阅读说明：本技术 含D型脯氨酸和甘氨酸转角的β发卡抗菌肽及制备方法 (β hairpin antibacterial peptide containing D-type proline and glycine corner and preparation method thereof ) 是由 单安山 邵长轩 菅俏 于 2020-03-30 设计创作，主要内容包括：本发明提供一种含D型脯氨酸和甘氨酸转角的β发卡抗菌肽及制备方法。本发明抗菌肽WKFpG其序列如SEQ ID No.1所示。本发明以刚性D-Pro-Gly转角为转角单元,通过在β-发卡侧链的非氢键位点对称放置色氨酸和赖氨酸,利用其交互作用辅助D-Pro-Gly转角形成发卡结构,设计出抗菌肽模板XWYKYZZXWYKY-NH<Sub>2</Sub>。本抗菌肽在制备治疗革兰氏阳性菌或/和革兰氏阴性菌引起的感染性疾病药物中的应用。本抗菌肽氨基酸序列长度仅有12,揭示刚性pG转角对于β-发夹抗菌肽的生物学活性的影响,对多种革兰氏阴性菌和阳性菌具有高效的抑制作用,而且溶血活性较低,治疗指数达到110.30,相较于含有NG转角的相同侧链的β-发卡抗菌肽提高了1.5倍,具有成为绿色高效抗生素替代品的发展潜力。(The invention provides an β hairpin antibacterial peptide containing D-type proline and glycine corner and a preparation method thereof.A sequence of the antibacterial peptide WKFpG is shown as SEQ ID No. 1. the invention takes rigid D-Pro-Gly corner as a corner unit, tryptophan and lysine are symmetrically placed at non-hydrogen bond sites of β -hairpin side chains, and the interaction of the tryptophan and the lysine is utilized to assist the D-Pro-Gly corner to form a hairpin structure, so that an antibacterial peptide template XWYKYZZXWKY-NH is designed 2 . The antibacterial peptide is applied to the preparation of medicaments for treating infectious diseases caused by gram-positive bacteria or/and gram-negative bacteria. The antibacterial agent has antibacterial effectThe length of the peptide amino acid sequence is only 12, the influence of rigid pG corner on the biological activity of β -hairpin antibacterial peptide is revealed, the peptide has high-efficiency inhibition effect on various gram-negative bacteria and gram-positive bacteria, the hemolytic activity is low, the therapeutic index reaches 110.30, the peptide is improved by 1.5 times compared with β -hairpin antibacterial peptide containing the same side chain of NG corner, and the peptide has the development potential of being a green high-efficiency antibiotic substitute.)

1. The β hairpin antibacterial peptide WKFpG is characterized in that the antibacterial peptide WKFpG takes a D-Pro-Gly corner as a corner unit, two pairs of tryptophan and lysine are placed at non-hydrogen bond sites of a β hairpin side chain to assist the D-Pro-Gly corner in forming a hairpin structure, and the amino acid sequence of the antibacterial peptide WKFpG is shown in SEQ ID No. 1.

2. The method for preparing β hairpin antibacterial peptide WKFpG containing D-type proline and glycine turn as claimed in claim 1, wherein rigid D-Pro-Gly turn is used as turn unit, two pairs of tryptophan and lysine are placed at non-hydrogen bond sites of β hairpin side chain, and interaction of tryptophan and lysine is used to assist D-Pro-Gly turn to form hairpin structure, so as to design antibacterial peptide template XWYKYZZXWYKY-NH₂When X ═ R, Y ═ F, ZZ ═ pG, the antimicrobial peptide was named WKFpG, and its amino acid sequence was shown in SEQ ID No. 1.

3. The application of the β hairpin antibacterial peptide WKFpG containing D-proline and glycine turn as claimed in claim 1, wherein the application is in the preparation of medicine for treating infectious diseases caused by gram-positive bacteria or gram-negative bacteria.

Technical Field

The invention belongs to the technical field of biology, and particularly relates to β hairpin antibacterial peptide containing D-type proline and glycine turn and a preparation method thereof.

Background

Over the past few decades, the overuse and improper use of antibiotics has prompted the emergence of drug residues and bacterial resistance, which raises serious global health concerns and contributes to a reduction in the economic output of animal production or other industries. The search for new therapeutic strategies has become an urgent necessity. Antimicrobial peptides (AMPs) play an inherent role as the first line of host defense in almost all multicellular organisms, exhibiting inhibitory activity against a variety of pathogens. Although various targets of action of AMPs in bacteria have been reported in recent years, it is needless to say that most AMPs insert their hydrophobic domains into the cytoplasmic membrane after electrostatic interaction between their cationic domains and negatively charged lipids on the surface of the bacteria. This non-receptor membrane lysis mechanism makes bacteria unfavorable for the development of resistance to AMPs. AMPs are therefore considered important competitors for antibiotic alternatives.

To date, antimicrobial peptide databases have contained 3,000 AMPs from bacteria, archaea, protists, fungi, plants and animals, but the use of these AMPs isolated from natural sources is generally limited by their sequence length, lack of efficacy and excessive cytotoxicity, in all stages of AMPs development, researchers have invented a series of approaches, such as sequence truncation, motif hybridization and amino acid replacement, to address these difficulties, but these studies have been limited by the immobility and complexity of the parent peptide template, to the hard-to-understand and effective disclosure of the structural functional relationships of antimicrobial peptides, while most of the past few decades of antimicrobial peptide studies have been directed to linear α helical antimicrobial peptides, β -folded antimicrobial peptides are too long because of their complex structural composition and the disulfide bonds that are difficult to achieve in production, have not been studied extensively, and the design of short β -structural 630-structural functional relationships to study the structural functional relationships of linear 4834-folded antimicrobial peptides and the structural functional relationships of the currently available single-fold hairpin peptides-685 peptides with a less effective structural configuration, as well as the most efficient anti-structural modifications of the anti-structural activities of the hairpin peptides-wo-9-structural modifications of the current hairpin peptide-9-structural modifications, no obvious structural activities of the structural modifications of the current antimicrobial peptides, no obvious structural modifications of the structural activity of the structural modifications of the current structural modifications of the structural modifications of.

Disclosure of Invention

Based on the defects, the invention provides β hairpin antibacterial peptide containing D-type proline and glycine corner and a preparation method thereof, and solves the problems of overlong sequence, high toxicity, difficult synthesis, high synthesis cost and the like in the preparation process of β -folded antibacterial peptide.

The technical scheme includes that the β hairpin antibacterial peptide WKFpG containing D-type proline and glycine corner takes D-Pro-Gly corner as a corner unit, two pairs of tryptophan and lysine are placed at non-hydrogen bond sites of a hairpin side chain β, interaction of the tryptophan and the lysine is utilized to assist the D-Pro-Gly corner to form a hairpin structure, and the amino acid sequence of the hairpin structure is shown in SEQ ID No. 1.

The invention also discloses a preparation method of the β hairpin antibacterial peptide WKFpG containing the D-type proline and glycine corner, which is technically characterized in that a rigid D-Pro-Gly corner is used as a corner unit, two pairs of tryptophan and lysine are placed at non-hydrogen bond sites of a β hairpin side chain, and the interaction of the two pairs of tryptophan and lysine is utilized to assist the D-Pro-Gly corner to form a hairpin structure, so that an antibacterial peptide template XWYKYZZXWYKY-NH is designed₂When X ═ R, Y ═ F, ZZ ═ pG, the amino acid sequence is shown in SEQ ID No. 1.

The invention also aims to provide application of the β hairpin antibacterial peptide WKFpG containing the D-type proline and the glycine turn in preparing a medicament for treating infectious diseases caused by gram-positive bacteria or/and gram-negative bacteria.

The antibacterial peptide prepared by the method has the beneficial effects and advantages that the antibacterial peptide is stable in structure and short in sequence length, does not contain disulfide bonds which are difficult to realize in antibacterial peptide production, is simple in preparation technology, can be used for carrying out antibacterial and hemolytic activity detection on the obtained antibacterial peptide, and finds that WKFpG has a high-efficiency inhibiting effect on various strains such as escherichia coli, pseudomonas aeruginosa, salmonella typhimurium, staphylococcus aureus, staphylococcus epidermidis, enterococcus faecalis and the like, has a geometric mean of the inhibiting activities of ten kinds of bacteria of 4.64, has very low hemolytic activity, has a treatment index of 110.30, is improved by 1.5 times compared with β -hairpin antibacterial peptide containing the same side chain of an NG corner, and shows that a D-type proline glycine corner is favorable for improving the antibacterial activity of the antibacterial peptide.

Drawings

FIG. 1 is a high performance liquid chromatogram of antimicrobial peptide WKFpG;

FIG. 2 is a mass spectrum of the antimicrobial peptide WKFpG.

Detailed Description

The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.