Application of antibacterial peptide AG-AFP
By using the antimicrobial peptide AG-AFP derived from Aspergillus megaterium, the problem of chemical control of sugarcane smut has been solved, achieving effective inhibition of sugarcane smut fungus and providing a new direction for sugarcane breeding, as well as an environmentally friendly control solution.
Patent Information
- Application Number
- CN202510762988.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-09
- Publication Date
- 2025-10-31
AI Technical Summary
In the existing technology, traditional chemical control methods for sugarcane smut are prone to leading to drug resistance of pathogens and environmental pollution. Traditional hybridization breeding is difficult to achieve a perfect combination of disease resistance traits and agronomic traits, and there are no reports on the effect of antimicrobial peptides in inhibiting sugarcane smut.
An antimicrobial peptide AG-AFP derived from Aspergillus megaterium, with the amino acid sequence shown in SEQ ID NO: 1, is provided. It can inhibit the growth of Ustilago canis and can be used in the preparation of biological agents and sugarcane transgenic breeding. The amino acid sequence is shown in SEQ ID NO: 1.
It effectively controls sugarcane smut, inhibits the growth of haploid yeast-type spores and dikaryotic mycelia of sugarcane smut fungus, provides an environmentally friendly control solution, and offers new directions for disease-resistant varieties in sugarcane breeding.
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Figure CN120865366A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of microbial technology, specifically to the application of an antimicrobial peptide AG-AFP. Background Technology
[0002] Sugarcane smut is a highly destructive fungal disease affecting sugarcane production. In severely affected areas (such as major sugarcane-producing countries like Brazil, India, China, and Thailand), losses can reach 20%-50% of sugarcane yield. Sugarcane smut is caused by *Ustilago maydis* (a fungus that causes sugarcane smut). Sporisorium scitanminea Caused by infection. Plants infected with smut exhibit stunted growth and development, with black spikes resembling whips emerging from the top of the stem, leading to a significant decrease in sugarcane yield and quality, causing substantial economic losses to the sugarcane industry. Traditional chemical control methods commonly use agents such as triadimefon and mancozeb, controlling the occurrence and spread of the disease through seedling disinfection and spraying. However, long-term use can easily lead to drug resistance in pathogens, and pesticide residues cause environmental pollution, posing risks to the ecological environment and human health. In the research and practice of sugarcane resistance to smut, traditional hybridization breeding has always been an important method for cultivating disease-resistant sugarcane varieties. However, because many sugarcane cultivars are alloaneuploid, the F1 offspring segregate, making it difficult to perfectly combine disease resistance traits with other major agronomic traits. Extensive hybridization and screening work is required to cultivate target varieties, which undoubtedly increases the difficulty of breeding.
[0003] Antimicrobial peptides, as novel biocontrol agents, exhibit multi-target mechanisms of action: on one hand, they can adsorb onto the cell membrane surface of pathogens through electrostatic interactions, forming pores or ion channels, leading to leakage of intracellular substances, disrupting cell membrane integrity, and causing pathogen death; on the other hand, some antimicrobial peptides can inhibit pathogen respiration, protein synthesis, cell wall synthesis, and other metabolic processes, interfering with normal cellular physiological functions to inhibit their growth; furthermore, antimicrobial peptides can act as signaling molecules to activate the plant's own immune system, inducing defensive responses such as activating the expression of relevant defense genes, promoting phytoalexin synthesis, and enhancing cell wall lignification, thereby improving the plant's resistance to pathogens. Due to these characteristics, antimicrobial peptides have advantages over chemical pesticides, including environmental friendliness, low toxicity to non-target organisms, and a lower likelihood of pathogen resistance, aligning with the concept of green agriculture. However, no antimicrobial peptides have been reported for inhibiting sugarcane smut. Summary of the Invention
[0004] The purpose of this invention is to overcome the problems existing in the prior art and provide an application of the antimicrobial peptide AG-AFP, which is a gene-encoded antimicrobial peptide AG-AFP that can inhibit the growth of sugarcane smut fungus.
[0005] To achieve the above objectives, the present invention provides an application of the antimicrobial peptide AG-AFP in inhibiting sugarcane smut, wherein the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0006] Preferably, the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium (…). Aspergillus giganteus ).
[0007] Preferably, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0008] Preferably, the minimum inhibitory concentration of the antimicrobial peptide AG-AFP for inhibiting the growth of sugarcane smut is 23.5 μg / mL.
[0009] A second aspect of the present invention provides the application of the antimicrobial peptide AG-AFP in the control of sugarcane smut, wherein the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0010] Preferably, the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium.
[0011] Preferably, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0012] The third aspect of the present invention provides the application of the antimicrobial peptide AG-AFP in the preparation of a biological agent for the prevention and control of sugarcane smut, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0013] The fourth aspect of this invention provides the application of the antimicrobial peptide AG-AFP in the construction of a prokaryotic expression vector, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0014] The fifth aspect of the present invention provides the application of the antimicrobial peptide AG-AFP in the preparation of transgenic sugarcane resistant to smut, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0015] This invention provides an antimicrobial peptide AG-AFP that can inhibit sugarcane smut fungus. AG-AFP inhibits the growth of haploid yeast-type spores and dikaryotic hyphae of sugarcane smut pathogen (Sugarcane smut fungus), thus effectively controlling sugarcane smut. Furthermore, AG-AFP is genetically encoded and can be used in subsequent transgenic sugarcane breeding to prepare smut-resistant varieties, providing a new direction for the control of sugarcane smut. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the prokaryotic expression vector of the antimicrobial peptide AG-AFP in Example 1 of the present invention; Figure 2 yes Figure 1 A partial structural diagram of the prokaryotic expression vector for the antimicrobial peptide AG-AFP; Figure 3 This is a graph showing the results of Tricine-SDS-PAGE electrophoresis and Western Blot analysis of the antimicrobial peptide AG-AFP in Example 1 of this invention. Figure 4 This is a graph showing the test results of the minimum inhibitory concentration of the antimicrobial peptide AG-AFP against *Ustilago maydis* in the test examples of this invention. Figure 5 This is a diagram showing the inhibition zone of the antimicrobial peptide AG-AFP against haploid spores of *Ustilago maydis* in the test examples of this invention. Figure 6 This is a diagram showing the inhibition zone of the antimicrobial peptide AG-AFP on the hyphae of *Ustilago maydis* after the amphoteric spores of *Ustilago maydis* have combined and grown in the test examples of this invention. Figure 7 This is a diagram showing the experimental results of liquid culture inhibition of sugarcane smut fungus by the antimicrobial peptide AG-AFP in the test examples of this invention. Detailed Implementation
[0017] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.
[0018] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0019] This invention provides the application of the antimicrobial peptide AG-AFP in inhibiting sugarcane smut, wherein the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0020] The sequence of SEQ ID NO: 1 is shown below: MQEMRARVLATYNGKCYKKDNICKYKAQSGKTAICKCYVKKCPRDGAKCEFDSYKGKCYC.
[0021] Furthermore, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0022] The sequence of SEQ ID NO:2 is shown below: ATGCAAGAGATGAGAGCGGGTTTTGGCCACATACAATGGCAAATGCTACAAGAAGGATAATATCTGCAAGTACAAGGCACAGAGCGGCAAGACTGCCATTTGCAAGTGCTATGTCAAAAAGTGCCCCCGCGACGGCGCGAAATGCGAGTTTGACAGCTACAAGGGGAAGTGCTACTGCAAGCTTGCGGCCGCACTCGAGCACCACCACCACCACCACTGA.
[0023] The antimicrobial peptide AG-AFP described in this invention is derived from Aspergillus megaterium (… Aspergillus giganteus ).
[0024] The antimicrobial peptide AG-AFP of the present invention consists of 60 amino acids (sequence as shown in SEQ ID NO: 1). The first 9 amino acid residues at the N-terminus form a secretion signal peptide, which is cleaved before or during extracellular secretion. The mature antifungal peptide has 51 amino acids and exerts its function after extracellular secretion. The 12 lysine residues in AG-AFP give this antimicrobial peptide a positive charge. The cation sites (K9, K10, K3) and hydrophobic domains (Y29, V30, Y45, V50) work together to give AG-AFP an amphiphilic character. The mature AG-AFP structure is characterized by a β-barrel topological conformation composed of five antiparallel β chains, which is stabilized by four disulfide bonds. Therefore, this antimicrobial peptide exhibits significant heat resistance and resistance to protease degradation. Derived from *Aspergillus megaterium*, this fungal antimicrobial peptide exhibits significantly better structural stability than plant-derived defensins. AG-AFP retains >80% activity after incubation at 80°C for 1 hour, while plant defensins (such as MtDef4 from alfalfa) show activity reduction to below 50% under the same conditions. In protease resistance experiments, the half-life of AG-AFP against trypsin is 3-5 times longer than that of plant defensins.
[0025] In this invention, the minimum inhibitory concentration of the antimicrobial peptide AG-AFP for inhibiting the growth of sugarcane smut is 23.5 μg / mL.
[0026] This invention also proposes the application of the antimicrobial peptide AG-AFP in the control of sugarcane smut, wherein the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1. Because the antimicrobial peptide AG-AFP inhibits the growth of haploid yeast spores and dikaryotic hyphae of *Ustilago maydis*, it can effectively control sugarcane smut.
[0027] Furthermore, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0028] Furthermore, the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium.
[0029] This invention also provides the application of the antimicrobial peptide AG-AFP in the preparation of a biological agent for controlling sugarcane smut, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1. Further, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0030] This invention does not limit the specific components of the biological agent, as long as it contains the antimicrobial peptide AG-AFP as described above. In some embodiments, the biological agent may contain excipients (e.g., starch, cellulose, gelatin, sucrose, etc.) and / or active ingredients capable of inhibiting sugarcane smut (e.g., triadimefon, mancozeb, etc.).
[0031] This invention does not limit the specific dosage form of the biological agent, and can be a dosage form commonly used in the field, such as at least one of the following: powder, wettable powder, oil, granules, aqueous solution and emulsifiable concentrate.
[0032] This invention also proposes the application of the antimicrobial peptide AG-AFP in the construction of a prokaryotic expression vector, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1. Further, the nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 2.
[0033] This invention also proposes the application of the antimicrobial peptide AG-AFP in the preparation of transgenic sugarcane resistant to smut, wherein the antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.
[0034] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto. Unless otherwise specified, the experimental methods in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available products.
[0035] The raw materials involved in the following embodiments and test examples include: Escherichia coli DH5α and E. coli BL21(DE3) was purchased from Novizan Biopharmaceutical Ltd.; pET21b plasmid is the property of our laboratory.
[0036] One-step cloning recombinase kit (Catalog No.: C112-02), protein extraction agarose gel beads: Ni-NTAAgarose (Catalog No.: F041-25mL), were purchased from Beijing Qidi Litai Technology Co., Ltd.; protein extraction reagents and SDS electrophoresis reagents: protease inhibitor Cocktail (Catalog No.: C0101), DTT (Catalog No.: 0281), 6 x SDS Loading Buffer (Catalog No.: G2525), pre-stained protein marker 10-180KD (Catalog No.: P1018), were purchased from Lamborghini Biotechnology Co., Ltd.; 10% One-Step PAGE Gel Fast Preparation Kit (Catalog No.: E301-01), 0.2 μM PVDF membrane (Catalog No.: E801 / 802-01 / 02), ECL developing solution (Catalog No.: E411-04 / 05); reagents used for immunoblotting: His-TagMouse Mixture Monoclonal. Antibody (catalog number: BE2072-10) and 10 kDa ultrafiltration tubes (catalog number: UFC901096) were purchased from Merck Millipore. Carbenicillin disodium (CAS: 4800-94-6) and DNA restriction endonucleases (BamHI, EcoRI, ApaI, HindIII, SphI, XbaI) were purchased from Lamborghini Biotechnology Co., Ltd.
[0037] The culture media involved in the following examples and test cases include: YEPSA plates: 10 g / L yeast extract, 20 g / L peptone and 20 g / L sucrose, plus 15 g / L agar powder; YEPS medium: yeast extract 10 g / L, peptone 20 g / L and sucrose 20 g / L.
[0038] Example 1 This embodiment illustrates the acquisition of the antimicrobial peptide AG-AFP described in this invention.
[0039] (1) Construction of prokaryotic expression vector for antimicrobial peptide AG-AFP An antimicrobial peptide AG-AFP synthesized by Aspergillus megaterium was screened (sequence shown in SEQ ID NO: 1).
[0040] Based on the nucleotide sequence obtained from the NCBI database (X53432.1) (sequence shown in SEQ ID NO: 2), the target gene fragment was synthesized and ligated between Xba I and Hind III at the multiple cloning site of the pET21b vector, and a His tag was fused to the C-terminus of the polypeptide. The prokaryotic expression vector for this antimicrobial peptide is as follows: Figure 1-2 As shown. The plasmid pET21b-AG-AFP-His was transformed into BL21 competent cells, plated on ampicillin-resistant plates, and incubated overnight at 37°C. Single colonies were picked for colony PCR and sequenced for verification.
[0041] (2) Expression and detection of antimicrobial peptide AG-AFP The positive strain obtained in step (1) was placed in LB liquid medium and cultured at 37°C and 220 rpm until OD. 600 The pH was set to 0.6-0.8. 0.1 M IPTG (isopropyl-β-D-thiogalactoside) was added, and the mixture was incubated overnight at 150 rpm at 15°C. The strain was collected by centrifugation and subjected to high-pressure disruption. Purification was performed using a Ni affinity column, followed by gradient elution with 0.01 M PBS (8 g / L NaCl, 0.2 g / L KCl, 1.44 g / L Na₂HPO₄, 0.24 g / L KH₂PO₄, pH 7.5) containing 20 mM and 40 mM imidazole, and then with PBS solutions containing 200 mM, 400 mM, and 600 mM imidazole (pH 7.5). The eluted antimicrobial peptide AG-AFP was concentrated using a 10 kDa ultrafiltration tube to obtain the concentrated antimicrobial peptide AG-AFP.
[0042] Take 30 μL of the concentrated antimicrobial peptide AG-AFP sample, mix it with 5× protein loading buffer, boil for 10 min, perform Tricine-SDS-PAGE electrophoresis and Coomassie Brilliant Blue staining, and detect it using His antibody via Western blotting. The detection results are as follows: Figure 3 As shown in the figure (M represents the protein marker 11 kDa-180 kDa), the results indicate that the antimicrobial peptide was successfully expressed, with the target band at 8.4 kDa.
[0043] Test case This test example illustrates the inhibitory effect of the antimicrobial peptide AG-AFP described in this invention on sugarcane smut.
[0044] 1. Minimum inhibitory concentration of antimicrobial peptide AG-AFP against sugarcane smut.
[0045] The minimum inhibitory concentration was determined using the two-fold dilution method, taking 1×10⁻⁶. 6JG35 and JG36 at CFU / mL were used as seed cultures. 100 μL of culture medium containing different concentrations of AG-AFP was added to each well of a 96-well plate, followed by 100 μL of the seed culture. The plates were incubated at 28℃ with shaking at 220 rpm for 24 h. OD was measured using a microplate reader. 600 The antibacterial effect was observed, and the test results are shown in Table 1 below. Figure 4 ( Figure 4 In the figure, A represents the result of JG35 and B represents the result of JG36.
[0046] Table 1
[0047] Table 1 and Figure 4 The experimental results show that when the concentration of AG-AFP reaches 23.5 μg / mL, it can achieve a significant antibacterial effect. 2. The antibacterial activity of haploid spores of Ustilago may be verified by an inhibition zone experiment.
[0048] The concentrated antimicrobial peptide AG-AFP obtained in Example 1 was filtered and sterilized using a 0.22 μm disposable syringe filter. The antimicrobial function of the filtered antimicrobial peptide AG-AFP was tested to verify its antimicrobial activity against haploid yeast spores of Ustilago canescens.
[0049] Haploid spores JG35 and JG36 were cultured overnight to obtain OD. 600 JG35 bacterial culture with an OD of 1.3 600 The concentration of JG36 bacterial suspension was 1.3. 600 μL of haploid spores from JG35 and JG36 were respectively spread onto YEPSA plates (8.5 cm in diameter). After drying, sterilized Oxford cups were placed on the culture medium, and 50 μL, 100 μL, and 200 μL (concentration 300 μg / mL) of filtered antimicrobial peptide AG-AFP were added sequentially to the Oxford cups. The experiment was conducted in triplicate, and the average diameter of the inhibition zone was taken. The plates were incubated at 28℃, and the presence or absence of inhibition zones was observed. After 12 h, the test results were as follows: Figure 5 As shown.
[0050] Figure 5 The results showed that a clear inhibition zone appeared at the Oxford cup position after the addition of the antifungal peptide AG-AFP. Measurements showed that in the JG35 experimental group, the diameters of the inhibition zones after adding 50 μL, 100 μL, and 200 μL of the antifungal peptide were 1.2 cm, 2 cm, and 2.5 cm, respectively; while in the JG36 experimental group, the diameters of the inhibition zones after adding 50 μL, 100 μL, and 200 μL of the antifungal peptide were 1.2 cm, 2.1 cm, and 2.9 cm, respectively. This indicates that the antifungal peptide can inhibit the growth of haploid yeast-type spores of *Ustilago maydis*.
[0051] 3. The antibacterial activity of the dikaryotic mycelium of *Ustilago maydis* was verified by an inhibition zone experiment.
[0052] Since *Ustilago maydis* can only form dikaryotic hyphae through the fusion of hermaphroditic haploid spores, therefore, OD... 600 300 μL each of wild-type haploid spores JG35 and JG36 of *Ustilago maydis* (both 1.3 μg / mL) were mixed and spread onto YEPSA plates. After drying, Oxford cups were placed on the culture medium, and 200 μL (300 μg / mL) of filtered antimicrobial peptide AG-AFP was added to the Oxford cups. The plates were incubated at 28°C for 4 days. The test results are as follows. Figure 6 As shown.
[0053] Figure 6 The results showed that the plates exhibited a distinct inhibition zone, which was measured to be 2.3 cm in diameter.
[0054] 4. Liquid culture was used to verify the inhibitory activity of the antimicrobial peptide on sugarcane smut.
[0055] Single colonies of yeast spore JG35 were picked and inoculated into 20 mL of liquid YEPS medium and cultured overnight at 28°C and 220 rpm to obtain a concentration of 1×10⁻⁶. 6 JG35 seed culture at CFU / mL; yeast spores JG36 were cultured using the same method to obtain a concentration of 1×10⁻⁶. 6 JG36 seed culture at CFU / mL.
[0056] 500 μL of antimicrobial peptide AG-AFP solution (concentration 300 μg / mL) was added to 2.5 mL of liquid YEPS medium. 15 μL of the above JG35 and JG36 seed cultures were then inoculated separately and incubated at 28℃ and 220 rpm for 48 h. The experiment was performed in triplicate, and the results are shown below. Figure 7 As shown.
[0057] Figure 7 The experimental results showed that the growth of JG35 and JG36 was significantly inhibited after the addition of antimicrobial peptide AG-AFP to the culture medium (final concentration of 50 μg / mL), indicating that the antimicrobial peptide AG-AFP described in this invention has strong antimicrobial activity against sugarcane smut. After 48 hours, the OD of the JG35 experimental group with added antimicrobial peptide AG-AFP was measured. 600 The OD of the JG35 control group was 0.0738. 600 The OD of the JG36 experimental group with added antimicrobial peptide AG-AFP was 1.5. 600 The OD of the JG36 control group was 0.0723. 600 It is 1.6.
[0058] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.
Claims
1. Application of antimicrobial peptide AG-AFP in inhibiting sugarcane smut, among which, The amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
1.
2. The application according to claim 1, characterized in that, The antimicrobial peptide AG-AFP is derived from Aspergillus megaterium (… Aspergillus giganteus ).
3. The application according to claim 1 or 2, characterized in that, The nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
2.
4. The application according to any one of claims 1-3, characterized in that, The minimum inhibitory concentration of the antimicrobial peptide AG-AFP for inhibiting the growth of sugarcane smut is 23.5 μg / mL.
5. Application of antimicrobial peptide AG-AFP in the control of sugarcane smut, among which, The amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
1.
6. The application according to claim 5, characterized in that, The antimicrobial peptide AG-AFP is derived from Aspergillus megaterium.
7. The application according to claim 5 or 6, characterized in that, The nucleotide sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
2.
8. Application of the antimicrobial peptide AG-AFP in the preparation of biological agents for the control of sugarcane smut, among which, The antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
1.
9. Application of the antimicrobial peptide AG-AFP in the construction of prokaryotic expression vectors, among which, The antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO:
1.
10. Application of the antimicrobial peptide AG-AFP in the preparation of transgenic sugarcane resistant to smut, among which, The antimicrobial peptide AG-AFP is derived from Aspergillus megaterium, and the amino acid sequence of the antimicrobial peptide AG-AFP is shown in SEQ ID NO: 1.