Marine bacteria capable of preying on human pathogenic bacteria and application thereof

Abstract

The application discloses a marine bacterium capable of preying on human pathogenic bacteria and application thereof, and belongs to the technical field of microorganisms. Hahella chejuensis The marine bacterium capable of preying on human pathogenic bacteria is Hoshiiella jejuensis (GXIMD14048) with a preservation number of CGMCC No. 37275. The bacterium is obtained by being separated from mangrove soil, has preying activity on Staphylococcus aureus, Pseudomonas aeruginosa, Micrococcus luteus, Escherichia coli and Acinetobacter baumannii, and the preying effect on Acinetobacter baumannii is particularly remarkable. The application further provides a systematic screening method of the bacterium, which comprises sample treatment, separation and purification, initial screening and verification steps. The bacterium can be used for preparing antibacterial preparations and has a good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of microbial technology, and specifically relates to a marine bacterium that can prey on human pathogens and its applications. Background Technology

[0002] Currently, bacterial resistance has become a major challenge in global public health, especially with the emergence of multidrug-resistant and extensively drug-resistant bacteria, which increasingly limits the effectiveness of traditional antibiotic treatments. Therefore, developing novel antimicrobial strategies is particularly urgent. Predatory bacteria, which can lyse or kill other living bacteria and utilize their macromolecules as nutrients or raw materials for biosynthesis, are considered a potential alternative to antibiotics. Existing technologies include methods for screening and identifying predatory bacteria, such as assessing bacterial predatory activity through streak plating and droplet co-culture.

[0003] However, the existing technology still has the following shortcomings, for example: (1) Traditional methods mostly rely on a single culture medium and a long culture period (usually more than one month), and the initial screening method for predatory activity is not sensitive and is easy to miss; (2) Most known predatory bacteria have predatory activity against environmental strains or plant pathogens, and there are few research reports on human pathogens, making it difficult to deal with the multidrug-resistant bacteria commonly seen in clinical practice; (3) Existing methods are mostly limited to qualitative observation and lack quantitative or semi-quantitative predatory effect evaluation system, making it difficult to accurately compare the predatory ability of different strains; (4) There is a lack of systematic screening schemes for predatory bacteria from marine sources, especially insufficient research on the predatory activity of strains in special habitats such as mangroves.

[0004] Therefore, there is an urgent need to establish an efficient, systematic, and quantitatively assessable screening method for predatory bacteria, and to screen out strains with broad-spectrum predatory activity in order to address the increasingly serious problem of bacterial resistance. Summary of the Invention

[0005] In view of the above, the present invention provides a marine bacterium GXIMD14048 (classified name) capable of preying on human pathogens. Hahella chejuensis The study describes *Hypericum japonicum* (Jeju Island strain) and provides its screening methods and applications. Hahella chejuensis The GXIMD14048 strain exhibits significant predatory activity against a variety of human pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, Micrococcus luteus, Escherichia coli, and Acinetobacter baumannii, with the highest predatory efficiency against Acinetobacter baumannii, demonstrating broad prospects for antibacterial applications.

[0006] This invention provides a marine bacterium capable of preying on human pathogens, wherein the marine bacterium capable of preying on human pathogens is Jeju Island cholerae (Jeju Island cholerae). Hahella chejuensis GXIMD14048, its classification name is: Hahella chejuensis GXIMD14048, accession number CGMCC No. 37275; this Jeju Island Hodgkin's bacterium ( Hahella chejuensis GXIMD14048 is deposited at the China General Microbiological Culture Collection Center, located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, on January 4, 2026.

[0007] The present invention also provides an application of the marine bacteria as described above, wherein the marine bacteria are used to prey on Acinetobacter baumannii (… Acinetobacter baumannii ).

[0008] The present invention also provides an application of the marine bacteria as described above, wherein the marine bacteria are used to prey on Staphylococcus aureus (Staphylococcus aureus). Staphylococcus aureus ), Pseudomonas aeruginosa ( Pseudomonas aeruginosa Micrococcus luteus ( Micrococcus luteus ) and Escherichia coli ( Escherichia coli At least one pathogenic bacterium in the group consisting of 1, 2, 3, 4, 5, 6

[0009] The present invention also provides a method for screening marine bacteria as described above, comprising the following steps:

[0010] a. Sample preparation: processing and dilution of mangrove soil samples;

[0011] b. Separation and purification: Spread on a mixed medium of 1 / 10MA, 1 / 10R2A or 1 / 10MA and 1 / 10R2A in a 1:1 volume ratio, and incubate at 28°C for more than one month;

[0012] c. Initial screening for activity: Select single colonies for purification, extract DNA, and perform 16S rRNA sequencing for identification;

[0013] d. Verification: Its predatory activity against pathogenic bacteria was verified by the streak-over method and the droplet method.

[0014] To further clarify, the pathogenic bacteria include at least one of Staphylococcus aureus, Pseudomonas aeruginosa, Micrococcus luteus, Escherichia coli, and Acinetobacter baumannii.

[0015] The present invention has the following beneficial effects:

[0016] The Jeju Island strain of *Acinetobacter cholerae* GXIMD14048, screened by our research team, exhibited predatory activity against five common human pathogens, particularly showing significant predatory activity against multidrug-resistant *Acinetobacter baumannii*. Droplet co-culture experiments confirmed that this Jeju Island strain of *Acinetobacter cholerae*... Hahella chejuensisThe GXIMD14048 strain can completely cover Acinetobacter baumannii colonies in a relatively short period of 7 days; the screening method provided by this invention combines streak primary screening with droplet quantitative verification, improving the accuracy and repeatability of screening; this Jeju Island Hodgkin's bacterium ( Hahella chejuensis The GXIMD14048 strain exhibited antibacterial effects comparable to polymyxin B in liquid co-culture, and can be considered as a potential biological antibacterial agent or antibacterial adjuvant. Attached Figure Description

[0017] Figure 1 This is a colony morphology diagram of strain GXIMD14048.

[0018] Figure 2 This is a phylogenetic tree diagram of strain GXIMD14048.

[0019] Figure 3 This is a schematic diagram of the predatory activity results using the cross-line method; where... Figure 3 a represents the predation results of Jeju Island *Holothuria cholerae* GXIMD14048 on *Pseudomonas aeruginosa*. Figure 3 b represents the predation results on Acinetobacter baumannii. Figure 3 c represents the predation result on Escherichia coli. Figure 3 d represents the predation result on Staphylococcus aureus. Figure 3 e represents the predation result of Micrococcus luteus; Figure 3 f is a negative control; Figure 3 g is the control for inhibition.

[0020] Figure 4 This is a schematic diagram showing the results of droplet method for capturing pathogenic bacterial colonies; in which Figure 4 a represents the predation results of Jeju Island *Holothuria cholerae* GXIMD14048 on *Pseudomonas aeruginosa*. Figure 4 b represents the predation results on Acinetobacter baumannii. Figure 4 c represents the predation result on Escherichia coli. Figure 4 d represents the predation result on Staphylococcus aureus. Figure 4 e represents the predation result of Micrococcus luteus; Figure 4 f is a negative control without predation.

[0021] Figure 5 This is a schematic diagram of the time-dynamic predation process; in which Figure 5 ae represent the dynamic observation of the predation process of Jeju Island's *Hormones cholerae* GXIMD14048 on *Pseudomonas aeruginosa*, *Acinetobacter baumannii*, *Escherichia coli*, *Staphylococcus aureus*, and *Micrococcus luteus* over a 20-day period.

[0022] Figure 6 This is a schematic diagram illustrating the regrowth of pathogenic bacteria after predation. Figure 6Figure a shows the results of Jeju Island *Hordeella harzianum* GXIMD14048 preying on *Acinetobacter baumannii* for 16 days. Figure 6 b shows the streaking results of Jeju Island *Hordeella harzianum* GXIMD14048 after it preyed on *Acinetobacter baumannii* for 16 days. Figure 6 c is an enlarged image of the streaked growth of Jeju Island Hodgkin bacteria GXIMD14048 after 16 days of predation on Acinetobacter baumannii. Figure 6 d shows the results of Jeju Island *Hypertropha cholerae* GXIMD14048 preying on *Micrococcus luteus* for 16 days. Figure 6 e shows the streaking results of *Hypertropha cholerae* GXIMD14048 from Jeju Island after 16 days of predation on *Micrococcus luteus*. Figure 6 f is a magnified image showing the streaking growth of Jeju Island's *Hypertropha cholerae* GXIMD14048 after 16 days of predation on *Micrococcus luteus*. Figure 6 g shows the natural growth of Acinetobacter baumannii in 1 / 2 MA medium. Figure 6 h shows the natural growth of Micrococcus luteus on 1 / 2 MA medium.

[0023] Figure 7 This image shows a comparison of the antibacterial effects of Jeju Island's *Hormonella cholerae* GXIMD14048 and polymyxin B against *Acinetobacter baumannii*. Figure 7 Figure a shows a comparison of colony counts after co-culturing Jeju Island's *Hormonella cholerae* GXIMD14048 and *Acinetobacter baumannii* for 24 hours. Figure 7 Figure b shows a comparison of colony counts of Jeju Island Holothurst GXIMD14048 after treatment with 2 μg / ml polymyxin B. Figure 7 c is a comparison of colony counts of Acinetobacter baumannii alone under the same culture conditions.

[0024] The applicant has already screened out Jeju Island Hodgkin's bacillus ( Hahella chejuensis GXIMD14048 is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 37275; address: No. 3, No. 1 Beichen West Road, Chaoyang District, Beijing; deposit date: January 4, 2026. Detailed Implementation

[0025] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0026] Unless otherwise stated, each feature disclosed in this specification is merely one example of a series of equivalent or similar features.

[0027] Test culture medium

[0028] (1) MA / 10 (g / L): Peptone 0.5 g, yeast extract 0.1 g, ferric citrate 0.01 g, NaCl 1.945 g, MgCl2·6H2O 0.59 g, Na2SO4 0.324 g, CaCl2 0.18 g, KCl 0.055 g, NaHCO3 0.016 g, KBr 0.008 g, SrCl2·6H2O 0.0034 g, H3BO3 0.0022 g, Na2SiO3 0.0004 g, NaF 0.00024 g, NH4NO3 0.00016 g, Na2HPO4 0.0008 g, agar (solid only) 15 g (sterilized at 115℃ for 20 min).

[0029] (2) R2A / 10 (g / L): tryptone 0.05 g, yeast extract 0.05 g, casein hydrolysate 0.05 g, glucose 0.05 g, soluble starch 0.05 g, KH2PO4 0.03 g, K2HPO4 0.03 g, MgSO4·7H2O 0.0024 g, agar (solid only) 15 g.

[0030] (3) MA / 2 (g / L): peptone 2.5 g, yeast extract 0.5 g, ferric citrate 0.05 g, NaCl 9.725 g, MgCl2·6H2O 2.95 g, Na2SO4 1.62 g, CaCl2 0.9 g, KCl 0.275 g, NaHCO3 0.08 g, KBr 0.04 g, SrCl2·6H2O 0.017 g, H3BO3 0.011 g, Na2SiO3 0.002 g, NaF 0.0012 g, NH4NO3 0.0008 g, Na2HPO4 0.004 g, agar (solid only) 15 g (sterilized at 115℃ for 20 min).

[0031] (4) Taq PCR Mix premix (2×, containing blue dye), purchased from Sangon Biotech (Shanghai) Co., Ltd.; Chelex-100 resin, BIO-RAD, USA; PCR primers (27F, 1492R), synthesized by Sangon Biotech (Shanghai) Co., Ltd.

[0032] Example 1

[0033] This embodiment describes the isolation, screening, and identification of marine bacteria capable of preying on human pathogens.

[0034] 1. Culture of predatory bacteria in mangrove soil samples: Weigh 2.0 g of mangrove soil sample from Qinzhou and place it in an Erlenmeyer flask. Add 18.0 mL of sterile seawater and 2.0 g of sterile quartz sand. Place the flask on a shaker and shake at 180 r / min for 1 hour to obtain the original sample solution. Dilute the solution to 10% of its original concentration. -1 10 -2 10 -3 Multiply, take 10 -3 The concentrations were respectively spread into a mixed culture medium of 1 / 10MA, 1 / 10R2A, and 1 / 10MA and 1 / 10R2A in a 1:1 volume ratio, and incubated at 28℃ for 2-3 months.

[0035] 2. Isolation, purification, and identification of predatory bacteria: Single colonies were picked from the isolation medium and inoculated onto 1 / 2 MA medium using the three-zone streak method. Purification was continued until single colonies were obtained. Morphological characteristics (color, shape, size, and whether pigments were produced, etc.) and colony count were recorded. The purified bacteria were initially deduplicated based on morphological characteristics. Bacterial genomic DNA was extracted using the Chelex-100 method. PCR amplification was performed using universal primers 27F (5'-AGAGTTTGATCCTGGCTCAG-3') and 1492R (5'-GGTTACCTTGTTACGACTT-3'). PCR reaction system (25 μL): 12.5 μL 2×Taq PCR Mix premix, 1 μL primer 27F (10 μmol / L), 1 μL primer 1492R (10 μmol / L), 2 μL DNA template, and ddH2O to a final volume of 25 μL. Amplification conditions: 95℃ pre-denaturation for 5 min; 95℃ denaturation for 30 s, 55℃ annealing for 30 s, 72℃ extension for 90 s, for a total of 30 cycles; final extension at 72℃ for 10 min. Amplified products were detected by 1% agarose gel electrophoresis. Positive amplified products were sequenced by Sangon Biotech (Shanghai) Co., Ltd., Guangzhou Branch. The purified strain was stored in 25% (v / v) glycerol tubes at -80℃ for long-term preservation.

[0036] After 24 hours of incubation, circular, raised colonies were observed growing on 1 / 2 MA culture dishes. The colony edges were uneven and sunken into the culture medium, with irregularly raised surfaces. The bacteria were red and produced red pigment during liquid culture. The colony size was approximately 0.2 mm (e.g., ...). Figure 1 ).

[0037] Identified by 16S rRNA and Hahella chejuensis The similarity was 99.2%, and it belongs to the order Pseudomonas ( ). Pseudomonadales ), Herbadaceae ( Hahellaceae ), Harvestia spp. Hahella ) identification (such as Figure 2 This strain was classified and named Hahella chejuensis GXIMD14048, classified in Chinese as Jeju Island Hodgkin's bacterium.

[0038] The applicant has already screened out Jeju Island Hodgkin's bacillus ( Hahella chejuensis GXIMD14048 is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 37275; address: No. 3, No. 1 Beichen West Road, Chaoyang District, Beijing; deposit date: January 4, 2026.

[0039] Example 2:

[0040] This example demonstrates a preliminary screening study of the predatory activity of Jeju Island strain GXIMD14048 of *Holothuria cholerae* using the streak-strike method.

[0041] The Jeju Island strain of *Hodgkin's cholerae* GXIMD14048, isolated in Example 1, was subjected to a streak plating experiment. *Pseudomonas aeruginosa* was selected as a secondary strain. Pseudomonas aeruginosa Acinetobacter baumannii ( Acinetobacter baumannii ), Escherichia coli ( Escherichia coli Staphylococcus aureus ( Staphylococcus aureus Micrococcus luteus ( Micrococcus luteus Five prey bacteria and two control bacteria: ① one marine bacterium known to have no predatory activity (laboratory-preserved). Jeotgalibacillus alimentarius ① DSM 18867) as a negative control; ② A marine bacterium known to have antagonistic activity but no predatory activity (laboratory-preserved). Pseudoalteromonas piscicida ATCC 15057 was used as an antagonistic control, and the prey strain was streaked across the isolated bacteria on 1 / 2 MA solid medium. The prey strain was streaked first, followed by the test strain, with the crossover point located in the center of the plate. The plates were incubated at 28°C for 10 days, and the growth of pathogenic bacteria around the streaked bacteria was observed.

[0042] Results: After culturing for 3-5 days using the streak method, the Jeju Island strain of *Hormonella jejuae* GXIMD14048 was observed to exhibit predatory activity against five human pathogens: *Staphylococcus aureus*, *Pseudomonas aeruginosa*, *Micrococcus luteus*, *Escherichia coli*, and *Acinetobacter baumannii*. Figure 3 ae). By Figure 3 As can be seen from the results, the growth of pathogenic bacteria around the active strain is inhibited, or the active strain grows onto the pathogenic bacteria, limiting their growth (colony disappearance or the test strain grows along the pathogenic bacterial colony, causing it to lyse). In the antagonistic effect control group, a transparent inhibition zone (crystal fading but no predatory bacteria growth in the center) can be observed after the antagonistic strain and the pathogenic bacteria are crossed and streaked, and its phenotype is significantly different from its predatory activity. Figure 3 f, in the negative control group, strains without predatory activity Jeotgalibacillus alimentarius After H3L1-2 was cross-stretched with Pseudomonas aeruginosa, no colony fading or clear zone formation was observed within 10 days of incubation, and the pathogenic bacteria grew normally. This negative control result indicates that the antibacterial effect of GXIMD14048 has predation specificity. Furthermore, compared with the antagonistic effect control (…), Figure 3 The comparison with g) further confirms that the inhibitory effect of GXIMD14048 on pathogenic bacteria stems from predation behavior rather than simple antagonism.

[0043] Example 3:

[0044] This example demonstrates the use of the droplet method to verify the predatory ability of Jeju Island strain GXIMD14048 of *Hodgkin's cloacae* and to dynamically observe the predatory process over time.

[0045] Verification of the predatory ability of live strains:

[0046] Jeju Island strain of *Hodgkin's cholerae* GXIMD14048 was inoculated into 1 / 2 MA liquid medium, and the prey bacteria were inoculated into LB liquid medium. Both were incubated overnight at 28°C and 180 rpm in a constant-temperature shaker. The bacterial cells were collected by centrifugation, washed once with sterile physiological saline, resuspended, and the bacterial suspension concentration was adjusted to OD0.05. 600 =1.0 (corresponding to 1×10) 8 (CFU / mL).

[0047] This study prepared Pseudomonas aeruginosa (… Pseudomonas aeruginosa ) bacterial suspension, Acinetobacter baumannii ( Acinetobacter baumannii ) bacterial suspension, Escherichia coli ( Escherichia coli ) bacterial suspension, Staphylococcus aureus ( Staphylococcus aureus ) bacterial suspension and Micrococcus luteus ( Micrococcus luteus The bacterial suspension is the prey bacteria;

[0048] 5 μL of active bacterial suspension and 5 μL of prey bacterial suspension were respectively prepared as follows: Figure 4 The bacterial culture was spotted onto 1 / 2 MA solid medium as shown in ae. After the culture was dried, it was incubated at 28°C for 10 days, and the predation phenomenon was observed.

[0049] result:

[0050] 1. The predatory effect of the live bacterial strain was assessed by comparing the area of ​​pathogenic bacterial colony disappearance after the live strain invaded. Predatory activity on day 10 after droplet inoculation is shown below. Figure 4 As shown in ae, strain Jeju Island Hodgkin's strain GXIMD14048 exhibits the most pronounced predation on neighboring colonies, among which Acinetobacter baumannii ( Acinetobacter baumannii The largest area of ​​colony invasion (almost all of them disappeared) indicates that this group has the strongest predation activity.

[0051] 2. The predatory activity of strain Jeju Island Hodgkinella GXIMD14048 against neighboring pathogens was observed from day 1 to 28 after inoculation using the droplet method. The results are shown in […]. Figure 5 ae. "Predation" is defined as visible morphological damage to the prey fungal colony caused by the action of predatory bacteria, including but not limited to indented colony edges, transparent halos, or significant color lightening, and this change depends on direct contact between the predatory and prey fungi; "maximum predation" is defined as the predatory fungal moss completely covering the original prey fungal colony area. The predatory fungus grows completely in the original area of ​​the prey fungal colony, forming a continuous moss cover, and no live prey fungi can be detected in this area. Its effect on Acinetobacter baumannii (…) can be observed as early as day 2. Acinetobacter baumannii ) and Micrococcus luteus ( Micrococcus luteus It exhibited predatory behavior. On the 7th day, it showed predatory behavior towards Acinetobacter baumannii (…). Acinetobacter baumannii The predation rate of *Micrococcus luteus* reached its maximum, almost completely covering the entire colony. On day 12, its predation on *Micrococcus luteus* (…) reached its maximum. Micrococcus luteus The predation rate of *Acinetobacter baumannii* reaches its maximum around day 22; it reaches its maximum predation rate on all pathogens, covering the entire colony. The strain *Acinetobacter cholerae* GXIMD14048 exhibits maximum predation against *Acinetobacter baumannii* (…). Acinetobacter baumannii The highest predation efficiency was achieved by *Micrococcus luteus*, followed by *Micrococcus luteus*.

[0052] Example 4:

[0053] This example demonstrates the survival of pathogenic bacteria following predation by Jeju Island strain GXIMD14048 of *Holothuria foetida*.

[0054] Jeju Island's *Hordeum vulgare* GXIMD14048 and *Acinetobacter baumannii* ( Acinetobacter baumannii Micrococcus luteus ( Micrococcus luteus After culturing according to the method in Example 3 until day 16, the bacterial growth completely covered by the predatory bacteria was scraped off with a sterile inoculation loop and inoculated into fresh 1 / 2 MA solid medium using the three-zone streak method. The medium was then placed at 28°C and incubated for 2-3 days to observe the survival of the pathogenic bacteria.

[0055] See results Figure 6 a and Figure 6 d. After 16 days of culture using the droplet method, observation under an optical microscope showed that Jeju Island Hodgkin bacteria GXIMD14048 had completely covered and occupied the culture area. Acinetobacter baumannii and Micrococcus luteus in the predation area had basically disappeared, and no obvious colony structure was observed, while Jeju Island Hodgkin bacteria proliferated vigorously. Figure 6 g and Figure 6h represents the untreated positive control group. It was observed that both *Acinetobacter baumannii* and *Micrococcus luteus* grew well after 3 days of incubation at 28°C on 1 / 2 MA medium, forming abundant, continuous, dense bacterial moss or typical colonies, indicating that both pathogenic bacteria possess normal survival and proliferation capabilities even without predatory pressure. This contrasts sharply with… Figure 6 bc, showing Acinetobacter baumannii ( Acinetobacter baumannii Only 3 single colonies grew. Figure 6 ef. Micrococcus luteus ( Micrococcus luteus No bacterial colony growth was observed. (Summary) Figure 6 The results indicate that Jeju Island's *Hordeella harzianum* GXIMD14048 has a significant predatory effect on *Micrococcus luteus* and *Acinetobacter baumannii*.

[0056] Example 5:

[0057] This example evaluates the predation efficiency of Jeju Island strain *Hordeella harzianum* GXIMD14048 on *Acinetobacter baumannii*.

[0058] Specifically, the inhibitory effect was compared between liquid co-culture and the positive control drug polymyxin B:

[0059] Jeju Island Haemophilus cholerae GXIMD14048 was co-cultured with Acinetobacter baumannii for 24 hours, and compared with Acinetobacter baumannii with 2 μg / mL polymyxin B for 24 hours.

[0060] Experimental group: Jeju Island *Hormonella cholerae* GXIMD14048 + *Acinetobacter baumannii* co-cultured. Diluted with 1 / 2 MA liquid medium to a final concentration of 1×10⁻⁶ for each. 7 The co-culture system was prepared with CFU / mL and a total volume of 1 mL. It was then incubated in a constant-temperature shaker at 28℃ and 180 r / min.

[0061] Positive drug control group: Acinetobacter baumannii (initial concentration 1×10⁻⁶) 7 CFU / mL) + polymyxin B (final concentration 2 μg / mL, which is twice the minimum inhibitory concentration (MIC) of Acinetobacter baumannii determined in our laboratory), in the same culture medium and culture conditions.

[0062] Negative control group: Acinetobacter baumannii cultured alone (initial concentration 1×10⁻⁶) 7 (CFU / mL).

[0063] After culturing for 24 hours, each culture was serially diluted 10-fold. 100 μL of each diluted culture was spread onto 1 / 2 MA solid medium and incubated at 28°C for 24 hours. Colony forming units (CFU / mL) were then counted.

[0064] The results are shown in the table below:

[0065] Table 1. Comparison of the antibacterial effects of Jeju Island's *Clostridium chrysogenum* GXIMD14048 and polymyxin B against *Acinetobacter baumannii*.

[0066]

[0067] The viable bacterial counts in both the experimental group and the polymyxin B group (positive drug control group) decreased to approximately 10. 4 Both CFU / mL and CFU / mL exhibited considerable inhibitory activity against Acinetobacter baumannii. This indicates that Jeju Island's *Hordeella harzianum* GXIMD14048 possesses a significant predatory and inhibitory ability against *Acinetobacter baumannii*. (See results below.) Figure 7 .

[0068] In summary, through systematic screening, this invention successfully isolated a marine bacterium with broad-spectrum predatory activity from the soil of mangrove forests in Qinzhou. Hahella chejuensis GXIMD14048. This is Jeju Island's *Hodgkin's bacterium* (…). Hahella chejuensis The GXIMD14048 strain exhibits highly efficient predation capabilities against a variety of human pathogens (especially Acinetobacter baumannii), and its predation effect is comparable to that of traditional antibiotics, demonstrating promising prospects for development and application.

[0069] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A marine bacterium capable of preying on human pathogens, characterized in that, The marine bacteria that can prey on human pathogens is Jeju Island cholerae (Jeju Island cholerae). Hahella chejuensis) GXIMD14048, its classification name is: Hahella chejuensis GXIMD14048, accession number CGMCC No. 37275; this Jeju Island Hodgkin's bacterium ( Hahella chejuensis) GXIMD14048 is deposited at the China General Microbiological Culture Collection Center, located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, on January 4, 2026.

2. The Jeju Island Hodgkin's bacterium as described in claim 1 ( Hahella chejuensis) GXIMD14048 was used in the preparation of a product for preying on Acinetobacter baumannii ( Acinetobacter baumannii Application in biological antibacterial agents or antibacterial adjuvants.

3. The Jeju Island Hodgkin's bacterium as described in claim 1 ( Hahella chejuensis) GXIMD14048 was used in the preparation of a drug for predation of Staphylococcus aureus. Staphylococcus aureus ), Pseudomonas aeruginosa ( Pseudomonas aeruginosa Micrococcus luteus ( Micrococcus luteus ) and Escherichia coli ( Escherichia coli Application in biological antimicrobial agents or antimicrobial adjuvants of at least one pathogenic bacterium.

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