Class I and II Bacteriocins: Structure, Biosynthesis and Drug Delivery Systems for the Improvement of their Antimicrobial Activity

The increasing emergence of antibiotic resistant pathogens has led to the search for new antimicrobials that can be used in the clinical settings. One such example is represented by bacteriocins which are a heterogenous group of antimicrobial peptides. They are classified into four groups based on their structure, molecular mass, thermostability, enzymatic susceptibility and mechanism of action. Administered alone or in combination with antibiotics, bacteriocins may represent a promising strategy to control infections and also to reduce the risk of food contamination. However, their use for such applications is still limited by the lack of appropriate delivery systems. This review summarizes aspects regarding the molecular structure of the first two classes of bacteriocins, i.e. lantibiotics and non-lantibiotics and their biosynthesis stages and regulation. Furthermore, we highlight the contribution of nanotechnology for optimising bacteriocins in regards to their antimicrobial activity, controlled release and protection from proteolysis.