Abstract
Bacterial resistant to antibiotics is a global health problem that necessitates the production of new effective therapeutics. Antimicrobial peptides (AMPs) are commonly accepted as viable alternatives to currently used antibiotics. Some AMPs have the ability to work against not only planktonic bacteria but microbial biofilms as well. Proline rich antimicrobial peptides (PR-AMPs) are a distinctive group of AMPs, isolated in various animal sources, exhibiting an exceptionally high proline content. PR-AMPs function through non-lytic mechanisms and are generally regarded as non-toxic to mammalian cells. These peptides block bacterial protein translation by binding on and inactivating the ribosome. Proline, the only cyclic proteinogenic amino acid has the ability to undergo cis-trans isomerisation. When two different pyrrolidine ring conformations (exo and endo pucker) are adopted, these rotational isomers along the peptidyl-proline bond have different stabilities. Protein structure has ability to regulate itself either by preferring unique conformations and by improving hydrophobic interactions. Pseudoprolines (ΨPro) are mimetics of proline and function as molecular hinges. These ΨPro can be used for tailoring cis / trans isomerization around the Xaa- ΨPro amide bond (Xaa can be any amino acid) and hydrophobicity modulation.

Key words: Antimicrobial resistance, Antimicrobial peptides, Proline-rich antimicrobial peptides, Proline, cis-trans isomerization, pseudoproline