation of alginate to prepare alginate oligosaccharides, the alginate lyase OUC-AOSA0A2A can efficiently degrade the alginate to prepare the alginate oligosaccharides, and the invention discloses a method for efficiently preparing the alginate oligosaccharides through the alginate lyase. The final product obtained by degradation is alginate oligosaccharide with the polymerization degree of 4-6, and the obtained alginate oligosaccharide has unique research value. The alginate lyase OUC-AOSA0A2A disclosed by the invention has excellent enzymatic property and specificity, and has important industrial application value and economic value in preparation of alginate oligosaccharide by an enzyme method.