Search results for "Antimicrobial Peptide"
showing 10 items of 89 documents
Echinoderm Antimicrobial Peptides: The Ancient Arms of the Deuterostome Innate Immune System
2016
Antimicrobial peptides (AMPs) are widely expressed in organisms and have been linked to innate and acquired immunity in vertebrates. These compounds are constitutively expressed from different cellular types to interact directly with infectious agents and/or modulate immunoreactions. In invertebrates, including echinoderms, which lack a vertebrate-type adaptive immune system, AMPs represent the major humoral defense system against infection, showing a diverse spectrum of action mechanisms, most of them related to plasma membrane disturbance and lethal alteration of microbial integrity. Here, we summarize the knowledge of AMPs in echinoderms as Strongylocins identified in the sea urchins, St…
FRAGMENTS OF BETA-THYMOSIN FROM THE SEA-URCHIN PARACENTROTUS LIVIDUS AS NOVEL ANTIMICROBIAL PEPTIDES AGAINST STAPHYLOCOCCAL BIOFILMS
2012
With the aim to face the threat of pathogen biofilms intrinsically resistant to conventional antibiotics, we focused on coelomocytes, the immune mediators in echinoderms, as source of novel antimicrobial peptides (AMPs). The proteic fraction <5kDa from coelomocytes cytosol of the sea-urchin Paracentrotus lividus (5-CC) was tested against a group of Gram positive and Gram negative pathogen reference strains. The 5-CC of P. lividus resulted active against all tested strains at concentrations ranging from 15.8 to 253.7 mg/mL. The ability to prevent staphylococcal biofilm formation was evaluated against the biofilm of clinical strain S.epidermidis 1457 using live/dead staining in combination wi…
Mollusk antimicrobial peptides A review from activity-based evidences to computer-assisted sequences
2011
Antimicrobial peptides (AMPs) represent the most universal immune effectors. Molluscs constitute the second largest animal phylum, after Arthropods, in term of number of species. Only a negligible number has been investigated regarding AMPs. The choice of the species to be studied relied on their economical importance and availability. First studies on molluscan AMPs dated from 1996 and were based on biological activities of biochemical-purified fractions. Such approach released all the original structures we know, with biological activity sometimes different from one isoform to another. Then, molecular biology techniques were applied to molluscan AMPs starting in 1999. Complete screening o…
Identification of antimicrobial peptides in the gonad of European sea bass males and females
2015
In vertebrates, the gonad is considered an immunologically privileged site as it triggers lower immune responses aiming to avoid germ cell damage. In fish,several studies reported that leucocytes show conditioned immune response and modulate some reproductive functions, allowing the pathogen to establish chronic and latent infections into reproductive organs. In mammals, antimicrobial peptides (AMPs) have recently been recognised as important effectors in male reproductive tract immunity. In fish, AMPs are increasingly recognized as a critical first line of defence against many pathogens as bacteria, fungi, virus, protozoa and even tumour cells. We have recently determined that the European…
Role of the virulence plasmid pR99 and the metalloprotease Vvp in resistance of Vibrio vulnificus serovar E to eel innate immunity
2007
Vibrio vulnificus biotype 2 serovar E (VSE) is a bacterial pathogen that produces a haemorrhagic septicaemia called vibriosis in eels. Its ability to grow in blood is conferred by a recently described virulence plasmid [Lee CT, Amaro C, Wu KM, Valiente E, Chang YF, Tsai SF, et al. A common virulence plasmid in biotype 2 Vibrio vulnificus and its dissemination aided by a conjugal plasmid. Journal of Bacteriology, submitted for publication.]. In this study, we analyzed the role of this plasmid together with the role played by the metalloprotease (Vvp) in the interaction between bacteria and eel innate immunity. To this end, we compared and statistically analyzed the differences in resistance …
BIOACTIVE MOLECULES FROM MARINE INVERTEBRATE ORGANISMS AS POTENTIAL TOOLS IN RESTORATION PROCEDURES
2013
In the last decades molecular biology has provided innovative approaches in order to set up specific protocols for the conservation and restoration of cultural assets. In this study, which falls within the so called field of Blue-biotechnology, new bio-reactive peptides isolated from marine invertebrate organisrns (Cnidaria and Molluscs) were tested aim to bio-cleaning (proteolytic- peptides) the surfaces or to control (antimicrobial-peptides) the colonization of historic-artistic manufacts by fungi or bacteria. Particularly, the proteolytic-peptides showed hydrolytic activity, specific for animal-glue, in a range of temperatures of 4-37°C; than acting without heating the surface, by a cont…
Marine organisms as source of bioactive molecules applied in restoration projects
2015
Abstract In recent decades research in the conservation and restoration field has provided sustainable alternatives to traditional procedures for cleaning or controlling the microbial colonization of works of art. In the present study, for the first time novel bioactive molecules extracted from marine invertebrate organisms (Anthozoa) were tested instead of chemical compounds for removing protein layers or as a biocide for controlling fungal or bacterial colonization. In particular, Bioactive Molecules with Protease activity (BMP), acting in a temperature range of 4- 30°C, were tested for the hydrolysis of protein layers on laboratory specimens. The cleaning protocol provides a selective pr…
Of Cockroaches and Symbionts: Recent Advances in the Characterization of the Relationship between Blattella germanica and Its Dual Symbiotic System
2022
This article belongs to the Collection Feature Review Papers for Life.
Comparison of the activity of antifungal hexapeptides and the fungicides thiabendazole and imazalil against postharvest fungal pathogens
2003
8 pages, 2 figures, 3 tables.-- PMID: 14623382 [PubMed].-- Printed version published Dec 31, 2003.
Old Weapons for New Wars: Bioactive Molecules From Cnidarian Internal Defense Systems
2016
The renewed interest in the study of genes of immunity in Cnidaria has led to additional information to the scenario of the first stages of immunity evolution revealing the cellular processes involved in symbiosis, in the regulation of homeostasis and in the fight against infections. The recent study with new molecular and functional approach on these organisms have therefore contributed with unexpected information on the knowledge of the stages of capturing activities and defense mechanisms strongly associated with toxin production. Cnidarians are diblastic aquatic animals with radial symmetry; they represent the ancestral state of Metazoa, they are the simplest multicellular organisms tha…