Search results for " Defensin"
showing 6 items of 6 documents
αβ defensin antimicrobial peptide (BPDEF) from the invasive red sea mussel Brachidontes pharaonis (P. Fischer, 1870)
2015
The immune system that plays a major role in determining host fitness in the wild, i.e. under the constraints imposed by ecology and life history. Permanent conflict interactions with the environment are the natural situation for a living creature. To partially resolve this, the immune system evolved and is characterized by an enormous variety of mechanisms and effectors, including the AMPs, although their specificity is poor. In fact, AMPs are universal and extremely successful in dealing with a huge range of pathogens, including bacteria, fungi, protozoa and viruses Amps are oligopeptides composed of varying number of amino acids with a broad spectrum of targeted organisms ranging from vi…
Dual Antimicrobial and Antiproliferative Activity of TcPaSK Peptide Derived from a Tribolium castaneum Insect Defensin
2021
Antimicrobial peptides (AMPs) found in the innate immune system of a wide range of organisms might prove useful to fight infections, due to the reported slower development of resistance to AMPs. Increasing the cationicity and keeping moderate hydrophobicity of the AMPs have been described to improve antimicrobial activity. We previously found a peptide derived from the Tribolium castaneum insect defensin 3, exhibiting antrimicrobial activity against several human pathogens. Here, we analyzed the effect against Staphyloccocus aureus of an extended peptide (TcPaSK) containing two additional amino acids, lysine and asparagine, flanking the former peptide fragment in the original insect defensi…
Identification, cloning and environmental factors modulation of a αβ defensin from the lessepsian invasive mussel Brachidontes pharaonis (Bivalvia: M…
2015
International audience; Immunological effectors of invasive species playing a role in addressing new colonization are still poorly studied. In the present study the cDNA sequence of the defensin from a Lessepsian invasive species, the Red Sea mussel Brachidontes pharaonis, was cloned using RACE method. Defensins are a class of widely known antimicrobial peptides (AMPs), oligopeptides with a broad spectrum of targeted organisms ranging from viruses to parasites. Analysis of BpDef sequence (262 bp) revealed the presence of an ORF coding for 81 amino acids. The full-length amino acid sequence showed the highest similarity to antimicrobial peptides MGD1 and MGD2 sequence from Mytilus galloprovi…
Identification of New Antimicrobial Peptides from Mediterranean Medical Plant Charybdis pancration (Steinh.) Speta
2020
The present work was designed to identify and characterize novel antimicrobial peptides (AMPs) from Charybdis pancration (Steinh.) Speta, previously named Urginea maritima, is a Mediterranean plant, well-known for its biological properties in traditional medicine. Polypeptide-enriched extracts from different parts of the plant (roots, leaves and bulb), never studied before, were tested against two relevant pathogens, Staphylococcus aureus and Pseudomonas aeruginosa. With the aim of identifying novel natural AMPs, peptide fraction displaying antimicrobial activity (the bulb) that showed minimum inhibitory concentration (MICs) equal to 30 µ
Polymorphism of mytilin B mRNA is not traslated into mature peptide
2008
Diversity of mRNAs from mytilin B, one of the five mytilins identified in the Mediterranean mussel, Mytilus galloprovincialis, has been investigated from circulating hemocytes. One mussel expressed simultaneously two to ten different mytilin B mRNAs as observed in denaturing gradient gel electrophoresis (DGGE), defining 10 individual DGGE patterns (named A to J) within the mussels from Messina, Sicily (Italy). Three patterns accounted for 79% of the individuals whereas other patterns were found in only 2-7% of the 57 analyzed mussels. Base mutations were observed at specific locations, mainly within COOH-terminus and 3'UTR, leading to 36 nucleotide sequence variants and 21 different coding …
Ceftaroline modulates the innate immune and host defense responses of immunocompetent cells exposed to cigarette smoke.
2017
Abstract Background Cigarette smoke, the principal risk factor for chronic obstructive pulmonary disease (COPD), negatively influences the effectiveness of the immune system’s response to a pathogen. The antibiotic ceftaroline exerts immune-modulatory effects in bronchial epithelial cells exposed to cigarette smoke. Aims and methods The present study aims to assess the effects of ceftaroline on TLR2 and TLR4 expression, LPS binding and TNF-α and human beta defensin (HBD2) release in an undifferentiated and PMA-differentiated human monocyte cell line (THP-1) exposed or not to cigarette smoke extracts (CSE). TLR2, TLR4, and LPS binding were assessed by flow cytometry, TNF-α and HBD2 release w…