Antimicrobial resistance is fast rising to the top of the list of concerns of scientists, and policy makers alike. Antimicrobial resistance is not just limited to drugs aimed at microbes. Every class of antibiotics is affected by antimicrobial resistance including antivirals, antiparasitic and antifungal drugs. Antibacterial drugs were originally isolated from natural sources, but as the threat of antibacterial resistance looms, the development of intelligently designed antimicrobial drugs, including small molecules and custom antimicrobial peptides has been fostered.
Antimicrobial peptides(AMPs) are short peptide ranging from 10 to 50 amino acids and has a broad spectrum of antibiotic activities against bacteria, yeasts, fungi, and viruses, as well as cytotoxic activity on cancer cells, anti-inflammatory, and immunomodulatory activities.
In addition to being a tool for antimicrobial drug development, AMPs are considered as one of the most promising feed additives in swine, poultry and even fish production. As feed additives AMPs show remarkable effects, including: broad spectrum effects, low levels of reduced resistance, improve growth performance and enhance immune function, etc.
The distinct activity of antimicrobial peptides governs their sequence, namely, the incorporation of these peptides into microbial cell membranes. As a result, these sequences usually consist of >50% hydrophobic residues. Due to the negative charge of many microbial membrane components (e.g. phospholipids, lipopolysaccharides and teichonic acids), antimicrobial peptides are often cationic in nature. In addition, they may contain modifications such as cyclization or disulfide bonds.