阅读说明：本技术 一种自组装抗菌肽水凝胶 (Self-assembled antibacterial peptide hydrogel ) 是由 谢燕燕 秦晓彤 钟成 贾士儒 于 2019-09-29 设计创作，主要内容包括：本发明提供了一种自组装抗菌肽水凝胶,属于自组装多肽领域。该自组装抗菌肽序列为C<Sub>16</Sub>-Leu-Leu-Leu-Leu-Arg-Arg-Arg-Arg,其中,Leu为缬氨酸,Arg为精氨酸。是一种阳离子型两亲性多肽。本发明自组装抗菌肽具有良好的自组装能力,且本发明对革兰氏阴性菌和革兰氏阳性菌都具有抑菌效果。(The invention provides a self-assembled antibacterial peptide hydrogel, and belongs to the field of self-assembled polypeptides. The sequence of the self-assembly antibacterial peptide is C 16 -Leu-Leu-Leu-Leu-Arg-Arg-Arg, wherein Leu is valine and Arg is arginine. Is a cationic amphiphilic polypeptide. The self-assembly antibacterial peptide has good self-assembly capability, and has antibacterial effect on gram-negative bacteria and gram-positive bacteria.)

1. The self-assembled antibacterial peptide hydrogel is characterized in that the sequence of the self-assembled antibacterial peptide hydrogel is as follows: c₁₆-Leu-Leu-Leu-Leu-Arg-Arg-Arg-Arg, the self-assembled antibacterial peptide hydrogel having the following structure:

wherein, C₁₆Is an alkyl chain consisting of 16 carbon atoms, Leu is leucine and Arg is arginine.

2. The self-assembling antimicrobial peptide hydrogel of claim 1, wherein the hydrophobic amino acid residue of the self-assembling antimicrobial hydrogel is Leu and the electropositive amino acid residue is Arg.

3. The method for preparing the self-assembled antibacterial hydrogel according to claim 1, wherein the self-assembled antibacterial peptide is dissolved in ultrapure water to a concentration of 2.5-15mg/ml, and a dilute NaOH solution is added dropwise until the solution is clear, and the solution is shaken while being added dropwise, so that the self-assembled antibacterial peptide is self-assembled into nanofibers with a diameter of about 10 nm.

4. A composition comprising the self-assembling antimicrobial peptide hydrogel of claim 1.

5. The composition of claim 4, wherein the self-assembled antimicrobial hydrogel has good inhibitory activity against the growth of gram-negative and gram-positive bacteria at a concentration of 0.5 mg/ml.

6. The composition of claim 5, wherein the gram negative bacteria is E.coli and the gram positive bacteria is S.aureus.

Technical Field

The invention relates to the field of self-assembly polypeptides, in particular to a cationic amphiphilic self-assembly antibacterial peptide.

Background

In recent years, with the abuse of antibiotics, the drug resistance of bacteria is continuously strengthened, the treatment effect is seriously influenced, and the search for novel antibacterial materials is difficult and slow.

Antimicrobial peptides, a peptide-like active substance produced in the biological defense system to combat the invasion of pathogenic microorganisms, typically do not exceed 60 amino acids. Due to the characteristics of wide antibacterial spectrum, unique action mechanism, difficult drug resistance and the like, the antibacterial agent becomes a novel antibacterial agent with great development prospect. However, most natural antibacterial peptides have the problems of direct hemolytic action, weak antibacterial activity, poor stability under physiological conditions, high synthesis cost and the like, and the development of the medicines is restricted to a certain extent.

Molecular self-assembly refers to the process by which molecules spontaneously organize through non-covalent interactions to form aggregates with specific structures and functions under certain conditions. Polypeptide molecules can self-assemble into various highly ordered nanostructures such as nanorods, nanobelts, nanotubes, nanoparticles, nanospheres/capsules, nanospirals, gel fibers, and the like. The nano structure formed by self-assembly of the antibacterial short peptide molecules breaks and dies cells through physical damage to cell membranes, so that drug resistance is not easy to generate, and hemolytic effect is effectively reduced.

Currently, a variety of self-assembling antimicrobial peptides are developed and used in a variety of contexts including bioscaffolds, drug delivery, hemostasis, and antisepsis. However, at the present stage, people do not know the relationship between the structure and the activity of the self-assembled antibacterial peptide deeply, and how to develop an efficient and high-selectivity antibacterial medicament through the modification and design of peptide molecules is also a difficult problem.

Disclosure of Invention

The invention aims to provide an antibacterial peptide hydrogel capable of self-assembling, which has good self-assembling capability and has inhibition on gram-negative bacteria and gram-positive bacteria.

The self-assembled antibacterial peptide hydrogel is characterized in that the sequence of the self-assembled antibacterial peptide hydrogel is as follows: c₁₆-Leu-Leu-Leu-Leu-Arg-Arg-Arg-Arg, the self-assembled antibacterial peptide hydrogel having the following structure:

wherein, C₁₆Is an alkyl chain consisting of 16 carbon atoms, Leu is leucine and Arg is arginine.

In the self-assembled antibacterial peptide hydrogel structure, the hydrophobic amino acid residue is Leu, and the electropositive amino acid residue is Arg.

Dissolving the self-assembly antibacterial peptide in ultrapure water, wherein the concentration is 2.5-15mg/ml, dropwise adding a NaOH dilute solution until the solution is clear, and oscillating while dropwise adding, so that the self-assembly antibacterial peptide is self-assembled into the nano-fiber with the diameter of about 10 nm.

In another aspect of the invention, a composition is provided, which comprises the above-described antimicrobial peptide hydrogel.

In the composition, the self-assembled antibacterial hydrogel has good inhibition on the growth of gram-negative bacteria and gram-positive bacteria at the concentration of 0.5 mg/ml.

The composition of claim 5, wherein the gram negative bacteria is E.coli and the gram positive bacteria is S.aureus.

The invention has the beneficial effects that:

(1) compared with the traditional antibacterial peptide, the self-assembled antibacterial peptide hydrogel disclosed by the invention has an antibacterial effect on gram-negative bacteria and gram-positive bacteria, realizes double bacteriostasis and has good biocompatibility.

(2) The preparation method adopted by the invention has the advantages of simple system, rapid reaction and no need of additionally adding auxiliary gelling factors.

Drawings

FIG. 1 is a diagram of a self-assembled antibacterial peptide hydrogel of the present invention

FIG. 2 is a transmission electron microscope representation of the self-assembled antibacterial peptide hydrogel of the present invention

FIG. 3 is a graph showing the survival rate of E.coli in the presence of self-assembled antibacterial peptide hydrogel

FIG. 4 is a graph showing the survival rate characterization results of Staphylococcus aureus S.aeures in the presence of self-assembled antimicrobial peptide hydrogel

Detailed Description

The present invention will be described below with reference to specific embodiments, but the present invention is not limited to these.

The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, biomaterials, etc. used in the following examples are commercially available unless otherwise specified.

C used in the following examples₁₆-Leu-Leu-Leu-Leu-Arg-Arg-Arg-Arg, synthesized by Gill Biochemical Co., Ltd, Shanghai. The preparation method of the PBS solution with the pH of 7.4 comprises the steps of weighing 3.58g of disodium hydrogen phosphate dodecahydrate, 0.27g of potassium dihydrogen phosphate, 8g of sodium chloride and 0.2g of potassium chloride, dissolving in distilled water, and fixing the volume to 1000 mL.