The hinge structure, also known as hinge region or bend, is a special structure found in some antimicrobial peptides. Most studies on antimicrobial peptides focused on the standard secondary structure of α-helix and β-sheet, while the hinge structure and its functions were rarely studied. The hinge structure confers the antimicrobial peptides an improved structural flexibility, which may promote their disruptive effect on bacterial membrane or their binding efficiency to the intracellular targets, thus resulting in a higher antibacterial activity. Meanwhile, the hinge structure may reduce the structural rigidity, which may eliminate the cytotoxicity of antimicrobial peptides to eukaryotic cells. This article reviews the structural characteristics of the hinge structure, its effects on the biological activity of antimicrobial peptides and application in the molecular design, with the aim to provide a reference for the design and development of new antimicrobial peptides.
Anti-Bacterial Agents/pharmacology* ; Anti-Infective Agents/pharmacology* ; Antimicrobial Cationic Peptides/pharmacology* ; Pore Forming Cytotoxic Proteins ; Protein Structure, Secondary