BIOFILM GENES PRESENCE, BIOFILM ANALYSIS AND ANTIMICROBIAL PEPTIDES ACTIVITY AGAINST STAPHYLOCOCCUS AUREUS OF ANIMAL ORIGIN

Fragments of β-thymosin from the sea urchin Paracentrotus lividus as potential antimicrobial peptides against staphylococcal biofilms.

The immune mediators in echinoderms can be a potential source of novel antimicrobial peptides (AMPs) applied toward controlling pathogenic staphylococcal biofilms that are intrinsically resistant to conventional antibiotics. The peptide fraction5 kDa from the cytosol of coelomocytes 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 was active against all planktonic-tested strains but also showed antibiofilm properties against staphylococcal strains. Additionally, we demonstrated the presence of three small peptides in the 5-CC belonging to segment 9-41 of a P. lividusβ-thymosin. The…

Characterization of haemolytic activity of coelomocytes of Holothuria tubulosa

Phylogenetic analysis recognizes echinoderms as a key group of deuterostomes, therefore the species in this group are useful for the study of the evolution of innate immunity responses. In addition, this marine invertebrate lives in coastal and estuarine waters that are directly exposed to potentially pathogenic microorganisms and stressful anthropogenic factors. Coelomocyte populations seem to be essential to immune-defence functions such as phagocytosis, ROI production, cytotoxicity, synthesis and release of antimicrobial substances including lectin, cytokine, C3-like expression, prophenoloxidase activity and capsule formation. Holothurians’ coelomocyte populations contain several coelomo…

Cytology, Histology and Histochemistry

Separated hemocyte populations from the ascidian Ciona intestinalis contain and release in vitro opsonizingCa++-independent and β-galactoside specific lectins

Effects of diclofenac on the gametes and embryonic development of Arbacia lixula

Diclofenac (DCF), a non-steroidal anti-inflammatory drug (NSAID), is among the main pollutants of aquatic environments. Nevertheless, even if several authors evaluated its effects on marine organisms, no work has ever analysed its impact on the sea urchin Arbacia lixula. The purpose of this study was to analyse, for the first time, the impact of DCF at different concentrations (50 mg/l, 5 mg/l, 0.5 mg/l, 0.05 mg/l) on A. lixula embryos and gametes to indicate possible safe minimum levels of release of this drug in marine environments. Our results showed significant concentration-dependent effects on embryonic development (decrease in the number of developed embryos and increase in the quant…

Effects of Steinernema carpocapsae (Nematoda: Steinernematidae) on biological parameters of larvae responses of Rhynchophorus ferrugineus (Coleoptera: Curculionidae)

Rhynchophorus ferrugineus (Coleoptera: Curculionidae) known as the Red Palm Weevil (RPW) is becoming more and more of a problem in Italy, and especially in Sicily, where it is well adapted. The infestations are mainly in the urban areas, and for that reason, chemical control is not advisable. Data from literature show that entomopathogenic nematodes (EPN) particularly Steirnenema carpocapsae, have a quite successfully control of RPW. However, results coming from the laboratories are often in contrast with each other and no data are available on precise doses and S. carpocapsae seems not be able to reproduce itself in the host. The effect of EPN on the RPW immune system is totally unknown. D…

Are there autochthonous Ferrissia (Mollusca: Planorbidae) in the Palaearctic? Molecular evidence of a widespread North American invasion of the Old World

In the last few decades, findings of freshwater limpets belonging to the genus Ferrissia have been frequent and widely distributed throughout the Palaearctic and beyond. The widespread presence of a Nearctic alien taxon was proved, but no consensus was achieved about the possible existence of autochthonous Ferrissia taxa in the area, an occurrence which would be supported by the presence of gastropod fossils attributed to the genus throughout Eurasia and North Africa. In order to test the hypothesis of a possible persistence of autochthonous Ferrissia taxa in the Palaearctic to the present day, all the published data on the genetic diversity of Ferrissia populations occurring in the area we…