Search results for "pathogenic"
showing 10 items of 203 documents
Risque phytosanitaire (ARP) portant sur Fusarium oxysporum f. sp. cubense (agent pathogène responsable de la maladie de Panama) pour les départements…
2018
Risque phytosanitaire (ARP) portant sur [i]Fusarium oxysporum[/i] f. sp.[u] cubense[/u] (agent pathogène responsable de la maladie de Panama) pour les départements d'Outre-mer
Selective Antimicrobial Effects of Curcumin@Halloysite Nanoformulation: A Caenorhabditis elegans Study
2019
Alterations in the normal gastrointestinal microbial community caused by unhealthy diet, environmental factors, and antibiotic overuse may severely affect human health and well-being. Novel antimicrobial drug formulations targeting pathogenic microflora while not affecting or even supporting symbiotic microflora are urgently needed. Here we report fabrication of a novel antimicrobial nanocontainer based on halloysite nanotubes loaded with curcumin and protected with a dextrin outer layer (HNTs+Curc/DX) and its effective use to suppress the overgrowth of pathogenic bacteria in Caenorhabditis elegans nematodes. Nanocontainers have been obtained using vacuum-facilitated loading of hydrophobic …
Identification of Novel Hexapeptides Bioactive against Phytopathogenic Fungi through Screening of a Synthetic Peptide Combinatorial Library
2002
The purpose of the present study was to improve the antifungal activity against selected phytopathogenic fungi of the previously identified hexapeptide PAF19. We describe some properties of a set of novel synthetic hexapeptides whose D-amino acid sequences were obtained through screening of a synthetic peptide combinatorial library in a positional scanning format. As a result of the screening, 12 putative bioactive peptides were identified, synthesized, and assayed. The peptides PAF26 (Ac-rkkwfw-NH(2)), PAF32 (Ac-rkwhfw-NH(2)), and PAF34 (Ac-rkwlfw-NH(2)) showed stronger activity than PAF19 against isolates of Penicillium digitatum, Penicillium italicum, and Botrytis cinerea. PAF26 and PAF3…
Type-IIA secreted phospholipase A2 is an endogenous antibiotic-like protein of the host.
2010
International audience; Type-IIA secreted phospholipase A(2) (sPLA(2)-IIA) has been proposed to play a role in the development of inflammatory diseases. It has been shown to release arachidonic acid, the precursor of proinflammatory eicosanoids, to hydrolyze phospholipids of pulmonary surfactant, and to bind to specific receptors located on cell surface membranes. However, the most established biological role of sPLA(2)-IIA is related to its potent bactericidal property in particular toward Gram-positive bacteria. This enzyme is present in animal and human biological fluids at concentrations sufficient to kill bacteria. Human recombinant sPLA(2)-IIA is able to kill Gram-positive bacteria at…
Top-down effects of a lytic bacteriophage and protozoa on bacteria in aqueous and biofilm phases
2014
Lytic bacteriophages and protozoan predators are the major causes of bacterial mortality in natural microbial communities, which also makes them potential candidates for biological control of bacterial pathogens. However, little is known about the relative impact of bacteriophages and protozoa on the dynamics of bacterial biomass in aqueous and biofilm phases. Here, we studied the temporal and spatial dynamics of bacterial biomass in a microcosm experiment where opportunistic pathogenic bacteria Serratia marcescens was exposed to particle‐feeding ciliates, surface‐feeding amoebas, and lytic bacteriophages for 8 weeks, ca. 1300 generations. We found that ciliates were the most efficient enem…
Strategies for Survival of Extracellular Pathogens
2002
Publisher Summary This chapter highlights a simple listing of microbial factors that may contribute to extracellular survival. In addition, it outlines principles and discusses prototypes for extracellular versus intracellular survival strategies. Strategies for extracellular survival can often be equated with pathogenicity mechanisms, and counteractive measures can therefore form the basis for prophylaxis or therapy of the respective infections. These aspects are aluded throughout the chapter, since they investigates how basic research into microbial virulence mechanisms can lead to advances in clinical medicine. Most bacteria that cause extracellular infections cannot afford to be engulfe…
Gangliosides and sialic acid effects upon newborn pathogenic bacteria adhesion: An in vitro study
2012
The effect of the main gangliosides (GM(1), GM(3), GD(3)) and free sialic acid (Neu5Ac) upon the adhesion of pathogenic bacteria implicated in infant diarrhoea is assessed in vitro using the Caco-2 cell line. Concentrations of the bioactive compounds found in the bioaccessible (soluble) fraction of infant formula and human milk are employed. Bacterial adhesion behaviour included enterotoxigenic Escherichia coli (ETEC), enteropathogenic E.coli (EPEC), Listeria monocytogenes, Salmonella entericaserovartyphi, Shigella sonnei, Campylobacter jejuni and Helicobacter pylori. Three different approaches were assayed: pre-incubation of bacteria and compounds before addition to cells (competition); pr…
Influence of Galvanic Microcells on Growth of Pathogenic Bacteria and Candida Yeast
2017
The aim of the study was to evaluate the influence of electrodes on growth of pathogenic bacteria and Candida albicans yeast. In the study, following references bacteria strains were used: Staphylococcus aureus ATTC 6538; Enterococcus faecalis ATTC 29212 (V); Enterococcus hirae ATTC 105441 (VI) and yeast strain Candida albicans ATTC 10231 (C40). Microelectrodes were prepared by ALCOR Center. Estimation of the biocidal effect of electrodes was carried out by medium poisoning method. The assessment of adhesion to the surface was performed by a modified Hawser’s method. Presence of adhesion was assessed by SEM analysis. The highest inhibition zones were obtained for Staphylococcus aureus ATTC …
An organogold compound as potential antimicrobial agent against drug resistant bacteria: Initial mechanistic insights
2021
Abstract The rise of antimicrobial resistance has necessitated novel strategies to efficiently combat pathogenic bacteria. Metal‐based compounds have been proven as a possible alternative to classical organic drugs. Here, we have assessed the antibacterial activity of seven gold complexes of different families. One compound, a cyclometalated Au(III) C^N complex, showed activity against Gram‐positive bacteria, including multi‐drug resistant clinical strains. The mechanism of action of this compound was studied in Bacillus subtilis. Overall, the studies point towards a complex mode of antibacterial action, which does not include induction of oxidative stress or cell membrane damage. A number …
Cellular interactions ofCandida albicanswith human oral epithelial cells and enterocytes
2010
The human pathogenic fungus Candida albicans can cause systemic infections by invading epithelial barriers to gain access to the bloodstream. One of the main reservoirs of C. albicans is the gastrointestinal tract and systemic infections predominantly originate from this niche. In this study, we used scanning electron and fluorescence microscopy, adhesion, invasion and damage assays, fungal mutants and a set of fungal and host cell inhibitors to investigate the interactions of C. albicans with oral epithelial cells and enterocytes. Our data demonstrate that adhesion, invasion and damage by C. albicans depend not only on fungal morphology and activity, but also on the epithelial cell type an…