BOC Sciences provides an extensive selection of antimicrobial peptides and has the capability to customize peptides according to the specific needs of customers. Antimicrobial peptides (AMPs) are a class of natural defense molecules found in many organisms. AMPs are small molecular peptide chains consisting of 10-50 amino acids that are cationic and hydrophilic antimicrobial peptides are a variety of peptides that have inhibitory or bactericidal activity in vivo, most of which are alkaline and have good thermal stability. AMPs can kill or inhibit the growth of microorganisms through a variety of mechanisms, including disrupting cell membranes, inhibiting cell wall synthesis, and interfering with nucleic acid and protein synthesis.
Fig.1 Classification of antimicrobial peptides. (Huan et al., 2020)
Antimicrobial peptides are manifold according to their structural features. Statistics show that the highest percentage of antimicrobial peptides are those containing disulfide bridge structures, followed by those with α-helix and β-fold as well as both structures. However, the structures of a considerable proportion of antimicrobial peptides remain unknown. Among them, α-helical peptides are widely distributed and diverse, with amphiphilic structures in the molecule, and mainly achieve bactericidal effects by changing the permeability and barrier function of the phospholipid bilayer of cell membranes, or by penetrating the membrane interface to destroy the membrane structure. β-folded peptides usually are more structural complex than α-helical antimicrobial peptides, presenting as ring-like molecules with structures of intramolecular disulfide bonds.
AMPs usually have rapid bactericidal action, which can destroy the cell structure and function of microorganisms in a short period of time, leading to the death of microorganisms.
Since AMPs act on multiple targets of microorganisms, including cell membranes, cell walls, and nucleic acids, microbial resistance to antimicrobial peptides is slow to develop.
Many AMPs form pores or channels by interacting with the microbial cell membrane, leading to rupture of the cell membrane and increased permeability. This disrupts the exchange of substances in and out of the cell, leading to cell death.
Certain AMPs can interact with components of the bacterial cell wall such as lipopolysaccharide (LPS) or cholesterol, interfering with bacterial cell wall synthesis and stability.
AMPs can interact with microbial nucleic acids and proteins to interfere with their synthesis processes. They can bind to microbial DNA or RNA, interfering with its replication and transcription processes.
Since AMPs differ from antibiotics in their bactericidal mechanism which shield from producing resistant strains and drug resistance, they have become an ideal substitute for antibiotics. Moreover, AMPs can inhibit wound infection, reduce bacterial growth and inflammatory response, and promote wound repair and healing process.
AMPs can inhibit the growth of bacteria, fungi and parasites in food, extend the shelf life of food, and reduce the risk of microbial contamination and foodborne diseases in food. For example, Nisin is a polycyclic antibacterial peptide produced by Lactococcus lactis, with antagonistic effect on Gram-positive bacteria. Currently, Nisin is widely applied as a natural preservative in food industry.
AMPs can be used to coat medical devices, biomaterials and surfaces to form antimicrobial coatings. Antimicrobial coatings can be applied to medical devices such as urinary catheters, artificial joints, and cardiac stents, as well as materials such as textiles, plastics, and metal surfaces.