33 results about "Paracoccus" patented technology

The present invention relates to a method for treating a bacterial infection by using Paracoccus wg1 T The invention relates to a method for treating wastewater containing high concentration of inorganic nitrogen, which belongs to the technical field of waste resource utilization and water environment treatment. T The seed liquid after culture is used to treat nitrogen-containing wastewater, and the Paracoccus wg1 of the present invention T , has a very high tolerance to high concentrations of inorganic nitrogen, and has excellent denitrification capabilities under conditions of high concentrations of inorganic nitrogen. Specifically, sodium nitrate is used as the nitrogen source, sodium propionate is used as the carbon source, NO3 ‑ When the ‑N concentration is 6258.85 mg / L‑N, 97.68 mg / L‑N of NO3 can be degraded in 48 hours ‑ -N; ammonium sulfate as nitrogen source, sodium propionate as carbon source, NH4 + When the ‑N concentration is 9326.28 mg / L‑N, 92.28 mg / L‑N of NH4 can be degraded in 48 hours + ‑N. paracoccus wg1 T Biological denitrification treatment of high-concentration inorganic nitrogen wastewater has great application prospects.

The application discloses a formic acid dehydrogenase mutant and application thereof in catalyzing carbon dioxide reduction. Paracoccus The formic acid dehydrogenase from sp.MKU1 is mutated by a site-directed mutation technology Ps The arginine (Arg) at the 223th position of the FDH48 amino acid sequence is mutated into proline (Pro) or the proline (Pro) at the 242th position is mutated into phenylalanine (Phe), and the obtained mutants R223P and P242F have higher catalytic activity, can more effectively catalyze CO2 to generate formic acid in vitro, and have potential application values in efficient activation of CO2 and further conversion into other one-carbon compounds through cascade reactions.

The invention relates to a biomarker for individual recognition and application thereof, and relates to the technical field of biology. The biomarker comprises at least one of the following microorganisms: propionibacterium acnes, staphylococcus epidermidis, marine paracoccus, streptococcus, rhodococcus fence celebrating, staphylococcus, pseudomonas, streptococcus sanguineus, achromobacter xylosoxidans, acinetobacter calcoaceticus, acinetobacter johnsonii, staphylococcus lentus, pseudomonas toralaris and brevundimonas vesicularis. Or enterococcus faecium. The biomarker can provide analysis with higher resolution in the aspect of differential strain information, has a better distinguishing effect, higher accuracy and sensitivity on individual recognition, and can be used as a new technical means for supplementing forensic individual recognition.

The application discloses Paracoccus communis C4-4 and C5-3, the preservation number of which is CGMCC NO:31971 and the classification name of which is Paracoccus communis, and the preservation number of which is CGMCC NO:31972 and the classification name of which is Paracoccus communis. Researches show that C4-4 and C5-3 have strong ecological adaptability and good growth promotion ability, and can improve the internal environment of soil in combination with organic materials. A synthetic microbial population constructed by Paracoccus communis comprises C4-4 and C5-3. Tests prove that the synthetic microbial population comprising C4-4 and C5-3 has the advantages of the synthetic microbial population, the microbial population has high alkali production and growth promotion ability, has good ecological adaptability, the pH adaptation range is 4-8, the manganese stress tolerance can reach 5000 μmol / L, can significantly improve the pH of a culture medium, and has obvious alkalization effect. The synthetic microbial population is used as a microbial agent and is compounded with organic materials to prepare a soil conditioner capable of improving acid soil and promoting plant growth. The conditioner is applied to acid and lean soil, can significantly improve the soil pH, improve the content of soil organic matter, nitrogen, phosphorus and potassium, and promote root growth.

The application provides a high-salt and high-nitrate nitrogen wastewater denitrification method, which comprises the following steps: S1, adjusting the pH of the high-salt and high-nitrate nitrogen wastewater to the range of 5.5-7.5, and adopting a primary full-mixed denitrification tank for denitrification, wherein a composite microbial inoculum is put into the primary full-mixed denitrification tank at one time, and the composite microbial inoculum comprises Marinobacter, Azoarcus, Paracoccus, Bacillus and Pseudomonas; S2, adopting a secondary full-mixed denitrification tank for denitrification of the effluent of step S1; during the operation of the secondary full-mixed denitrification tank, a mud-water mixture is backflowed to the primary full-mixed denitrification tank; S3, the effluent of step S2 is introduced into a degassing tank for degassing; S4, the effluent of step S3 is precipitated in a precipitation tank, and then the effluent is discharged. The composite microbial inoculum is used for treating the high-salt and high-nitrate nitrogen wastewater, and the problems of large treatment facility area and high cost caused by concentrated evaporation or dilution of wastewater and then biochemical treatment in traditional treatment are avoided.

The invention discloses paracoccus versutus and an application thereof, and particularly discloses paracoccus versutus and an application thereof, the paracoccus versutus is paracoccus versutus TYWJ-2, the preservation number is CGMCC No.31068, and the paracoccus versutus is preserved in the China General Microbiological Culture Collection Center on July 2, 2024, the preservation number is CGMCC No.31068, and the preservation number is CGMCC No.31068. The address is located in Institute of Microbiology, Chinese Academy of Sciences, No.3, No.1 Yard, Beichen West Road, Chaoyang District, Beijing, and the postcode is 100101. The Paracoccus verrucosus TYWJ-2 provided by the invention has stronger desulfurization capacity and higher sulfur conversion rate, the 12h sulfide degradation rate reaches 98.1%, the sulfur generation rate reaches 76.8%, and the Paracoccus verrucosus TYWJ-2 has good biological desulfurization application potential.

The present application belongs to the technical field of wastewater treatment, and particularly relates to a seawater breeding wastewater antibiotic removal method based on oyster shell composite filler. Fine gravel, oyster shell and functional mineral are compounded in a fixed volume ratio of 2:1:1, and are laid in a structure with a limited particle size range and homogeneity without stratification. A salinity-directed salt-tolerant domestication process and a tidal intermittent operation mode of 48h hydraulic retention + 24h emptying and reoxygenation are matched, and salt-tolerant functional bacterial flora of Proteobacteria, Paracoccus and Shigella are enriched. The present application can adapt to a wide range of salinity conditions of 10‰-30‰, relieve high salt inhibition and ion competition, simultaneously and efficiently remove three typical antibiotics of conventional pollutants, sulfamethoxazole, trimethoprim and enrofloxacin, and reduce resistance genes. The sulfamethoxazole removal rate can reach 93.94% under the condition of 30‰ high salinity, the system runs stably and has strong adaptability, and has certain engineering application value and large-scale popularization potential in the field of seawater breeding wastewater treatment.

The invention belongs to the technical field of biology, and provides a paracoccus Wheatstone strain and application thereof, the paracoccus Wheatstone strain can produce pyrroloquinoline quinine at high yield, the strain is named as YJY25-02, and the preservation number is CGMCC NO.34258. The strain is subjected to shake-flask aerobic culture for 83h, and the titer of the pyrroloquinoline quinone in fermentation liquor is 176.7 mg / L; the titer of pyrroloquinoline quinine in fermentation liquor during aerobic culture in a fermentation tank is 1796-1863 mg / L, the methanol conversion rate is 16.19-18.12 mg / g, the method has the advantages of short fermentation time, high titer and high methanol conversion rate, and the problem of large-scale production can be solved; pure pyrroloquinoline quinine with the purity larger than or equal to 98% is prepared through separation and purification of fermentation liquor, the yield ranges from 80% to 85%, the high yield and high purity of the pure pyrroloquinoline quinine are achieved, the separation and purification process is simple, the cost is low, organic solvents difficult to remove are not introduced, and the safety of the product is guaranteed.

The invention discloses a method for producing polyhydroxyalkanoate through microbial fermentation and application of the polyhydroxyalkanoate. The method for producing the polyhydroxyalkanoate through microbial fermentation comprises the following steps: optionally adding water into organic acid feed liquid for dilution, and then adding a complex microbial inoculant containing flavobacterium for aerobic fermentation to obtain PHA-rich fermentation thalli; the complex microbial inoculant comprises neosilurus meridionalis, nitrogen-fixing vibrio, dearomatization bacteria, flavobacterium and paracoccus; the organic acid feed liquid is obtained by carrying out acid production fermentation on a pretreated material derived from lignocellulose. According to the method, the lignocellulose is used as a raw material to replace a grain raw material to produce the organic acid under the condition of no enzymolysis. The microbial agent disclosed by the invention contains neosilurus meridionalis, dearomatization bacteria, flavobacterium, flavobacterium and paracoccus, the strains act together, the organic acid can be effectively utilized for further fermentation to generate polyhydroxyalkanoate, and the microbial agent has important economic and environmental benefits.

This invention relates to a phthalate hydrolase mutant and its application in phthalate degradation, belonging to the field of microbial enzyme technology. The amino acid sequence of the phthalate hydrolase mutant HylD1 is shown in SEQ ID NO.1, and the nucleotide sequence of the encoding gene is shown in SEQ ID NO.2. This enzyme can catalyze the reaction to generate MMP using DMP as a substrate; or catalyze the reaction to generate MEP and EMP using DEP as a substrate. In this invention, the encoding gene of the phthalate hydrolase HylD1 from *Paracoccus koningii* BJQ0001 was artificially modified by site-directed mutagenesis at amino acid position 265, resulting in a mutant HylD1 (R265A) with higher activity. Compared with the wild-type phthalate hydrolase HylD1, the absolute enzyme activity of this phthalate hydrolase mutant HylD1 (R265A) in degrading DMP and DEP is increased by 2-fold and 3.6-fold, respectively, and a special product EMP is also produced during the degradation of DEP.

The application discloses a synthetic bacterial flora capable of improving salt tolerance of alfalfa, which is composed of Pseudomonas strain EC5, Agrobacterium strain EC17, Streptomyces strain EC15, Paracoccus strain RH39, Pseudomonas strain RH6, Pseudomonas strain RH37, Sporosarcina strain RH34 and Bacillus strain RH32. The synthetic bacterial flora has the functions of dissolving organic phosphorus, dissolving inorganic phosphorus, dissolving potassium, producing siderophore, producing biofilm, producing IAA and producing ACC deaminase. Seed soaking and germination under the stress of 200 mmol / L and 250 mmol / L NaCl can obviously improve the germination potential, germination rate, germination index, radicle length, plumule length and fresh weight of the group seedling embryo of alfalfa. Under the stress of 200 mmol / L NaCl, seed soaking with the synthetic bacterial flora can significantly improve the plant height, stem diameter, leaf area and fresh and dry weight of the above-ground part of alfalfa.

The invention provides a method for strengthening azo dye decolorization based on co-culture of shewanella and paracoccus denitrificans, and relates to the technical field of microorganism co-culture and bioremediation. The shewanella can reduce various pollutants through extracellular electron transfer, but cannot effectively utilize acetate as a carbon source. Paracoccus denitrificans can efficiently oxidize acetate, but lacks the ability to deliver electrons to extracellular electron acceptors (such as azo dyes). According to the method, the S. oneidensis MR-1 in a stable phase and the P. denitrifans in a logarithmic growth middle phase are co-cultured according to a certain biomass ratio, so that the anaerobic decolorization efficiency on various azo dye pollutants can be remarkably enhanced. By constructing a symbiotic system based on functional complementation, a new strategy with potential is provided for enhanced removal of azo dye pollution.

The present invention provides a strain of Paracoccus mutans capable of degrading benzo[a]pyrene. The provided Paracoccus mutans strain LYCW-1-6 has a deposit number of CGMCC No. 24841. The Paracoccus mutans provided by the present invention can be used to degrade benzo[a]pyrene. When the benzo[a]pyrene-degrading bacteria is inoculated at a ratio of 2% into a liquid culture medium containing 100 mg / L of benzo[a]pyrene, after 7 days of culture, the benzo[a]pyrene in the culture medium can be degraded by up to 70%. Furthermore, compared to other reported benzo[a]pyrene-degrading bacteria, the strain of the present invention is capable of treating soil or water contaminated with high concentrations of benzo[a]pyrene.

The invention relates to the technical field of aquatic bait culture, in particular to an indoor large-scale amplification culture method for moina mongolica. Comprising the steps that an oxygen pipe, a temperature control pipe and an air stone are arranged in a culture pond, a double-oxygen oxygenation system is placed in the middle, and an incandescent lamp is arranged above; disinfecting and scrubbing facilities in the pool and pool walls with bleaching water; sequentially carrying out rough filtration, fine filtration and ultraviolet disinfection on external seawater, mixing the external seawater with tap water, adjusting the salinity to 15-20, and adding a sodium hypochlorite solution for disinfection; performing detoxification with sodium thiosulfate; screening and expanding germplasm of the moina mongolica by using a 50-60-mesh bolting-silk net; inoculating moina mongolica in the culture water body according to the density of 5500-6500 moina mongolica per liter; environment and water quality parameters are manually regulated and controlled after inoculation; the concentrated nannochloropsis oculata and the yeast are mixed for feeding, and when the daphnia magna density reaches 18000-23000 daphnia magna / L, all the daphnia magna is harvested at a water outlet. The method has the advantages that the daphnia body amplification density is high, and the amplification period is shortened; and pathogenic microorganisms are few.

The invention relates to a complex microbial inoculant for alkali-minimization wastewater treatment as well as a preparation process and application thereof. The complex microbial inoculant is prepared from the following active components in parts by weight: 10 to 12 parts of paracoccus, 9 to 10 parts of hyphomicrobium, 7 to 8 parts of polynematode tarda, 7 to 8 parts of Fabry-Perot, 5 to 6 parts of rope warming bacteria and 2 to 3 parts of spirillum rot. According to the application, a plurality of new strains are formed in the complex microbial inoculant which is cultured by mixing the basic microbial inoculant, the anaerobic sludge, the glucose and the phosphate fertilizer, and the newly generated strains cooperate to enable the complex microbial inoculant to accidentally obtain the performance of efficiently degrading alkali-minimization wastewater pollutants in a high-alkali environment.

The invention discloses a method for preparing PHA (polyhydroxyalkanoate) by using a complex microbial inoculant and application of the PHA. The method for preparing the PHA by using the complex microbial inoculant comprises the following steps: adding the complex microbial inoculant containing flavobacterium into a to-be-fermented liquid, and carrying out aerobic fermentation to obtain a PHA-rich fermented thallus; the liquid to be fermented contains organic acid feed liquid and optional water; the complex microbial inoculant disclosed by the invention comprises neosilurus meridionalis, nitrogen-fixing vibrio, dearomatization bacteria, flavobacterium and paracoccus; the organic acid feed liquid is obtained by performing acid production fermentation on raw materials of enzymatic hydrolysate containing pentose and hexose. According to the present invention, the composite bacterial agent with the high organic acid utilization rate is prepared, and the multiple organic acid fermentation liquids obtained from lignocellulose can be effectively utilized by using the composite bacterial agent so as to perform PHA synthesis, such that the large-scale production of PHA and the resource utilization of lignocellulose are easily achieved.

The application discloses a culture medium for improving production of paracoccus astaxanthin and application thereof. The culture medium comprises the following components according to concentration calculation: yeast extract 4-20 g / L; beef extract 8-20 g / L; bacteriological peptone 4-20 g / L; glucose 10-30 g / L; KH2PO4 0.1-0.2 g / L; Na2HPO4.12H2O 0.1-0.5 g / L; MgSO4.7H2O 0.1-1 g / L; FeSO4.7H2O 0.1-1 g / L; CaCl2.2H2O 0.02-0.1 g / L; and pH 7.2+ / -0.2. In the application, the yeast extract, beef extract and bacteriological peptone are mixed as the nitrogen source, which can promote the accumulation of paracoccus biomass and astaxanthin, and meanwhile, the problem of precipitation after sterilization of the culture medium is solved.

The application provides a composite microbial agent special for sewage denitrification and a carbon source preparation method thereof, and belongs to the technical field of sewage treatment. The composite microbial agent comprises a mixed bacterial solution composed of iron-oxidizing autotrophic denitrifying bacteria, heterotrophic nitrification-aerobic denitrification bacteria and iron mineral mineralization associated bacteria; the iron-oxidizing autotrophic denitrifying bacteria are Paracoccus ferrooxidans, the heterotrophic nitrification-aerobic denitrification bacteria are Pseudomonas stutzeri, and the iron mineral mineralization associated bacteria are Shewanella. The triple coupling system of autotrophic denitrification, heterotrophic denitrification and iron mineral mineralization is constructed, and the industry pain points of insufficient carbon source of low-carbon sewage, poor low-temperature denitrification, easy loss of bacterial strains and high cost of chemical carbon source are solved.

The invention relates to a photosynthetic bacterium recombinant strain with high yield of tocopherol as well as a construction method and application of the photosynthetic bacterium recombinant strain. The photosynthetic bacterium recombinant strain knocks out a photosynthetic gene inhibition transcription factor PpsR of photosynthetic bacteria; a mevalonic acid MEV pathway gene for producing paracoccus zeatin, a p-hydroxyphenylpyruvate dioxidase HPPD gene from pseudomonas putida, a uromelanic acid chlorophyllin transferase HPT gene from synechocystis, a tocopherol cyclase TC gene from arabidopsis thaliana, a recombinant plasmid and a recombinant plasmid are integrated; the invention also discloses a 3-deoxy-D-arabinoheptulose-7-phosphate synthase AroG * D146N gene resistant to feedback and a pre-benzoate dehydrogenase TyrA * M53I gene resistant to feedback. According to the photosynthetic bacterium recombinant strain, efficient heterologous synthesis of tocopherol is achieved by knocking out regulation genes and integrating multi-way metabolism modules, the fermentation yield can reach 3.51 g / L, and the photosynthetic bacterium recombinant strain has wide industrial application prospects.

The invention belongs to the technical field of biological denitrification of aquaculture sewage, and particularly relates to a multi-strain-ceramsite carrier compound for static denitrification purification of aquaculture sewage as well as a preparation method and application of the multi-strain-ceramsite carrier compound. The compound is composed of eight strains of cellulomonas flavigena, bacillus subtillis, bacillus licheniformis, leuconostoc mesenteroides, pediococcus pentosaceus and paracoccus denitrificans, and the eight strains are loaded on a ceramsite carrier through a special process. When the compound disclosed by the invention is used for treating aquaculture sewage, a layered bacterium feeding mode is adopted, and odor can be remarkably inhibited when water is efficiently purified. Practical application results show that after being treated by the compound, the removal rates of total nitrogen, ammonia nitrogen and COD (Chemical Oxygen Demand) in the breeding sewage respectively reach 89.2%, 91.2% and 82.2%. According to the invention, through synergistic interaction of multiple strains, process optimization and accurate regulation and control of spatial distribution, efficient static purification of aquaculture sewage is realized, and an economical and feasible technical path is provided for rural environmental pollution abatement.

The invention provides paracoccus zeaxanthi and application thereof, belongs to the technical field of microorganisms, and particularly relates to paracoccus zeaxanthi QNPS-1, the preservation number of the paracoccus zeaxanthi QNPS-1 is CCTCC NO: M 20253019, the paracoccus zeaxanthi QNPS-1 is preserved in China Center for Type Culture Collection, the address is Wuhan University, Wuhan, China, the preservation date is December 29, 2025, and the preservation number of the paracoccus zeaxanthi QNPS-1 is CCTCC NO: M 20253019. The invention also provides a method for producing the yellow pigment by utilizing the fermentation of the paracoccus zeaxanthin QNPS-1. The yellow pigment produced by the paracoccus zeaxanthin QNPS-1 provided by the invention is good in stability, strong in heat stability and pH stability, and suitable for being applied to various industrial fields.

The invention relates to the technical field of environment-friendly microbial remediation, and particularly discloses a method for constructing a microbiome for organic-heavy metal combined pollution remediation and application of the microbiome, the microbiome comprises Pseudomonas putida, Bacillus cereus, Paracoccus denitrificans and Streptomyces rochei, the number ratio of Pseudomonas putida to Bacillus cereus to Paracoccus denitrificans to Streptomyces rochei is 2: 1: 1: 1, and the construction method comprises the following steps: screening and constructing a functional microbiome to obtain multiple strains; respectively carrying out growth curve determination, gas chromatography or high performance liquid chromatography detection and minimum inhibitory concentration experiment evaluation on the dominant strains, preferably selecting four dominant strains according to experiment results, and constructing a functional microbiome with a synergistic metabolic network; under laboratory conditions, a multi-component mixed culture mode is adopted, co-culture experiments are carried out according to different proportions, the organic matter removal rate, the heavy metal removal rate and flora growth are monitored, and the optimal combination proportion is determined by integrating the results, so that the combined pollution adaptive microbiome is formed; the composite pollution adaptive microbiome is verified through a soil small-scale experiment.

The invention discloses a synthetic flora capable of improving salt tolerance of alfalfa. The synthetic flora consists of a pseudomonas strain EC5, an agrobacterium strain EC17, a streptomyces strain EC15, a paracoccus strain RH39, a pseudomonas strain RH6, a pseudomonas strain RH37, a sporosarcina strain RH34 and a bacillus strain RH32. The synthetic flora provided by the invention has the functions of dissolving organic phosphorus, dissolving inorganic phosphorus, dissolving potassium, producing iron carriers, producing biological membranes, producing IAA and producing ACC deaminase. Seed soaking and germination under the stress of 200 mmol / L and 250 mmol / L NaCl can obviously improve the germination potential, germination rate, germination index, radicle length, germ length and colony seedling embryo fresh weight of alfalfa seeds. Under the stress of 200 mmol / L NaCl, the plant height, stem diameter, leaf area and overground part fresh and dry weight of alfalfa plants can be obviously improved after the seeds are soaked by the synthetic flora.

The invention discloses a composite functional flora for coking wastewater treatment and application thereof, and belongs to the technical field of wastewater treatment. The compound functional flora comprises the following components in percentage by mass: 60-80% of activated sludge flora and 20-40% of compound flora, wherein the activated sludge flora comprises bacillus cereus, pseudomonas putida, acinetobacter radians, paracoccus mutagens and metal-resistant cupriavidus; the composite flora comprises pyridine removal bacteria, aromatic removal bacteria, quinoline removal bacteria, phenol removal bacteria, naphthalene removal bacteria, biological detoxification bacteria, indole removal bacteria, oil removal bacteria and sulfur removal bacteria. According to the present invention, the composite functional flora has good tolerance when the coking wastewater is treated, and has good removal rate on COD, ammonia nitrogen, total nitrogen, cyanide, sulfide, thiocyanide and other organic matters in the coking wastewater, such that the composite functional flora has good application prospects in the coking wastewater treatment.

This invention discloses a strain of *Paragonimus masculinus*, a salt-tolerant growth-promoting bacterial agent, and their applications, belonging to the field of microbial technology. This invention screened a strain of *Paragonimus masculinus* CZJ5 that promotes plant growth and enhances plant salt stress tolerance. It is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 36255. Experimental results show that *Paragonimus masculinus* CZJ5 possesses salt tolerance characteristics and functions such as nitrogen fixation, phosphorus solubilization, silicate solubilization, and siderophore production. It can effectively promote the absorption and utilization of nitrogen, phosphorus, and iron by plants, thereby promoting plant growth. *Paragonimus masculinus* CZJ5 significantly enhances the growth of wild barley plants under salt stress and their salt tolerance. This invention provides a new growth-promoting bacterial agent for improving plant salt tolerance and offers a new technical means for crop cultivation in saline-alkali land.

The application discloses a method for treating high-salt and low-temperature wastewater by using nitrifying bacteria and denitrifying bacteria, and adopts Paracoccus denitrificans TD-20229 screened from ammonia-nitrogen contaminated water bodies to simultaneously and cooperatively ferment wastewater in a high-salt and low-temperature environment together with Alcaligenes faecalis FC-01052. The production strain involved in the application can not only grow in a high-salt and low-temperature wastewater environment, but also has better denitrogenation effect. Compared with traditional physical and chemical denitrogenation methods, the production strain has the problems of low cost and secondary pollution reduction. The application obviously reduces wastewater pollution from the biological denitrogenation technology by using heterotrophic nitrifying bacteria and aerobic denitrifying bacteria, solves the problem of pesticide wastewater treatment in a low-temperature and high-salt environment, and has a wide market prospect.

The invention belongs to the technical field of freeze-drying protection processes of microbial preparations, and discloses a freeze-drying protection method and application of paracoccus verrucosus, by means of the freeze-drying protection method, the freeze-drying survival rate of paracoccus verrucosus is 80.82%, and after the paracoccus verrucosus is stored for 1 month, 6 months and 9 months at 4 DEG C, the survival rates of the paracoccus verrucosus reach 92.07%, 74.13% and 62.80% respectively compared with the survival rates of the paracoccus verrucosus when the paracoccus verrucosus is just freeze-dried. The survival rate is 64.73% after the culture medium is stored at the room temperature of 15-30 DEG C for 30 days, and the culture medium has relatively good heat-resistant stability. According to the freeze-drying protection method provided by the invention, the survival rate of paracoccus verrucosus in the vacuum freeze-drying process can be improved, and the storage life of a freeze-dried sample at the temperature of 4 DEG C and the room temperature is prolonged.

The invention relates to the technical field of enzyme catalysis, and discloses a transaminase mutant obtained by high-throughput screening and application thereof. The parent transaminase of the transaminase mutant is derived from Paracoccus denitrifics PD1222, and the parent transaminase has an amino acid sequence as shown in SEQ ID NO. 1 (Sequence Identifier Number 1). In order to solve the problem of low catalytic activity of current transaminase, the mutant is obtained by performing single-point or multi-point combined substitution on the 19th, 85th, 150th and / or 153rd amino acids in the sequence of SEQ ID NO.1. Preferably, the substitutions include, but are not limited to, F19W, F19L, F19M, F19P, F85M, F85L, Y150M, Y150F, V153S, V153C, V153A and the like. Particularly preferred mutants are combined mutants containing triple substitutions of V153S, F85M and F19W, and the catalytic activity of the mutants on a substrate 1-methoxy-2-acetone is improved by about 12.5 times compared with that of wild type transaminase. The relative enzyme activity of the transaminase mutant provided by the invention is remarkably improved compared with that of a wild type, and the transaminase mutant shows excellent tolerance to a high-concentration substrate.

The invention discloses paracoccus denitrificans, a bacterial agent of the paracoccus denitrificans and application of the paracoccus denitrificans in chemical wastewater treatment, the paracoccus denitrificans is named as PH-21 and preserved in the China General Microbiological Culture Collection Center on March 17, 2025, and the preservation number of the paracoccus denitrificans is CGMCC No. 33832. The invention further discloses a preparation method of the paracoccus denitrificans, and the preparation method of the paracoccus denitrificans and the bacterial agent of the paracoccus denitrificans and the application of the paracoccus denitrificans and the bacterial agent of the paracoccus denitrificans and the application of the paracoccus denitrificans in chemical wastewater treatment. The paracoccus denitrificans PH-21 disclosed by the invention can be used for rapidly degrading 3-pyridine acetate hydrochloride and various organic nitrogen pollutants in wastewater under a high-salt condition (the NaCl concentration is 30g / L) and a low-temperature condition (the water temperature is 8 DEG C), and is excellent in degradation effect and strong in stress resistance.

The invention discloses a paracoccus strain RH39 for improving salt tolerance of alfalfa and application of the paracoccus strain RH39. Wherein the paracoccus strain RH39 is preserved in China General Microbiological Culture Collection Center (CGMCC), the preservation address is No.3, No.1 yard, Beichen West Road, Chaoyang District, Beijing, the preservation date is December 25, 2024, and the preservation number is CGMCC NO.33196. The alfalfa rhizosphere microorganism-paracoccus strain is separated from the alfalfa root in the salinized soil, and has the functions of dissolving organic phosphorus, dissolving inorganic phosphorus, producing a biological membrane, dissolving potassium, producing an IAA membrane and producing ACC deaminase. The germination index of the alfalfa seeds can be obviously improved by soaking the seeds for germination under the stress of 200mmol / L and 250mmol / L NaCl. Under the stress of 200mmol / L NaCl, the growth condition of alfalfa seedlings can be improved.