Design, Synthesis and Applications of Antimicrobial Peptides and Antimicrobial Peptide-Mimetic Copolymers

Antibiotics resistance of bacteria has caused serious threats to public health and it is urgent to develop novel antibacterial agents that do not induce drug-resistance. Antimicrobial peptides (AMPs), constituting important parts of the immune system, are cationic short peptides produced by most living creatures such as bacteria, plants, fish, insects, mammal animals and so on. AMPs possess many excellent properties, including broad-spectrum antibacterial efficacy, high selectivity and unique membrane-destruction bactericidal mechanism. Thus, AMPs have become a promising candidate to overcome superbugs. However, over-costing and time-consuming production of natural AMPs limit their large-scale application. Therefore, low-cost and convenient synthesis methods have emerged, such as liquid-phase synthesis, solid-phase synthesis and N-carboxyanhydrides (NCA) ring-opening polymerization. Meanwhile, novel peptide-mimetic antibacterial polymers provide unlimited possibilities for development of peptide-based antibacterial agents and broaden their application fields. In this review, the sources, structure and antibacterial mechanism of AMPs are introduced. The synthesis methods to date of AMPs are also reviewed. Moreover, the development of antimicrobial peptide-mimetic copolymers and application of their assemblies are summarized as well. Finally, the shortcomings and the further development of antimicrobial peptides are discussed, providing advice for development of efficient, low toxicity "new generation antibiotic" in the future.