Antimicrobial Peptides: A Promising Answer to Antimicrobial Resistance

The progressive decline in therapeutic efficacies of the available drugs due to the spread of
antimicrobial resistance emphasizes the need to develop new classes of antimicrobial agents for the
handling of infectious diseases. This urgency has motivated researchers to find out a relatively new
and sustainable weapon to fight against pathogenic microorganisms, called host-defense peptides,
also called antimicrobial peptides (AMPs). Till date more than 3000 natural AMPs have been
discovered from a diverse range of organisms, namely, archaea, protists, fungi, bacteria, plants and
animals. The antimicrobial activity of AMPs can be exerted by killing directly microbial pathogens or
indirectly by modulating the host immune systems. In addition AMPs possess other important
biological roles like anti-biofilm, anticancer and wound healing activities, immunomodulatory and
regenerative properties, or even regulation of gut microbiota. In this chapter, we discuss on the
properties, biological role, classification, and mode of action of AMPs along with different models
explaining the killing mechanism of AMPs. At the end, we shall also discuss the opportunities and
challenges to design these AMPs as novel therapeutics.