Proteins are produced in cells in the form of hormones and signal molecules and have a significant influence on the functioning of organs and the whole organism. Nature gives us an abundant source of proteins, which we use as a source of nutrition and energy. Some natural proteins have an antimicrobial effect. Many organisms such as bacteria, animals, plants and humans produce antimicrobial peptides/proteins (AMP) which can fight against microbes. These proteins act as an important part of the immune system.
Antibiotic Proteins: Appearance
These antibiotic proteins are relatively small and consist of 10 to 50 amino acids. Their main characteristic is the occurrence of positively charged amino acids in their sequences, such as lysine and arginine. The proteins are amphiphilic, which means that they possess hydrophilic and hydrophobic residues or sites. While charged residues represent the hydrophilic area of the proteins, the hydrophobic surface contains mostly leucine, isoleucine, alanine and valine. More than half of the proteins display hydrophobic amino acids. The structure of antimicrobial proteins mainly derives from α-helix, β-strand or β-hairpins.
The general mechanism of AMPs has been studied extensively over the years. Research demonstrates the structure, function, and mechanism are spectroscopic techniques such as NMR, CD (circular dichroism), electrophysiological experiments on lipid membranes or fluorescent dyes.