Peptide antibiotics: an alternative and effective antimicrobial strategy to circumvent fungal infections.
ABSTRACT Mycosis, caused by both filamentous fungi and pathogenic yeasts is a major concern nowadays especially in the immunocompromised patient population. The emergence of pathogenic fungi resistant to current therapies in the last few decades has intensified the search for new antifungals like cationic peptides, which are the key components of innate defense mechanism. The review provides an inventory of different peptides from a diverse array of organisms from bacteria to mammals with proven antifungal activity, their therapeutic options and also about those which are in various stages of preclinical development. Literature, on the total and semi-synthetic variants of the parent peptides that exhibit an improved antifungal activity is also reviewed.
SourceAvailable from: Francisco Miguel Gama[Show abstract] [Hide abstract]
ABSTRACT: Cationic antimicrobial peptides (AMPs) represent the first line of defense against many invading pathogens. These small amphipathic peptides are part of the innate immune system and have a broad-spectrum activity against bacteria, fungi and viruses. In mammals, at least two distinct groups of AMPs are found. Defensins are the more representatives and cathelicidins form the second group. The hCAP18/LL37 is the only known human cathelicidin. The antimicrobial peptide is referred to as LL37, since it has a 37 amino acids sequence starting with two leucines. It is a 4.5 kDa, cationic (+6), amphipathic α-helical peptide, with a broad spectrum of antimicrobial activity. Besides its antimicrobial properties LL37 plays a central role in innate immune responses and inflammation. It has been identified as a potent chemoattractant for mast cells, monocytes, T lymphocytes and neutrophils using formyl-peptide receptor–like 1 (FPRL1). LL37 also promotes wound healing, angiogenesis and arteriogenesis and acts as immune adjuvant.
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ABSTRACT: The aim of this study was determine the antimicrobial activity against several bacteria and yeasts of coriander (Coriander sativum) and parsley (Petroselinum crispum) essential oils (EOs) encapsulated in β-cyclodextrin. The encapsulated EOs were individually tested against several bacteria and yeast using colorimetric broth microdilution method. All species were supplied by the Spanish Type Culture Collection (CECT) of the University of Valencia. Both coriander and parsley encapsulated EO had a very similar antibacterial activity against all the tested strains, with MIC values ranged between 10 and 20 mg/mL. Y. lipolytica showed lower MIC values (5 mg/mL) for both encapsulated EOs than S. cerevisiae and C. Zeylanoides (10 mg/mL).This study showed that both coriander and parsley encapsulates EOs might be a good alternative, as natural antimicrobial agents, to the actual synthetic compounds used in Food industry. However more studies must be done in order to have a better evaluation on the antimicrobial activity.Worldwide Research Efforts in the Fighting Against Microbial Pathogens, ICAR Conference Series edited by A. Mendez-Vilas, 11/2013: chapter In Vitro antimicrobial properties of coriander (Coriandrum sativum) and parsley (Petroselinum crispum) essential oils encapsulated in β-cyclodextrin: pages 168-171; Brownwalker Press., ISBN: 978-1-61233-636-7
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ABSTRACT: The solid-phase conjugation of the antimicrobial peptide c(KKLKKFKKLQ) (BPC194) to a linear or cyclic sequence through a 1,2,3-triazole ring is described. Cyclic alkynyl-peptidyl resins derived from BPC194 were treated with azidopeptides derived from the antimicrobial peptide BP100 or from the bacteriocin iturin A. The cyclic alkynyl-peptidyl resins incorporated at the 3-position a propargylglycine, a glutamic acid residue derivatized with propargylamine or a lysine bearing a propioloyl group. The reactions of the cyclic alkynyl resins with the BP100-derived azidopeptides depended on the length and the sequence of the azidopeptides. The reactions were performed by treatment of the alkynyl resin with CuI and ascorbic acid, and required the presence of piperidine/DMF or DIEA in 2,6-lutidine/DMF. The latter conditions also allowed the conjugation of the alkynyl-peptidyl resin bearing a propioloyl lysine to a linear or cyclic azidopeptide derived from the cyclic moiety of iturin A.European Journal of Organic Chemistry 01/2015; 2015(5). DOI:10.1002/ejoc.201403344 · 3.15 Impact Factor