An antimicrobial peptide and its application

Abstract

The present invention relates to the field of molecular biology, and in particular to an antimicrobial peptide and an application thereof. The antimicrobial peptide is shown by the amino acid sequence in the sequence table SEQ ID No. 1. The antimicrobial peptide is used to prepare an inhibitor against bacterial infection. The antimicrobial peptide of the present invention has obvious antibacterial effects on different bacteria. At the same time, the antimicrobial peptide has strong stability to temperature and pH, and can be used to resist bacterial infection.

Description

Technical Field

[0001] The invention relates to the field of molecular biology, in particular to an antimicrobial peptide and application thereof. Background Art

[0002] Antimicrobial peptides are small molecule peptides widely found in nature. They have broad antibacterial properties, will not induce bacterial resistance, and have broad application prospects. In the past few decades, the extensive use of antibiotics has led to bacterial resistance and even the emergence of super bacteria, which poses a huge threat to the environment. The emergence of antimicrobial peptides provides a new perspective for solving the problem of antibiotics. They have a small molecular weight, a wide antibacterial spectrum, strong activity, good stability, no harmful residues when entering the body, and will not cause bacterial resistance. They have gradually become a substitute for traditional antibiotics. Antimicrobial peptides are generally composed of 10 to 60 amino acids. They are a class of small molecule peptides that are widely found in organisms in nature and are an important component of biological innate immunity. They are usually composed of cationic and hydrophobic amino acids, so they have cationic (positively charged) and amphiphilic (hydrophilic and hydrophobic) characteristics. Studies have reported that antimicrobial peptides have significant inhibitory effects on bacteria, fungi, viruses and parasites. Summary of the invention

[0003] The present invention aims to provide an antimicrobial peptide and application thereof.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is:

[0005] An antimicrobial peptide, the antimicrobial peptide is represented by the amino acid sequence in SEQ ID No. 1 in the sequence table.

[0006] An application of the antimicrobial peptide, wherein the antimicrobial peptide is used for preparing an inhibitor against bacterial infection.

[0007] The bacteria are one or more of Escherichia coli, Staphylococcus aureus, Kocuria koreensis, Aeromonas hydrophila and Micrococcus luteus.

[0008] Synthetic antimicrobial peptides are extremely stable to temperature and pH treatment.

[0009] The advantages of the present invention are:

[0010] The main advantage of the present invention is that the designed antimicrobial peptide has obvious antibacterial effect on different bacteria (Escherichia coli, Staphylococcus aureus, Coxsackie syndrome, Aeromonas hydrophila and Micrococcus luteus), and the antimicrobial peptide has strong stability to temperature and pH, and can be used to fight bacterial infections. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Physicochemical properties of the antimicrobial peptide.

[0012] Figure 2 The antibacterial effect of this antimicrobial peptide on different bacteria.

[0013] Figure 3 The temperature and pH stability diagram of the antimicrobial peptide, wherein A is the stability diagram of the antimicrobial peptide at different temperatures, and B is the stability diagram of the antimicrobial peptide at pH. DETAILED DESCRIPTION

[0014] The present invention is further described below in conjunction with the examples. The examples are intended to illustrate the present invention, but are not intended to limit the present invention in any form.

[0015] Example 1

[0016] The amino acid sequence in the antimicrobial peptide sequence list SEQ ID No.1.

[0017] Sequence Listing SEQ ID No. 1 is: LWGLLKKGLGKLGRLLKGLLRGK

[0018] (a) Sequence characteristics:

[0019] Length: 23

[0020] Type: Amino acid sequence

[0021] Chain type: Single chain

[0022] Topology: Linear

[0023] (b) Molecule type: protein

[0024] (c) Assumption: No

[0025] (d) Antonym: No

[0026] (e) Original source: artificial synthesis (the present invention is synthesized by Shanghai Bioengineering Co., Ltd.)

[0027] The physicochemical properties of the antimicrobial peptide were predicted using the website heliquest. The positive charge was 7 and the hydrophobicity was 0.46, as shown in Table 1 and Figure 1 .

[0028] Example 2

[0029] Application of the antibacterial effect of the antimicrobial peptide

[0030] Step (1) Antibacterial effect of antimicrobial peptides

[0031] Escherichia coli, Staphylococcus aureus, Coxsackie syndrome, Aeromonas hydrophila and Micrococcus luteus were cultured in LB liquid culture medium to an OD600 of 0.8, and these bacteria were diluted to 10,000 times with LB liquid culture medium. 100 μL of these diluted bacteria were evenly spread on the plate of LB solid culture medium. After the bacteria on the plate were placed in the clean bench and dried, two holes were made at both ends of the plate (a line was drawn in the middle of the plate as the center line, and the two ends were only 1 cm away from the center line) with the white tip of a pipette, and the dry powder of the synthetic antimicrobial peptide was diluted with water to 1 mg / ml. Then 100 μL of antimicrobial peptide was added to the well, and 100 μL of water was added to the control well. It was placed in a 37°C incubator for 12h-14h, and the antibacterial effect was observed the next day. It was found that it had a significant antibacterial effect on Escherichia coli, Staphylococcus aureus, Coxsackie syndrome, Aeromonas hydrophila and Micrococcus luteus, forming an antibacterial circle, such as Figure 2 .

[0032] The LB components are calculated by weight percentage: 1.0% peptone, 0.5% yeast powder, 1.0% sodium chloride, and 97.5% distilled water.

[0033] The Escherichia coli, Staphylococcus aureus, Coxsackie's bacillus, Aeromonas hydrophila and Micrococcus luteus were all purchased from the market and then stored in the laboratory.

[0034] Example 3

[0035] Stability of antimicrobial peptides

[0036] The synthesized antimicrobial peptide powder was diluted with water to a concentration of 1 mg / ml, and the diluted antimicrobial peptide was packaged into 100 μL tubes. Each tube of antimicrobial peptide was treated at different temperatures (4°C, 25°C, 37°C, 65°C, 90°C) for 1 hour. After that, each tube of antimicrobial peptide treated at different temperatures was subjected to antibacterial experiments according to the method of Example 2 above. Escherichia coli was mainly used as an example. The results showed that there was an obvious antibacterial effect, indicating that temperature would not change its activity. Figure 3 A in the above. The synthetic antimicrobial peptide dry powder was diluted to 1 mg / ml using different pH solutions (2, 4, 6, 8, 10) and then the antibacterial peptide concentration was tested according to the method of Example 2. The results showed that it had an antibacterial effect, indicating that pH would not change its activity. Figure 3 B in.

[0037] These results indicate that the antimicrobial peptide has a highly effective antibacterial effect and stability. At a temperature of 4°C-90°C and a pH of 2-10, it can be seen that the antimicrobial peptide of the present invention can be used to prevent and treat bacterial diseases related to Escherichia coli, Staphylococcus aureus, Coxsackie syndrome, Aeromonas hydrophila and Micrococcus luteus, and is stable.

[0038] Table 1 Physicochemical properties of the antimicrobial peptides.

[0039]

Claims

1. An antimicrobial peptide, characterized in that: The sequence of the antimicrobial peptide is shown in the amino acid sequence of SEQ ID No.

1.

2. A use of the antimicrobial peptide according to claim 1, characterized in that: The use of the antimicrobial peptide in the preparation of a bacterial infection inhibitor is used to resist bacterial infection; the bacteria is Escherichia coli ( Escherichia coli ), Staphylococcus aureus ( Staphylococcus aureus )、Coxiella Kocuria koreensis )、Aeromonas hydrophila( Aeromonas hydrophila ) and Micrococcus luteus ( Micrococcus luteus ) one or more of the following.

Images