scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Antimicrobial peptides isolated from skin secretions of the diploid frog, Xenopus tropicalis (Pipidae).

26 Nov 2001-Biochimica et Biophysica Acta (Biochim Biophys Acta)-Vol. 1550, Iss: 1, pp 81-89
TL;DR: Seven peptides with antimicrobial activity were isolated from norepinephrine-stimulated skin secretions of the diploid clawed frog, Xenopus tropicalis, suggesting that the species are not closely related phylogenetically.
About: This article is published in Biochimica et Biophysica Acta.The article was published on 2001-11-26. It has received 84 citations till now. The article focuses on the topics: Antimicrobial peptides & Peptide sequence.
Citations
More filters
Journal ArticleDOI
TL;DR: This review focuses on AMPs forming α‐helices, β‐hairpin‐like β‐sheets, α‐helix/β‐sheet mixed structures from invertebrate and vertebrate origins, which show some promise for therapeutic use.
Abstract: Gene-encoded anti-microbial peptides (AMPs) are widespread in nature, as they are synthesized by microorganisms as well as by multicellular organisms from both the vegetal and the animal kingdoms. These naturally occurring AMPs form a first line of host defense against pathogens and are involved in innate immunity. Depending on their tissue distribution, AMPs ensure either a systemic or a local protection of the organism against environmental pathogens. They are classified into three major groups: (i) peptides with an alpha-helical conformation (insect cecropins, magainins, etc.), (ii) cyclic and open-ended cyclic peptides with pairs of cysteine residues (defensins, protegrin, etc.), and (iii) peptides with an over-representation of some amino acids (proline rich, histidine rich, etc.). Most AMPs display hydrophobic and cationic properties, have a molecular mass below 25-30 kDa, and adopt an amphipathic structure (alpha-helix, beta-hairpin-like beta-sheet, beta-sheet, or alpha-helix/beta-sheet mixed structures) that is believed to be essential to their anti-microbial action. Interestingly, in recent years, a series of novel AMPs have been discovered as processed forms of large proteins. Despite the extreme diversity in their primary and secondary structures, all natural AMPs have the in vitro particularity to affect a large number of microorganisms (bacteria, fungi, yeast, virus, etc.) with identical or complementary activity spectra. This review focuses on AMPs forming alpha-helices, beta-hairpin-like beta-sheets, beta-sheets, or alpha-helix/beta-sheet mixed structures from invertebrate and vertebrate origins. These molecules show some promise for therapeutic use.

1,012 citations

Journal ArticleDOI
TL;DR: The broad-spectrum antibacterial and antifungal activities of certain peptides, for example esculentin-1, ranalexin-1 and ranatuerin, together with their relatively low hemolytic activity, make them candidates for development into therapeutically useful anti-infective agents.

381 citations

Journal ArticleDOI
TL;DR: Results indicate new possibilities for the development of effective human therapeutics based on antimicrobial peptides and partially disclosed the biotechnological potential of these molecules.

209 citations

Journal ArticleDOI
TL;DR: This review covers the literature on the subject of biologically active peptide from the glands of amphibians, which include neuropeptides, antimicrobial and anticancer active peptides, antiviral agents, fungicides and peptides which complex with Ca2+ calmodulin.

185 citations

Journal ArticleDOI
TL;DR: Data is presented to show that antimicrobial peptides, produced in granular glands of the skin and released in high concentrations into skin secretions, are highly effective in inhibiting growth of B. dendrobatidis in vitro and may provide limited protection for some species.
Abstract: Chytridiomycosis, an emerging infectious disease (EID) of the skin caused by the chytrid fungus, Batrachochytrium dendrobatidis, has been linked with continuing amphibian population declines in the western USA, Central America, Europe, Africa, and Australia. Genetic analysis suggests that B. dendrobatidis is a recently emerged pathogen. This article reviews the biology of this pathogenic chytrid and the evidence for chytridiomycosis as a cause of declines in amphibian populations worldwide. Data are presented to show that antimicrobial peptides, produced in granular glands of the skin and released in high concentrations into skin secretions, are highly effective in inhibiting growth of B. dendrobatidis in vitro and may provide limited protection for some species. Ongoing studies suggest a correlation between resistance to lethal infection by B. dendrobatidis and synthesis of antimicrobial peptides by the host amphibian, but further research is needed to define better the role of antimicrobial peptides in protection of amphibian populations and the effect of environmental factors upon antimicrobial peptide synthesis.

176 citations

References
More filters
Journal ArticleDOI
TL;DR: The algorithm is shown to be at least as good as, and usually superior to, the reported prediction methods assessed in the same way and the implication in protein folding is discussed.

4,360 citations

Journal ArticleDOI
TL;DR: A family of peptides with broad-spectrum antimicrobial activity has been isolated from the skin of the African clawed frog Xenopus laevis and appears to represent a previously unrecognized class of vertebrate antimicrobial activities.
Abstract: A family of peptides with broad-spectrum antimicrobial activity has been isolated from the skin of the African clawed frog Xenopus laevis. It consists of two closely related peptides that are each 23 amino acids and differ by two substitutions. These peptides are water soluble, nonhemolytic at their effective antimicrobial concentrations, and potentially amphiphilic. At low concentrations they inhibit growth of numerous species of bacteria and fungi and induce osmotic lysis of protozoa. The sequence of a partial cDNA of the precursor reveals that both peptides derive from a common larger protein. These peptides appear to represent a previously unrecognized class of vertebrate antimicrobial activities.

2,073 citations

Journal ArticleDOI
TL;DR: Antimicrobial cationic peptides are an important component of the innate defenses of all species of life as discussed by the authors, and different peptides may have antibacterial, anti-endotoxic, antibiotic-potentiating or antifungal properties.

1,347 citations

Journal ArticleDOI
TL;DR: This review considers alpha-helical, antimicrobial peptides from the point of view of six interrelated structural and physicochemical parameters that modulate their activity and specificity: sequence, size, structuring, charge, amphipathicity, and hydrophobicity.
Abstract: Gene-encoded antimicrobial peptides are an important component of host defense in animals ranging from insects to mammals. They do not target specific molecular receptors on the microbial surface, but rather assume amphipathic structures that allow them to interact directly with microbial membranes, which they can rapidly permeabilize. They are thus perceived to be one promising solution to the growing problem of microbial resistance to conventional antibiotics. A particularly abundant and widespread class of antimicrobial peptides are those with amphipathic, alpha-helical domains. Due to their relatively small size and synthetic accessibility, these peptides have been extensively studied and have generated a substantial amount of structure-activity relationship (SAR) data. In this review, alpha-helical antimicrobial peptides are considered from the point of view of six interrelated structural and physicochemical parameters that modulate their activity and specificity: sequence, size, structuring, charge, amphipathicity, and hydrophobicity. It begins by providing an overview of how these vary in peptides from different natural sources. It then analyzes how they relate to the currently accepted model for the mode of action of alpha-helical peptides, and discusses what the numerous SAR studies that have been carried out on these compounds and their analogues can tell us. A comparative analysis of the many alpha-helical, antimicrobial peptide sequences that are now available then provides further information on how these parameters are distributed and interrelated. Finally, the systematic variation of parameters in short model peptides is used to throw light on their role in antimicrobial potency and specificity. The review concludes with some considerations on the potentials and limitations for the development of alpha-helical, antimicrobial peptides as antiinfective agents.

1,182 citations

Journal ArticleDOI
TL;DR: This review, which is focused on magainins, cecropins, and dermaseptins as representatives of the amphipathic alpha-helical antimicrobial peptides, supports the carpet-like rather the barrel-stave mechanism.
Abstract: The increasing resistance of bacteria to conventional antibiotics resulted in a strong effort to develop antimicrobial compounds with new mechanisms of action. Antimicrobial peptides seem to be a promising solution to this problem. Many studies aimed at understanding their mode of action were described in the past few years. The most studied group includes the linear, mostly alpha-helical peptides. Although the exact mechanism by which they kill bacteria is not clearly understood, it has been shown that peptide-lipid interactions leading to membrane permeation play a role in their activity. Membrane permeation by amphipathic alpha-helical peptides can proceed via either one of the two mechanisms: (a) transmembrane pore formation via a "barrel-stave" mechanism; and (b) membrane destruction/solubilization via a "carpet-like" mechanism. The purpose of this review is to summarize recent studies aimed at understanding the mode of action of linear alpha-helical antimicrobial peptides. This review, which is focused on magainins, cecropins, and dermaseptins as representatives of the amphipathic alpha-helical antimicrobial peptides, supports the carpet-like rather the barrel-stave mechanism. That these peptides vary with regard to their length, amino acid composition, and next positive charge, but act via a common mechanism, may imply that other linear antimicrobial peptides that share the same properties also share the same mechanism.

789 citations