Types Of Antimicrobial Peptides

"Pharmacological Reviews" states that tissues and organisms representing every kingdom of life, from plants to insects to humans, have yielded antimicrobial peptides. According to the Journal of the American Academy of Dermatology, the properties of antimicrobial peptides include small proteins less than 100 amino acids in length and usually positively charged.
Harrison's Principles of Internal Medicine notes that these peptides, part of the innate immune system, have broad antimicrobial activity against viruses, bacteria and fungi.

Polymyxin B

According to "Pharmacological Reviews," for many years, antimicrobial peptides have been used to prevent or treat infections. Found in many topical applications, the peptides polymyxin B, gramicidins, and bacitracin offer effective antibacterial coverage.
As stated by The Washington Manual of Medical Therapeutics, polymyxin B given intravenously treats drug-resistant bacteria like Pseudomonas aeruginosa in patients with cystic fibrosis or bronchiectasis, permanent dilatation of bronchi in the lungs.

Defensins and Cathelicidins

Dr. Tomas Ganz wrote in the journal Nature that, in humans and other mammals, defensins and cathelicidins categorize two peptide groups. Patients with atopic dermatitis have deficiencies in these peptides. According to The New England Journal of Medicine, 30 percent of patients with atopic dermatitis have bacterial or viral infections of the skin. However, excess amounts of cathelicidin has been associated with the skin disorder rosacea.

MBI 226

According to The Proceedings of The National Academy of Science, as stated by Dr. Robert Hancock, omiganan pentahydrochloride, or MBI 226, a topical peptide developed by Micrologix Biotech, prevents central venous catheter-related infections due to colonization of a catheter by skin bacteria.

Lantibiotics

Lantibiotics, another type of antimicrobial peptide has attracted attention in recent years due to the success of nisin as a food preservative. Nisin is an antimicrobial protein produced naturally by a bacterium called Lactococcus lactis. The use of nisin has been approved for cheeses, but a large body of information exists on its ability to inhibit pathogenic and spoilage bacteria in many food products. One of the most important and promising applications of nisin involves control of Listeria monocytogenes in ready-to-eat meats.