Antibacterial Proline-Rich Oligopeptides and Their Target Proteins

This review presents findings on a new family of antibacterial proline-rich oligopeptides—pyrrhocoricin, drosocin, apidaecin, and formaecin—isolated from insects. The functional and physicochemical properties of proline-rich oligopeptides are considered, a role of proline in their antibacterial activity is discussed, and experimental evidence is given in favor of the ability of these oligopeptides to suppress metabolism of bacteria by means of stereospecific interaction with heat shock protein DnaK and inhibition of DnaK-dependent protein folding. Binding of the peptides under investigation with DnaK correlates with their antibacterial activity. Evidence that pyrrhocoricin, drosocin, apidaecin, and formaecin are nontoxic for human and animal cells serves as a prerequisite for their use as novel antibiotic drugs.