Bacteria capable of accumulating heavy metals and use thereof

Abstract

The present application relates to the technical field of microbial application, and specifically discloses a kind of bacteria that can enrich heavy metals and application thereof, wherein the strain is preserved in China General Microbiological Culture Collection Center on September 26, 2022, and the strain preservation number is CGMCC No.25796.The bacteria Sinirhodobacter sp.1C5-22 provided by the present application can effectively enrich Cd 2+ , Ni 2+ , Cu 2+ and Zn 2+ in solution, with removal rates of more than 50% in 10mg / L Cd 2+ , Ni 2+ , Cu 2+ solution, which lays a foundation for studying the use of Sinirhodobacter sp.1C5-22 for remediation in cadmium, nickel, copper and zinc contaminated environments, enriches the microbial library for remediation of heavy metal pollution using microorganisms, and provides technical support for ultimately using microorganisms to remediate water and soil heavy metal pollution.

Description

Technical Field

[0001] This invention relates to the field of microbial applications, and more particularly to a bacterium capable of accumulating heavy metals and its applications. Background Technology

[0002] Heavy metal pollution is increasingly becoming a concern. Due to rapid agricultural and metal industry development, improper waste disposal, and the use of fertilizers and pesticides, these inorganic pollutants are being dumped into waterways, soil, and the atmosphere. Heavy metal pollution not only severely impacts the ecological environment but also poses certain risks to human health. Currently, heavy metal pollution has become a major problem seriously affecting human health and environmental safety. Traditional methods for treating heavy metal pollution are mostly physicochemical methods, such as chemical precipitation, ion exchange, reverse osmosis, and activated carbon adsorption. While each has its advantages, they all suffer from varying degrees of complexity, high cost, high energy consumption, and the potential for secondary pollution.

[0003] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a bacterium that can enrich heavy metals and its application, aiming to solve the problems of existing methods for treating heavy metal pollution, which are complex to varying degrees, costly, energy-intensive, and prone to secondary pollution.

[0005] The technical solution of the present invention is as follows:

[0006] A bacterium capable of accumulating heavy metals, wherein the bacterium belongs to the genus *Sinorhodobacter* and is named *Sinirhodobacter* sp. 1C5-22. This strain was deposited on September 26, 2022, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 25796.

[0007] The bacteria capable of accumulating heavy metals, wherein the heavy metals include cadmium, nickel, copper, and zinc.

[0008] The bacteria capable of accumulating heavy metals, wherein the bacteria are present in environments containing the heavy metal Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ Grown in liquid culture medium, for Cd 2+ Ni 2+ Cu 2+ and Zn 2+ The tolerability levels were 20 mg / L, 500 mg / L, 600 mg / L, and 600 mg / L, respectively.

[0009] The bacteria capable of accumulating heavy metals, wherein the actinomycetes are present in a solution containing 10 mg / L Cd. 2+ When cultured in solution, for Cd 2+ The removal rate reached 67.91%, and the enrichment amount was 5.79 mg / g.

[0010] The bacteria capable of accumulating heavy metals, wherein the bacteria are present in a Ni concentration of 10 mg / L. 2+ When cultured in solution, for Ni 2 + The removal rate reached 70.09%, and the enrichment amount was 5.90 mg / g.

[0011] The bacteria capable of accumulating heavy metals, wherein the bacteria are present in a Cu concentration of 10 mg / L. 2+ When culturing in solution, for Cu 2 + The removal rate reached 75.17%, and the enrichment amount was 7.69 mg / g.

[0012] The bacteria capable of accumulating heavy metals, wherein the bacteria are present in a solution containing 10 mg / L Zn. 2+ When cultured in solution, for Zn 2 + The removal rate reached 40.14%, and the enrichment amount was 3.59 mg / g.

[0013] An application of a bacterium capable of enriching heavy metals as described in this invention, wherein the bacterium is used to enrich cadmium, nickel, copper and zinc.

[0014] An application of bacteria capable of enriching heavy metals as described in this invention, wherein the bacteria are immobilized to form a bacterial agent for enriching cadmium, nickel, copper, and zinc.

[0015] Beneficial effects: This invention first screened bacteria with heavy metal tolerance from surface soil samples of the Shenzhen Futian Mangrove Nature Reserve. Through 16S rRNA sequence alignment, ANI value calculated from whole-genome sequencing, and DNA-DNA hybridization value, a potential new bacterium within the genus *Sinirhodobacter* was discovered, preliminarily identified as *Sinirhodobacter* sp. 1C5-22. The bacterium *Sinirhodobacter* sp. 1C5-22 described in this invention can effectively enrich Cd in solution. 2+ Ni 2+ Cu 2+ and Zn 2+ At 10 mg / L Cd 2+ Ni 2+ Cu 2+The removal rates in the solutions all exceeded 50%, suggesting that *Sinirhodobacter* sp. 1C5-22 has potential remediation effects in environments contaminated with cadmium, nickel, and copper. The *Sinirhodobacter* sp. 1C5-22 bacteria described in this invention can produce a large amount of microbial biomass through rapid fermentation. The resulting microbial agent is commercially viable, low-cost, simple to operate, recyclable, environmentally friendly, and highly efficient, facilitating the removal of Cd from polluted water. 2+ Ni 2+ Cu 2+ and Zn 2+ This invention provides greater possibilities and operability; the microbial agent prepared by immobilizing Sinirhodobacter sp. 1C5-22 can achieve better metal ion removal effect compared with unimmobilized strains, at 10 mg / L Ni 2+ Cu 2+ The removal efficiency in solution reaches over 90%, and it is effective even at 10 mg / L Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The enrichment levels in the solution were significantly higher than those of the unimmobilized strains, suggesting that the immobilized microbial agent has a better enrichment effect in actual heavy metal-contaminated wastewater compared to a single strain. This study investigated the tolerance of heavy metal Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The bacteria Sinirhodobacter sp. 1C5-22 growing in solution Cd 2+ Ni 2+ Cu 2+ and Zn 2+ The enrichment capacity of Sinirhodobacter sp.1C5-22 lays the foundation for research on the remediation of cadmium, nickel, copper and zinc polluted environments, enriches the microbial library for the remediation of heavy metal pollution by microorganisms, and provides technical support for the ultimate realization of the remediation of heavy metal pollution in water and soil by microorganisms. Attached Figure Description

[0016] Figure 1 A frontal plate colony photograph of Sinirhodobacter sp.1C5-22, a bacterium capable of accumulating heavy metals, provided for this invention.

[0017] Figure 2 This is a schematic diagram of the microbial inoculant prepared by immobilizing Sinirhodobacter sp.1C5-22.

[0018] Figure 3 Sinirhodobacter sp. 1C5-22, immobilization carrier, and immobilized Sinirhodobacter sp. 1C5-22 in heavy metal concentrations of 10 mg / L Cd 2+ Ni 2+ Cu 2+ and Zn 2+ A graph showing the relationship between the removal rate of metal ions in the environment.

[0019] Figure 4 Sinirhodobacter sp. 1C5-22, immobilization carrier, and immobilized Sinirhodobacter sp. 1C5-22 in heavy metal concentrations of 50 mg / L d. 2+ Ni 2+ Cu 2+ and Zn 2+ A graph showing the relationship between the removal rate of metal ions in the environment.

[0020] Figure 5 Sinirhodobacter sp. 1C5-22, immobilization carrier, and immobilized Sinirhodobacter sp. 1C5-22 in heavy metal concentrations of 10 mg / L Cd 2+ Ni 2+ Cu 2+ and Zn 2+ A graph showing the relationship between the amount of metal ions adsorbed in the environment. Detailed Implementation

[0021] This invention provides a bacterium capable of accumulating heavy metals and its applications. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] Microbial remediation is a promising method for treating heavy metal pollution. It utilizes certain soil microorganisms that can absorb, precipitate, oxidize, and reduce heavy metals, thereby reducing their toxicity in the polluted environment. It not only provides rapid remediation but also has minimal impact on the surrounding environment, avoiding secondary pollution. Bioaccumulation using growing cells is an important technique in microbial remediation. Growing cells are self-sufficient and, after physical adsorption, can continue to metabolize and absorb metals. Metals dispersed within the cells enter vacuoles and other cellular structures, where they chelate with intracellular proteins. These processes are typically irreversible.

[0023] Generally, soil microorganisms are easily affected by metal pollutants, leading to a decline in microbial population density or even extinction. However, microorganisms are highly environment-specific, exhibiting different morphological structures and functions depending on the environment. From the perspective of biological evolution, survival of the fittest means that microorganisms can survive in environments polluted by heavy metals and develop a certain degree of tolerance, gradually becoming the dominant species in the soil, and even utilizing heavy metals to complete certain physiological activities.

[0024] Mangroves are transitional ecosystems between land and sea, rich in biological resources. Due to their unique geographical location, they have long suffered from seawater erosion and wave impact. The extensive root systems of mangrove plants mitigate the tidal erosion effect while promoting particulate matter deposition. As a natural barrier of the coastline, mangroves accumulate large amounts of pollutants from human activities, with heavy metals being one of the most significant pollutants. A large number of microorganisms exist in heavy metal environments. Microorganisms are highly sensitive to environmental changes; populations of microorganisms that cannot adapt to heavy metal environments decline or even become extinct. However, some microorganisms possess a certain degree of resistance to heavy metal toxicity, surviving and developing tolerance in heavily polluted environments. They gradually become dominant populations in the soil, thus providing an ideal environment for cultivating heavy metal-tolerant microorganisms.

[0025] Based on this, the present invention provides a bacterium belonging to the genus *Sinirhodobacter* that can accumulate heavy metals, selected from the Shenzhen Futian Mangrove Nature Reserve, named *Sinirhodobacter* sp.1C5-22. This strain was deposited at the China General Microbiological Culture Collection Center on September 26, 2022, with the culture accession number CGMCC No.25796.

[0026] Specifically, samples were collected at the tidal flats of the Shenzhen Futian Mangrove Nature Reserve (longitude 144°00′, latitude 22°31′, geodetic height -3.9792cm), quickly placed in sterile bags, placed on ice, and transported back to the laboratory for storage at 4°C.

[0027] The traditional plate culture method was used to screen strains: First, the sample was mixed with sterile water and shaken well, and then serially diluted. 100 μL of the diluted solution was then plated onto a plate containing Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ On R2A solid medium, glass beads were added and the mixture was shaken in a cross shape in a clean bench to ensure the diluted solution was evenly distributed on the medium. The growth of colonies was observed daily. Colonies with different colors and morphologies were isolated and inoculated into fresh medium for purification culture to obtain the desired results. Figure 1The colony diagram shown is as follows. On the culture medium, the colonies are observed to be white and translucent, small, round, with a smooth surface and a raised center, and the texture of the colonies is uniform.

[0028] DNA was extracted from the strain using the Tiangen reagent kit, and the microorganisms were identified based on 16S rRNA sequence analysis. Amplification was performed using universal primers 27F (5′-AGAGTTTGATCMTGGCTCAG-3′) and 1492R (5′-TACGGYTACCTTGTTACGACTT-3′). PCR was performed in a 20 μL volume containing 1 μL template DNA, 0.5 μL each of forward and reverse primers, 10 μL Taq-DAN polymerase, and 8 μL ddH2O. The PCR program was as follows: pre-denaturation at 95℃ for 5 min, followed by 32 cycles of denaturation at 95℃ for 30 s; annealing at 59℃ for 30 s; extension at 72℃ for 2 min; and further extension at 72℃ for 5 min. The sample was then stored at 4℃. The PCR products were detected by 1.0% agarose gel electrophoresis and sequenced using an ABI 3730xl automated DNA sequencer. The results were submitted to the NCBI nucleotide database and compared with nucleotide sequences in GenBank to determine the species. The extracted strain was finally identified as belonging to the genus *Sinirhodobacter*, and the strain was named *Sinirhodobacter sp.1C5-22*.

[0029] Furthermore, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium, and then single colonies were picked and cultured in MB liquid medium at 35°C, 200 rpm, and 35°C in a shaker. When the seed culture reached the logarithmic growth phase, 0.05% inoculum was added to 96-well plates containing pre-prepared Cd gradients. 2+ Ni 2+ Cu 2+ and Zn 2+ In MB liquid culture medium, the bacteria were shaken and cultured for 3 days under the same conditions. The bacterial solution was observed to see if it became turbid, or the absorbance value at 600 nm was measured by an enzyme-linked immunosorbent assay (ELISA) reader to help determine whether the bacterial solution became turbid at a certain concentration. If the bacterial solution at a certain concentration became turbid, it indicates that the bacteria can tolerate the environment of that concentration of heavy metals and survive.

[0030] As an example, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium, and then single colonies were picked and cultured in MB liquid medium at 35°C, 200 rpm, and 35°C in a shaker. When the seed culture reached the logarithmic growth phase, 0.05% of pre-prepared Ni was added. 2+Bacterial cultures were incubated in MB liquid medium at concentrations of 0 mg / L, 100 mg / L, 200 mg / L, 300 mg / L, 400 mg / L, and 500 mg / L under the same shaking conditions for 10 days. Observation revealed that the bacterial culture in the 400 mg / L MB liquid medium became turbid, while the culture in the 500 mg / L MB liquid medium remained turbid. This indicates that the bacteria can survive in concentrations below 500 mg / L Ni... 2+ Survival in high-concentration environments.

[0031] As an example, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium, and then single colonies were picked and cultured in MB liquid medium at 35°C, 200 rpm, and 35°C in a shaker. When the seed culture reached the logarithmic growth phase, 0.05% of pre-prepared Cd was added. 2+ Bacterial cultures were incubated in MB liquid medium at concentrations of 0 mg / L, 20 mg / L, 40 mg / L, 60 mg / L, 80 mg / L, and 100 mg / L under the same shaking conditions for 10 days. Observation revealed that the bacterial culture in the 0 mg / L MB liquid medium became turbid, while the culture in the 20 mg / L MB liquid medium remained turbid. This indicates that the bacteria can survive at concentrations below 20 mg / L of Cd. 2+ Survival in high-concentration environments.

[0032] As an example, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium, and then single colonies were picked and cultured in MB liquid medium at 35°C, 200 rpm, and 35°C in a shaker. When the seed culture reached the logarithmic growth phase, 0.05% of pre-prepared Cu was added. 2+ Bacterial cultures were incubated in MB liquid medium at concentrations of 0 mg / L, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, and 1000 mg / L under the same shaking conditions for 10 days. Observation revealed that the bacterial culture in 400 mg / L MB liquid medium became turbid, while the culture in 600 mg / L MB liquid medium remained turbid. This indicates that the bacteria can survive in concentrations below 600 mg / L Cu. 2+ Survival in high-concentration environments.

[0033] As an example, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium, and then single colonies were picked and cultured in MB liquid medium at 35°C, 200 rpm, and 35°C in a shaker. When the seed culture reached the logarithmic growth phase, 0.05% of pre-prepared Zn was added. 2+Bacterial cultures were incubated in MB liquid medium at concentrations of 0 mg / L, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, and 1000 mg / L under the same shaking conditions for 10 days. Observation revealed that the bacterial culture in 400 mg / L MB liquid medium became turbid, while the culture in 600 mg / L MB liquid medium remained turbid. This indicates that the bacteria can survive in concentrations of Zn below 600 mg / L. 2+ Survival in high-concentration environments.

[0034] In some embodiments, an application of bacteria capable of enriching heavy metals as described in this invention is also provided, wherein the bacteria are used to enrich cadmium, nickel, copper, and zinc.

[0035] In some embodiments, an application of bacteria capable of enriching heavy metals as described in this invention is also provided, wherein the bacteria are immobilized to form a bacterial agent for enriching cadmium, nickel, copper, and zinc.

[0036] The present invention will be further explained and illustrated below through specific embodiments:

[0037] Example 1

[0038] Immobilized Sinirhodobacter sp. 1C5-22 to prepare microbial inoculants

[0039] The target strain, *Sinirhodobacter* sp. 1C5-22, was immobilized. First, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium and fermented to obtain 400 mL of bacterial suspension. The suspension was then centrifuged at 8000 rpm for 10 min to collect the cells, which were washed twice with physiological saline to remove residual culture medium. Finally, the suspension was concentrated to approximately 30 mL. Materials required for immobilization included: ① 100 mL of sterilized PVA-SA (14% PVA and 1% SA) mixture, cooled to approximately 50°C; ② 500 mL of sterilized saturated boric acid and 5% CaCl2 solution, stored at 4°C. Then, 30 ml of bacterial suspension was added to 100 ml of a PVA (polyvinyl alcohol)-SA (sodium alginate) mixture (referring to an encapsulating agent for immobilizing microorganisms formed by the combination of polyvinyl alcohol and sodium alginate), and mixed thoroughly. Simultaneously, 500 ml of saturated boric acid and 5% CaCl2 solution were connected to the two ends of an automatic titration device (peristaltic pump and magnetic stirrer), respectively. The dropping rate was controlled at 0.1-0.3 ml / min and the stirring speed at 300-400 rpm, slowly adding the solution to the saturated boric acid and 5% CaCl2 solution. After titrating for 10-12 hours, small, smooth, uniform, and elastic spherical particles were obtained, such as… Figure 2As shown. The obtained microspheres were placed on ice for about 4 hours for cross-linking, then filtered to remove surface moisture, resulting in dried microsphere particles, which were collected and stored in a 4°C refrigerator.

[0040] Example 2

[0041] Sinirhodobacter sp.1C5-22 versus Cd 2+ Ni 2+ Cu 2+ and Zn 2+ Enrichment capacity test

[0042] First, *Sinirhodobacter* sp. 1C5-22 was activated on R2A solid medium. Then, single colonies were picked and cultured in SG liquid medium at 35°C and 200 rpm in a shaker. When the seed culture reached the logarithmic growth phase, it was transferred at a 5% inoculum to 400 mL of fresh SG liquid medium and cultured under the same conditions for approximately 36–48 h. The bacterial culture was then collected by centrifugation at 8000 rpm for 10 min and washed twice with high-purity water to remove residual culture medium. The bacterial cells were then added to pre-prepared fresh solutions containing heavy metal ions (25 mL each). 2+ Ni 2+ Cu 2+ and Zn 2+ The concentrations were 10 mg / L and 50 mg / L. The cells were incubated in a shaker at 200 rpm and 35°C for 2 hours. The supernatant was then collected by centrifugation, and the concentration of metal ions in the supernatant was determined using inductively coupled plasma optical emission spectrometry (ICP-OES, OPTIMA 7000, PerkinElmer). A blank solution without bacterial cells was used as a control. Each experiment was performed in triplicate. The results are shown below. Figure 3 and Figure 4 As shown.

[0043] The removal rate (R) and bioaccumulation rate (Q) of metal ions are calculated by the following formula.

[0044] R = (1-C) t / C0)×100%

[0045] Q = (C0 - C) t )×V / M

[0046] In the formula, R represents the removal rate (%) of metal ions by Sinirhodobacter sp.1C5-22, Q represents the bioaccumulation of metal ions by Sinirhodobacter sp.1C5-22 (mg / g), and C represents the bioaccumulation of metal ions by Sinirhodobacter sp.1C5-22. tC0 represents the final concentration (mg / L) of the solution after enrichment of metal ions by *Sinirhodobacter sp.1C5-22*, C0 represents the concentration (mg / L) of the solution before enrichment of metal ions by *Sinirhodobacter sp.1C5-22*, V represents the volume of the solution (L), and M represents the dry cell mass (g) of *Sinirhodobacter sp.1C5-22*. The final results are expressed as mean ± standard deviation.

[0047] Example 3

[0048] The encapsulation agent PVA-SA, composed of polyvinyl alcohol and sodium alginate, for immobilizing microorganisms, was added to a pre-prepared fresh solution containing heavy metal ions. The solution volume was 25 mL. 2+ Ni 2+ Cu 2+ and Zn 2+ The concentrations were 10 mg / L and 50 mg / L. The cells were incubated in a shaker at 200 rpm and 35°C for 2 hours. The supernatant was then collected by centrifugation, and the concentration of metal ions in the supernatant was determined using inductively coupled plasma optical emission spectrometry (ICP-OES, OPTIMA 7000, Perkin Elmer). A blank solution without bacterial cells was used as a control. Each experiment was performed in triplicate. The results are shown below. Figure 3 and Figure 4 As shown.

[0049] Example 4

[0050] The immobilized Sinirhodobacter sp. 1C5-22 bacterial agent prepared in Example 1 was added to a pre-prepared fresh solution containing heavy metal ions. The solution system consisted of 25 mL of Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The concentrations were 10 mg / L and 50 mg / L. The cells were incubated in a shaker at 200 rpm and 35°C for 2 hours. The supernatant was then collected by centrifugation, and the concentration of metal ions in the supernatant was determined using inductively coupled plasma optical emission spectrometry (ICP-OES, OPTIMA 7000, Perkin Elmer). A blank solution without bacterial cells was used as a control. Each experiment was performed in triplicate. The results are shown below. Figure 3 and Figure 4 As shown.

[0051] Example 5

[0052] Immobilization of Sinirhodobacter sp.1C5-22 against Cd 2+ Ni 2+ Cu2+ and Zn 2+ Enrichment capacity test

[0053] Using the immobilization method described in Example 1, a blank immobilized carrier PVA-SA was obtained without the addition of bacterial cells. 3-5 g of both the immobilized carrier and the immobilized bacterial cells from Example 1 were weighed and added to a pre-prepared fresh solution containing heavy metal ions. The solution volume was 25 mL. 2+ Ni 2+ Cu 2+ and Zn 2+ All concentrations were 10 mg / L. The cells were incubated in a shaker at 200 rpm and 35°C for 2 hours. The supernatant was then collected by centrifugation, and the concentration of metal ions in the supernatant was determined using inductively coupled plasma optical emission spectrometry (ICP-OES, OPTIMA 7000, Perkin Elmer). A blank solution without bacterial cells was used as a control. Each experiment was performed in triplicate. The results are shown below. Figure 5 As shown.

[0054] from Figure 3 - Figure 5 The results show that under the condition of a metal ion concentration of 10 mg / L, in a Cd atmosphere containing 10 mg / L... 2+ Ni 2+ Cu 2+ and Zn 2+ In solution, the removal rates of metal ions by the bacterium *Sinirhodobacter* sp. 1C5-22 were 67.91%, 70.09%, 75.17%, and 40.14%, respectively, with enrichment amounts of 5.79 mg / g, 5.90 mg / g, 7.69 mg / g, and 3.59 mg / g, respectively; in a solution containing 50 mg / L Cd... 2+ Ni 2+ Cu 2+ and Zn 2+ In the solution, the removal rates of metal ions were 19.27%, 23.87%, 43.32%, and 33.99%, respectively.

[0055] After immobilization, the bacteria Sinirhodobacter sp. 1C5-22 exhibited activity against the heavy metal Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ It exhibits higher removal capacity than unimmobilized strains in Cd 10 mg / L. 2+ Ni 2+ Cu 2+ and Zn 2+In the solution, the removal rates of metal ions were 78.59%, 93.20%, 90.89%, and 58.46%, respectively, and the enrichment amounts were 31.85 mg / g, 37.31 mg / g, 44.23 mg / g, and 24.83 mg / g, respectively; in a solution containing 50 mg / L Cd 2+ Ni 2+ Cu 2+ and Zn 2+ In the solution, the removal rates of metal ions were 30.77%, 40.22%, 65.29%, and 46.96%, respectively.

[0056] In summary, the bacterium *Sinirhodobacter* sp. 1C5-22 provided by this invention can effectively enrich Cd in solution. 2+ Ni 2+ Cu 2+ and Zn 2+ At 10 mg / L Cd 2+ Ni 2+ Cu 2+ The removal rates in the solutions were all above 50%, suggesting that *Sinirhodobacter* sp. 1C5-22 has potential remediation effects in environments contaminated with cadmium, nickel, and copper. The microbial agent prepared by immobilizing *Sinirhodobacter* sp. 1C5-22 as described in this invention exhibits better metal ion removal efficiency compared to unimmobilized strains, particularly in Ni... 2+ Cu 2+ The removal efficiency in solution reaches over 90%, and it is effective even at 10 mg / L Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The enrichment level of the bacteria in the solution was significantly higher than that of the unimmobilized strain, suggesting that the immobilized microbial agent has a better enrichment effect in actual heavy metal-contaminated wastewater compared to a single strain; the bacteria Sinirhodobacter sp.1C5-22 was enriched in 50 mg / L Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The removal rate in the solution was also above 30%; this study investigated the resistance to the heavy metal Cd. 2+ Ni 2+ Cu 2+ and Zn 2+ The bacteria Sinirhodobacters p. 1C5-22 that grows in Cd solution 2+ Ni 2+ Cu 2+ and Zn2+ The enrichment capacity of Sinirhodobacter sp.1C5-22 lays the foundation for research on the remediation of cadmium, nickel, copper and zinc polluted environments, enriches the microbial library for the remediation of heavy metal pollution by microorganisms, and provides technical support for the ultimate realization of the remediation of heavy metal pollution in water and soil by microorganisms.

[0057] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A bacterium capable of accumulating heavy metals, characterized in that, The bacteria belong to the genus *Sinorhodobacter*, and are named... Sinirhodobacter sp . 1C5-22, this strain was deposited at the China General Microbiological Culture Collection Center on September 26, 2022, with the accession number CGMCC No. 25796.

2. An application of bacteria capable of accumulating heavy metals as described in claim 1, characterized in that, The bacteria were used to enrich cadmium, nickel, copper, and zinc.

3. An application of bacteria capable of accumulating heavy metals as described in claim 1, characterized in that, The bacteria are then immobilized to form a microbial agent used for the enrichment of cadmium, nickel, copper, and zinc.

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