Antimicrobial peptides naturally occurring

Peptides are long, continuous and unbranched chain polymers formed by the polymerisation of amino acid monomers. During the polymerisation process two units are linked together via a peptide bond (-CO-NH-), which is formed by the reaction of a carboxylic group (-COOH) of one amino acid and an amino group (-NHi) of another. Peptides naturally occur in animals and plants, and can also be synthesised in the laboratory. Peptides play a significant role in the prevention of bacterial infections and, to date, more than 5,000 antimicrobial peptides (AMP) have been discovered or synthesised. 

Gallo, R.L., Murakami, M., and Zaiou, M., Biology and clinical relevance of naturally occurring antimicrobial peptides. J. Allergy Clin. Immunol. 110, 823, 2003. 

Chitosan, the deacetylated form of chitin, is a plentiful and naturally occurring aminopolysaccharide obtained fl om shellfish and other marine species. Most of the research on applying this to fibers and films has been conducted in Japan and to a lesser extent Korea. Micromilled chitosan powder has been blended with rayon fibers, followed by subsequent lamination, to produce a variety of nonwoven fabrics known as Chitopoly. These modified materials were even effective against a methacillin-strain of S. aureus [37], Numerous other publications and patents describe incorporation of chitosan in various forms to produce antimicrobial fibers and polymers. One of the more recent examples is the binding of a quaternary ammonium derivative of chitosan to cotton fabric to produce an antibacterial finish [38]. The other area of current interest is the use of naturally occurring peptides as antimicrobial agents. The use of combinatorial libraries allows one to systematically examine ten to hundreds of millions of peptides for their antimicrobial activity. This was demonstrated with various strains... 

In recent years, peptoid research has focused on the development of new peptoid-based antimicrobial agents either from de novo design [20-24], cyclic peptoids [25], libraries [26,27], or by transforming naturally occurring antimicrobial peptides into peptoid analogs [28]. 

Hussain, R., Joannou, C.L., Siligardi, G., 2006. Identification and characterization of novel lipophilic antimicrobial peptides derived from naturally occurring proteins. Int. J. PepL Res. Ther. 12, 269-273. http //dx.doi.org/10.1007/sl0989-006-9033A. 

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