Paracoccus verrucosus and application thereof

Abstract

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.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of microbial technology, and in particular, to a Paracoccus versutus and application thereof. BACKGROUND

[0002] The capture and conversion of hydrogen sulfide (H2S) has been one of the long-standing economic and environmental challenges. H2S is a highly irritating, foul-smelling and toxic chemical substance, which exists as an impurity in many important fuel gases, such as natural gas, biogas, synthesis gas, coke oven gas, landfill gas, refinery gas, etc., as well as in wastewater streams. H2S forms an acidic solution in the presence of water, leading to corrosion of equipment and pipelines. Its presence also reduces the heating value of fuel gases and causes catalyst poisoning. Most importantly, its combustion leads to the emission of sulfur dioxide and other harmful sulfur oxides, resulting in acid rain. Emissions of H2S must be controlled and limited to improve global atmospheric chemistry and quality of life.

[0003] Biological desulfurization is a green purification technology that uses aerobic and anaerobic bacteria to remove sulfur compounds at normal temperature and pressure. Desulfurization microorganisms absorb metabolic sulfides as their own metabolic nutrients, removing sulfides from the gas to achieve natural gas purification. Compared with pure chemical desulfurization methods, it has incomparable advantages, such as high desulfurization efficiency, simple equipment required, short construction time, low cost, and less chemical consumption.

[0004] The core of biological desulfurization is the selection and use of sulfur-oxidizing bacteria. Sulfur-oxidizing bacteria are one of the main driving forces of the Earth's sulfur cycle. Sulfur-oxidizing bacteria grow and distribute in environments of reduced sulfur compounds such as hydrogen sulfide and elemental sulfur. These microorganisms can use sulfides or sulfur as electron donors and release energy during oxidation to apply to their own growth and metabolism. Sulfur is also an important material for cell structure and plays an important role in signal transmission, redox balance, and gene expression. Sulfur-oxidizing bacteria can be divided into photoautotrophs and chemotrophs according to their metabolic modes.

[0005] Photoautotrophic sulfur-oxidizing bacteria rely on the absorption of photons to obtain energy to maintain metabolism. However, photoautotrophic sulfur-oxidizing bacteria need to be continuously provided with light during the metabolic process. During the process of sulfur discharge outside the bacteria, the turbidity of the solution system reduces the utilization rate of light, which prevents photoautotrophic sulfur-oxidizing bacteria from achieving stable operation of biological desulfurization, and also limits their application.

[0006] The bacteria currently used in the field of biological desulfurization are chemotrophic sulfur-oxidizing bacteria. Chemotrophic sulfur-oxidizing bacteria include aerobic and anaerobic types. The aerobic sulfur-oxidizing bacteria use O2 as the electron acceptor, and the anaerobic sulfur-oxidizing bacteria use nitrate or nitrite as the electron acceptor. These microorganisms use H2S as energy and CO2 as carbon source. However, the current bacteria still have problems of low desulfurization efficiency and low sulfur generation rate. For example, a strain of Bacillus cereus S5 for degrading hydrogen sulfide described in patent CN 114874938A has a hydrogen sulfide degradation rate of 74.6% in 48h, and has a low desulfurization rate and a low sulfur generation rate. The desulfurization efficiency of microorganisms limits the application of biological desulfurization.

[0007] Therefore, the present application is proposed. SUMMARY

[0008] The existing problems of the prior art are that the current desulfurization bacteria have low sulfur oxidation capacity and sulfur conversion rate, and the slow reproduction of the bacteria limits its application to some extent. The present application provides a Paracoccus versutus and its application, which has strong desulfurization capacity and high sulfur conversion rate, and has good application potential in biological desulfurization.

[0009] The present application is realized by the following technical solutions:

[0010] In a first aspect, the present application provides a sulfur-oxidizing bacterium-Paracoccus versutus, which is Paracoccus versutus TYWJ-2, with a preservation number of CGMCC No.31068, and is preserved in the General Microbiological Center of the Chinese Microorganism Bacterium Preservation Management Committee on June 24, 2024. The address is No.3, Beichen West Road, Yard 1, Chaoyang District, Beijing, China, and the post code is 100101.

[0011] The Paracoccus versutus TYWJ-2 provided by the present application has strong desulfurization capacity and high sulfur conversion rate, with a sulfide degradation rate of 98.1% in 12h and a sulfur generation rate of 76.8%.

[0012] The Paracoccus versutus TYWJ-2 (CGMCC No.31068) provided by the present application is separated from a high-salinity wastewater pool in the Wanxian Branch Plant of the General Plant of the Natural Gas Purification Branch Company of PetroChina Southwest Oil and Gas Field Company. The separation method comprises the following steps:

[0013] (1) Take 10mL of high-salinity wastewater in a 250mL conical flask, add 100mL of normal saline, and shake on a shaker for 12h at a temperature of 35℃ and a speed of 120rpm;

[0014] (2) Take 20 mL supernatant in 80 mL sodium thiosulfate liquid medium, and enrich culture for 1 week. After 1 week, take the culture liquid to inoculate fresh sodium thiosulfate medium at a proportion of 20%, and the process is enriched for 3 times;

[0015] (3) Take 200 μL of the culture liquid after enrichment, and perform plate coating culture using sodium sulfide inorganic solid medium. After sealing, place in a culture box to culture in the dark; culture conditions: temperature 35°C, humidity 80%;

[0016] (4) After 2 days, when colonies grow, use a loop to pick a small amount of bacteria, and perform streak separation in sodium sulfide inorganic medium. The process is repeated for 6-8 times to obtain pure bacteria, and the bacteria are named as TYWJ-2.

[0017] The sodium thiosulfate liquid medium comprises:

[0018] A liquid: 7.85 g / L Na2S2O3.5H2O is dissolved in 20 mL deionized water;

[0019] B liquid: 1.5 g NaHCO3, 2.0 g KNO3, 2.0 g KH2PO4, 1.0 g NH4Cl, 0.15 g MgSO4.7H2O, and 2 mL trace element solution are dissolved in 980 mL deionized water.

[0020] The configuration method is that the B liquid is adjusted to pH 7 by using 0.5M NaOH aqueous solution, high-temperature sterilization is performed at 120°C for 30 min, and the ultraviolet sterilized A liquid is added.

[0021] The sodium sulfide liquid medium comprises:

[0022] A liquid: 10.0 g Na2S.9H2O is dissolved in 20 mL deionized water;

[0023] B liquid: 1.5 g NaHCO3, 2.0 g KH2PO4, 1.0 g NH4Cl, 0.15 g MgSO4.7H2O, and 2 mL trace element solution are dissolved in 980 mL deionized water.

[0024] The configuration method is that the B liquid is adjusted to pH 7 by using 0.5M hydrochloric acid, high-temperature sterilization is performed at 120°C for 30 min, and the ultraviolet sterilized A liquid is added.

[0025] The sodium sulfide solid medium is formed by adding 2%-2.5% agarose with a mass fraction to the sodium sulfide liquid medium, dissolving, and then cooling to form a plate.

[0026] The trace element solution in the sodium thiosulfate culture medium and the sodium sulfide culture medium includes the following components per liter: ZnCl240 mg, FeCl3·6H2O 200 mg, CaCl2·2H2O 10 mg, MnCl2·4H2O 10 mg, Na2B4O7·10H2O 10 mg, (NH4)6Mo7O 24 ·4H2O 10 mg.

[0027] The Paracoccus versutus TYWJ-2 has the following physiological characteristics: ellipsoidal shape, about 0.8-1.3 μm long, 0.5-0.8 μm wide, gram-negative bacteria, and round and convex colony morphology with a milky white color. It can grow normally under the conditions of pH 5.0-9.0, and the optimal growth pH range is 7.0-8.0. The growth temperature is 10-40°C, preferably 25-35°C. The microorganism is inorganic nutrition type, and can grow in an inorganic culture medium with sodium sulfide as the only sulfur source and sodium bicarbonate as the only carbon source.

[0028] In a specific embodiment, the nucleotide sequence of the Paracoccus versutus TYWJ-2 is shown in SEQ ID NO: 1.

[0029] In a second aspect, the present application provides an application of Paracoccus versutus for biological desulfurization.

[0030] In a specific embodiment, the Paracoccus versutus is used for converting S 2- to elemental S, S2O3 2- and / or SO4 2- .

[0031] In a specific embodiment, the Paracoccus versutus is used for biological desulfurization of natural gas or biogas.

[0032] In a specific embodiment, the specific steps of the Paracoccus versutus for desulfurization are as follows:

[0033] Under sterile conditions, the Paracoccus versutus TYWJ-2 is inoculated into a Na2S2O3 culture medium for culture, constant temperature and shock culture, the bacterial liquid after culture is centrifuged, and the supernatant is added into an inorganic culture medium containing S 2- for desulfurization reaction.

[0034] In a specific embodiment, the specific components of the inorganic culture medium are as follows: Na2S2O3·5H2O 7.85 g / L, NaHCO3 1.5 g / L, KNO3 2.0 g / L, KH2PO4 2.0 g / L, NH4Cl 1.0 g / L, MgSO4·7H2O 0.15 g / L, and trace element solution 2 mL / L.

[0035] The trace element solution in the sodium thiosulfate inorganic culture medium includes: ZnCl240 mg, FeCl3·6H2O 200 mg, CaCl2·2H2O 10 mg, MnCl2·4H2O 10 mg, Na2B4O7·10H2O 10 mg, (NH4)6Mo7O 24 ·4H2O 10 mg.

[0036] In a specific embodiment, the culture conditions for Paracoccus versutus TYWJ-2 are: pH = 5-9, preferably pH = 7-8, temperature 10-40℃, preferably 25-35℃, 150 rpm shaking culture; in the desulfurization reaction, the OD 600 of the reaction culture medium is 0.350, pH = 5-9, preferably pH = 7-8, temperature 10-40℃, preferably 25-35℃, rotation speed 150 rpm, aeration amount 0.5 L / min.

[0037] In a specific embodiment, the Paracoccus versutus is used for preparing a biological desulfurizer.

[0038] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0039] 1. The Paracoccus versutus and its application provided by the embodiment of the present application are screened from a high-salt wastewater pool rich in sulfides in a natural gas purification plant, the microorganism is non-pathogenic and will not affect the human body and the ecological environment;

[0040] 2. The Paracoccus versutus and its application provided by the embodiment of the present application have a faster desulfurization rate, under the condition of an inorganic culture medium, when the initial OD value of the bacterial solution is 0.339 and the initial S 2- concentration is 355.2 mg / L, 98.1% of sulfides can be removed within 12 h, and the highest sulfur generation rate is 76.8%. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present application, the drawings needed in the embodiments will be briefly introduced as follows, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and other related drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0042] Figure 1 The picture of the sewage sample collection site provided by the embodiment of the present application;

[0043] Figure 2 The microscope picture of Paracoccus versutus TYWJ-2 provided by the embodiment of the present application, scale 10 μm;

[0044] Figure 3 The growth curve of Paracoccus versutus TYWJ-2 in a sodium sulfide culture medium provided for the embodiments of the present application;

[0045] Figure 4 The growth curve of Paracoccus versutus TYWJ-2 in a sodium thiosulfate culture medium provided for the embodiments of the present application;

[0046] Figure 5 The growth curve of Paracoccus versutus TYWJ-2 in a sodium thiosulfate culture medium with different pH provided for the embodiments of the present application;

[0047] Figure 6 The ion concentration of sulfur ions, sulfur, thiosulfate and sulfate at different time points in the desulfurization tank test of Paracoccus versutus TYWJ-2 provided for the embodiments of the present application. DETAILED DESCRIPTION

[0048] In order to make the objects, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application in combination with embodiments and drawings, and the schematic embodiments of the present application and the description thereof are only used to explain the present application, and not as a limitation to the present application.

[0049] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without these specific details. In other instances, well-known materials or methods have not been described in detail in order to avoid obscuring the present application.

[0050] Throughout the specification, the mention of “one embodiment,” “an embodiment,” “one example,” or “an example” means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the application. Therefore, the appearance of the phrases “in one embodiment,” “in an embodiment,” “in one example,” or “in an example” at various places in the specification is not necessarily referring to the same embodiment or example. Furthermore, particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments or examples. Moreover, one of ordinary skill in the art will appreciate that the diagrams provided herein are for illustrative purposes only and are not necessarily drawn to scale. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0051] In the description of this invention, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0052] Currently, the most widely used microbial strains in the field of biological desulfurization are chemoautotrophic sulfur-oxidizing bacteria. Chemoautotrophic sulfur-oxidizing bacteria include aerobic and anaerobic types. Aerobic sulfur-oxidizing bacteria use O2 as the electron acceptor, while anaerobic sulfur-oxidizing bacteria use nitrate or nitrite as the electron acceptor. These microorganisms use H2S as their energy source and CO2 as their carbon source. However, current strains still suffer from low desulfurization efficiency and low sulfur formation rate.

[0053] To solve the above problems, the present invention is achieved through the following technical solution:

[0054] In a first aspect, the present invention provides a sulfur-oxidizing bacterium, Paracoccus versutus, wherein the Paracoccus versutus is Paracoccus versutus TYWJ-2, with accession number CGMCC No. 31068, which was deposited on June 24, 2024, at the China General Microbiological Culture Collection Center; the address is No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, postcode: 100101.

[0055] The *Paragonimus westermani* TYWJ-2 provided by this invention has strong desulfurization ability and high sulfur conversion rate. The sulfide degradation rate reaches 98.1% and the sulfur generation rate reaches 76.8% in 12 hours.

[0056] The *Paracoccus versutus* TYWJ-2 (CGMCC No. 31068) provided by this invention was isolated from a high-salt wastewater pond at the Wanzhou branch of the Natural Gas Purification Plant of the Southwest Oil and Gas Field Company of China National Petroleum Corporation. The physiological characteristics of *Paracoccus versutus* TYWJ-2 are as follows: elliptical morphology, approximately 0.8–1.3 μm long and 0.5–0.8 μm wide; Gram-negative; colony morphology: round, convex; milky white color. It can grow normally under pH conditions from 5.0 to 9.0, with an optimal growth pH range of 7.0–8.0. The growth temperature is 10–40℃, preferably 25–35℃. This microorganism is an inorganic nutrient type and can grow in an inorganic culture medium with sodium sulfide as the sole sulfur source and sodium bicarbonate as the sole carbon source.

[0057] Secondly, the present invention provides an application of *Paragonimus westermani* for biological desulfurization.

[0058] In one specific implementation, S is used to... 2- Oxidized to elemental S and S2O3 2- and / or SO4 2- .

[0059] In one specific implementation, it is used for biological desulfurization of natural gas or biogas.

[0060] In one specific embodiment, the specific steps for using the variable paracoccus for desulfurization are as follows:

[0061] Under aseptic conditions, *Paragonimus westermani* TYWJ-2 was inoculated into Na2S2O3 medium and cultured under constant temperature and shaking. The cultured bacterial solution was centrifuged, and the supernatant was added to a medium containing S... 2- The desulfurization reaction can be carried out in an inorganic culture medium.

[0062] In one specific embodiment, the culture conditions for culturing *Paragonimus westermani* TYWJ-2 are: pH = 5–9, preferably pH = 7–8, temperature 10–40°C, preferably 25–35°C, and shaking culture at 150 rpm; in the desulfurization reaction, the OD in the reaction medium... 600 The pH value is 0.350, pH = 5-9, preferably pH = 7-8, temperature is 10-40℃, preferably 25-35℃, rotation speed is 150 rpm, and aeration rate is 0.5 L / min.

[0063] In one specific embodiment, the *Paragonimus westermani* is used to prepare a biological desulfurizing agent.

[0064] Example 1

[0065] This invention provides a screening method for the variable paracoccus TYWJ-2, as detailed below:

[0066] Wastewater samples were collected from the high-salinity wastewater pool of the Wanzhou branch of the Natural Gas Purification Plant of the Southwest Oil and Gas Field Company. Figure 1 As shown.

[0067] The separation method is as follows:

[0068] (1) Take 10 mL of high-salt wastewater into a 250 mL conical flask, add 100 mL of physiological saline, shake on a shaker for 12 h at a temperature of 35 °C and a rotation speed of 120 rpm.

[0069] (2) After standing, take 20 mL of the supernatant and put it into 80 mL of sodium thiosulfate liquid culture medium. Enrich and culture for 1 week. After 1 week, take the culture medium and inoculate it into fresh sodium thiosulfate culture medium at a ratio of 20%. This process is repeated 3 times.

[0070] (3) Take 200 μL of the enriched culture medium and plate it using sodium sulfide inorganic solid culture medium. After sealing, place it in an incubator in the dark. Culture conditions: temperature 35℃, humidity 80%;

[0071] (4) After waiting for 2 days for the colonies to grow, pick up a small amount of the inoculum with an inoculation loop and streak it in sodium sulfide inorganic medium. Repeat this process 6 to 8 times to obtain pure bacteria. Name the bacteria TYWJ-2.

[0072] The components of the sodium thiosulfate liquid culture medium are as follows:

[0073] Solution A: Na₂S₂O₃·5H₂O 7.85 g / L dissolved in 20 mL of deionized water;

[0074] Solution B: 1.5g NaHCO3, 2.0g KNO3, 2.0g KH2PO4, 1.0g NH4Cl, 0.15g MgSO4·7H2O, and 2mL of trace element solution dissolved in 980mL deionized water.

[0075] The preparation method is as follows: adjust the pH of solution B to 7 with 0.5M NaOH aqueous solution, sterilize at 120℃ for 30 minutes, and then add solution A which has been sterilized by ultraviolet light.

[0076] The components of the sodium sulfide liquid culture medium are as follows:

[0077] Solution A: 10.0 g of Na₂S·9H₂O dissolved in 20 mL of deionized water;

[0078] Solution B: 1.5g NaHCO3, 2.0g KH2PO4, 1.0g NH4Cl, 0.15g MgSO4·7H2O, and 2mL of trace element solution dissolved in 980mL deionized water.

[0079] The preparation method is as follows: adjust the pH of solution B to 7 with 0.5M hydrochloric acid, sterilize at 120℃ for 30 minutes, and then add solution A which has been sterilized by ultraviolet light.

[0080] Sodium sulfide solid culture medium is prepared by adding 2% to 2.5% agarose by mass to sodium sulfide liquid culture medium, dissolving and then cooling to form plates.

[0081] The trace element solutions in the sodium thiosulfate and sodium sulfide culture media each contain: ZnCl2 40 mg, FeCl3·6H2O 200 mg, CaCl2·2H2O 10 mg, MnCl2·4H2O 10 mg, Na2B4O7·10H2O 10 mg, (NH4)6Mo7O 24 ·4H2O 10mg.

[0082] like Figure 2 As shown, the Gram staining result of Paracoccus TYWJ-2 was negative. The morphology was ellipsoidal, about 0.8-1.3 μm long and 0.5-0.8 μm wide.

[0083] Example 2

[0084] This invention provides a molecular biological identification of the strain of Paracoccus TYWJ-2, comprising the following steps:

[0085] (1) Prepare bacterial lysis buffer

[0086] 1μL 0.2mol / L NaOH, 2.5μL 1% SDS.

[0087] (2) Genomic DNA extraction

[0088] Take 5 μL of bacterial lysate into a 1.5 mL centrifuge tube, and add a certain amount of the bacterial precipitate to be tested into the centrifuge tube. Mix well (be careful to avoid a large number of bubbles) and react for 5 min. Add 200 μL of dd H2O to stop the reaction (mix well).

[0089] (3) Genomic PCR amplification

[0090] Primer sequence: 27F: 5'-AGAGTTTGATCCTGGCTCAG-3'

[0091] 1492R:5'-GGTTACCTTGTTACGACTT-3'

[0092] PCR reaction conditions: pre-denaturation 94℃, 3 min;

[0093] Denaturation at 94℃ for 45 seconds, annealing at 58℃ for 45 seconds, extension at 72℃ for 2 minutes, 30 cycles;

[0094] Extend the time to 72℃ for 10 minutes.

[0095] (4) Gene sequencing

[0096] This experiment used the Sanger method to sequence PCR products. First, unidirectional primer sequencing was performed. If there were no overlapping peaks in the unidirectional sequencing, the other end of the sequence was detected. The sequencing results were spliced ​​using DNAMAN software.

[0097] (5) Appraisal results

[0098] The 16S rDNA sequence of *Paragonimus westermani* TYWJ-2, SEQ ID NO: 1, is as follows:

[0099]

[0100] After comparison with NCBI, the strain showed a 99% similarity to Paracoccus versutus ATCC 25364, which was discovered in Texas soil in 1969. Therefore, its Chinese name is Paracoccus versutus TYWJ-2.

[0101] Example 3

[0102] This invention provides a method for determining the growth curve of *Paragonimus westermani* TYWJ-2, comprising the following steps:

[0103] (1) Pick up TYWJ-2 colonies on the plate with an inoculation loop and place them in sodium thiosulfate medium. Incubate for 48 hours to obtain a high concentration of bacterial solution. Inoculate the bacterial solution into sodium sulfide medium and sodium thiosulfate medium at a ratio of 10%.

[0104] (2) Regularly detect bacterial culture OD 600 The values ​​were used to obtain the growth curves of Paracoccus TYWJ-2 in different culture media.

[0105] like Figure 3 As shown, when *Paragonimus westermani* TYWJ-2 uses sodium sulfide as the sole sulfur source and sodium bicarbonate as the sole carbon source, it enters the logarithmic growth phase in 2-10 hours, and its OD... 600 It rose from 0.188 to 0.365, and then entered a stable period. OD 600 It eventually stabilized at around 0.4, and the bacterial concentration no longer increased.

[0106] like Figure 4 As shown, *Paragonimus westermani* TYWJ-2 enters the logarithmic growth phase in 4-24 hours when sodium thiosulfate is the sole sulfur source and sodium bicarbonate is the sole carbon source. 600 The value rose from 0.195 to 0.293, then entered a period of slow growth, eventually reaching OD. 600 It stabilized at around 0.36.

[0107] Example 4

[0108] This invention provides an embodiment for determining the optimal pH for *Paragonimus westermani* TYWJ-2, comprising the following steps:

[0109] Take 200 mL of sodium thiosulfate culture medium into a 500 mL Erlenmeyer flask, adjust the pH to 5, 6, 7, 8, and 9 respectively with 1 M NaOH aqueous solution or 1 M hydrochloric acid solution, and inoculate TYWJ-2 bacterial suspension cultured in sodium thiosulfate medium in the logarithmic growth phase at an inoculum volume of 20%.

[0110] like Figure 5As shown, Paracoccus TYWJ-2 can grow under conditions of pH 5 to 9, with the optimal pH being 7 to 8.

[0111] Example 5

[0112] This invention provides a desulfurization test on *Paragonimus westermani* TYWJ-2, comprising the following steps:

[0113] (1) A desulfurization test of Paracoccus TYWJ-2 was conducted using an Eppendorf BioFlo / CelliGen110 bio-fermenter (2L);

[0114] (2) TYWJ-2 was cultured in 1800 mL of sodium sulfide medium in a tank, and the OD of the medium was measured. 600 The value is 0.339, the temperature is set at 35℃, the rotation speed is 150rpm, and the aeration rate is 0.5L / min (sterile air);

[0115] (3) Add 6.1g of sodium sulfide nonahydrate to the tank to make the solution S 2- The concentration was 400 mg / L (actually measured 355.5 mg / L), and samples were taken every 2 hours to detect S in the solution. 2- Sulfur, S2O3 2- and SO4 2- The concentration;

[0116] (4)S 2- The detection methods employed included the methylene blue assay, sulfur content was determined using the law of conservation of mass, and S2O3... 2- Iodometric titration was used for detection, and sulfate ions were detected using the Hach sulfate detection kit (2106769-CN).

[0117] like Figure 6 As shown, in the desulfurization tank test of *Paragonimus westermani* TYWJ-2, with an initial concentration of 355.5 mg / L, 94.2% of sulfur was removed after 8 hours. 2- 12h S 2- The removal rate reached 98.1%. During the desulfurization process, the sulfur concentration increased, and the sulfate concentration also increased. The thiosulfate concentration increased slightly, indicating that some sulfur ions were metabolized into thiosulfate and sulfate. The sulfur formation rate was highest at 8 hours, reaching 76.8%.

[0118] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A variable paracoccus, characterized in that, The Paracoccus versutus mentioned is Paracoccus versutus TYWJ-2, with accession number CGMCC No.31068, which was deposited at the China General Microbiological Culture Collection Center on June 24, 2024.

2. The *Paragonimus westermani* according to claim 1, characterized in that, The nucleotide sequence of the paracoccus TYWJ-2 is shown in SEQ ID NO:

1.

3. An application of *Paragonimus westermani* as described in claim 1, characterized in that, Used for biological desulfurization.

4. The application of *Paragonimus westermani* according to claim 3, characterized in that, Used to transfer S 2- Oxidized to elemental S and S2O3 2- and / or SO4 2- .

5. The application of *Paragonimus westermani* according to claim 3, characterized in that, Biological desulfurization for natural gas or biogas.

6. The application of *Paragonimus westermani* according to claim 3, characterized in that, The specific steps for using the variable paracoccus in desulfurization are as follows: Under aseptic conditions, *Paragonimus westermani* TYWJ-2 was inoculated onto Na2. S Cultured in 2O3 medium with constant temperature and shaking, the cultured bacterial solution was centrifuged, and the supernatant was added with S. 2- The desulfurization reaction can be carried out in an inorganic culture medium.

7. The application of *Paragonimus westermani* according to claim 6, characterized in that, The specific components of the inorganic culture medium are: Na2S2O3·5H2O 7.85g / L, NaHCO3 1.5g / L, KNO3 2.0g / L, KH2PO4 2.0g / L, NH4Cl 1.0g / L, MgSO4·7H2O 0.15g / L, and trace element solution 2mL / L.

8. The application of *Paragonimus westermani* according to claim 6, characterized in that, The culture conditions for Paracoccus TYWJ-2 were: pH 5–9, temperature 10–40℃, and shaking culture at 150 rpm.

9. The application of *Paragonimus westermani* according to claim 6, characterized in that, In the desulfurization reaction, the OD in the reaction medium 600 The aeration rate was 0.339, pH = 5-9, temperature 10-40℃, rotation speed 150rpm, and aeration rate 0.5L / min.

10. The application of *Paragonimus westermani* according to claim 3, characterized in that, Used in the preparation of biological desulfurizing agents.

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