• MeSH
• Ascophyllum chemie   imunologie   MeSH
• betain * chemie   MeSH
• hlístice chemie   patogenita   růst a vývoj   MeSH
• hmyz chemie   patogenita   růst a vývoj   MeSH
• houby chemie   patogenita   růst a vývoj   MeSH
• imunita rostlin * imunologie   účinky léků   MeSH
• interakce hostitele a patogenu * imunologie   účinky léků   MeSH
• paraziti chemie   růst a vývoj   účinky léků   MeSH
• rostlinné extrakty MeSH
• rostliny MeSH
• sloučeniny draslíku MeSH
• statistika jako téma MeSH
• Tylenchoidea růst a vývoj   účinky léků   MeSH

Antimicrobial peptides are ubiquitous components of eukaryotic innate immunity. Defensins are a well-known family of antimicrobial peptides, widely distributed in ticks, insects, plants and mammals, showing activity against bacteria, viruses, fungi, yeast and protozoan parasites. Ixodes ricinus is the most common tick species in Europe and is a vector of pathogens affecting human and animal health. Recently, six defensins (including two isoforms) were identified in I. ricinus. We investigated the evolution of the antimicrobial activity of I. ricinus defensins. Among the five unique defensins, only DefMT3, DefMT5 and DefMT6 showed in vitro antimicrobial activity. Each defensin was active against rather distantly-related bacteria (P < 0.05), significantly among Gram-negative species (P < 0.0001). These three defensins represent different clades within the family of tick defensins, suggesting that the last common ancestor of tick defensins may have had comparable antimicrobial activity. Differences in electrostatic potential, and amino acid substitutions in the β-hairpin and the loop bridging the α-helix and β-sheet may affect the antimicrobial activity in DefMT2 and DefMT7, which needs to be addressed. Additionally, the antimicrobial activity of the γ-core motif of selected defensins (DefMT3, DefMT6, and DefMT7) was also tested. Interestingly, compared to full length peptides, the γ-core motifs of these defensins were effective against less species of bacteria. However, the antifungal activity of the γ-core was higher than full peptides. Our results broaden the scope of research in the field of antimicrobial peptides highlighting the overlooked ability of arthropod defensins to act against distantly-related microorganisms.

• MeSH
• aminokyselinové motivy MeSH
• bakteriální infekce imunologie   MeSH
• biologická evoluce MeSH
• defensiny genetika   metabolismus   MeSH
• druhová specificita MeSH
• hmyzí proteiny genetika   metabolismus   MeSH
• interakce hostitele a patogenu MeSH
• klíště * MeSH
• kultivované buňky MeSH
• mykózy imunologie   MeSH
• přirozená imunita MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• Publikační typ
• abstrakt z konference MeSH

INTRODUCTION: Red blood cells (RBCs), also known as erythrocytes, are underestimated in their role in the immune system. In mammals, erythrocytes undergo maturation that involves the loss of nuclei, resulting in limited transcription and protein synthesis capabilities. However, the nucleated nature of non-mammalian RBCs is challenging this conventional understanding of RBCs. Notably, in bony fishes, research indicates that RBCs are not only susceptible to pathogen attacks but express immune receptors and effector molecules. However, given the abundance of RBCs and their interaction with every physiological system, we postulate that they act in surveillance as sentinels, rapid responders, and messengers. METHODS: We performed a series of in vitro experiments with Cyprinus carpio RBCs exposed to Aeromonas hydrophila, as well as in vivo laboratory infections using different concentrations of bacteria. RESULTS: qPCR revealed that RBCs express genes of several inflammatory cytokines. Using cyprinid-specific antibodies, we confirmed that RBCs secreted tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ). In contrast to these indirect immune mechanisms, we observed that RBCs produce reactive oxygen species and, through transmission electron and confocal microscopy, that RBCs can engulf particles. Finally, RBCs expressed and upregulated several putative toll-like receptors, including tlr4 and tlr9, in response to A. hydrophila infection in vivo. DISCUSSION: Overall, the RBC repertoire of pattern recognition receptors, their secretion of effector molecules, and their swift response make them immune sentinels capable of rapidly detecting and signaling the presence of foreign pathogens. By studying the interaction between a bacterium and erythrocytes, we provide novel insights into how the latter may contribute to overall innate and adaptive immune responses of teleost fishes.

• MeSH
• Aeromonas hydrophila * imunologie   MeSH
• cytokiny * metabolismus   imunologie   MeSH
• erytrocyty * imunologie   metabolismus   MeSH
• fagocytóza imunologie   MeSH
• gramnegativní bakteriální infekce * imunologie   MeSH
• kapři * imunologie   mikrobiologie   MeSH
• nemoci ryb * imunologie   mikrobiologie   MeSH
• PAMP struktury imunologie   MeSH
• přirozená imunita MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• betain aplikace a dávkování   terapeutické užití   MeSH
• nemoci rostlin mikrobiologie   parazitologie   účinky léků   MeSH
• Phaeophyceae chemie   MeSH

Legumes are ubiquitous, low-cost meals that are abundant in protein, vitamins, minerals, and calories. Several biotic constraints are to blame for the global output of legumes not meeting expectations. Fungi, in particular, are substantial restrictions that not only hinder production but also pose a serious health risk to both human and livestock consumption. Athelia rolfsii (Syn. Sclerotium rolfsii) is a dangerous pathogenic fungus that attacks most crops, causing massive yield losses. Legumes are no longer immune to this dreadful fungus, which can potentially result in a 100% yield loss. The initial disease symptoms based on the formation of brown color lesions at the point of infection and further development of mycelia, followed by yellowing and wilting of the whole plant. To tackle such situation, various strategies, i.e., management in cultural practices, disease-free plant growth, genetic changes, crop hybridization and in vitro culture techniques have been undertaken. This present review encapsulates the entire situation, from sclerotial dissemination through infection development and control in legume crops, with the goal of developing a tangible understanding of sustainable legume production improvements. Further study in this area might be led in an integrated manner as a result of this information, which could contribute to a better understanding of the processes of disease incidence, resistance mechanism, and its control, and fostering greater inventiveness in the production of legumes.

• MeSH
• Ascomycota * MeSH
• Basidiomycota * genetika   MeSH
• Fabaceae * MeSH
• lidé MeSH
• půda MeSH
• zelenina MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: White-nose syndrome is a disease of hibernating insectivorous bats associated with the fungus Geomyces destructans. It first appeared in North America in 2006, where over a million bats died since then. In Europe, G. destructans was first identified in France in 2009. Its distribution, infection dynamics, and effects on hibernating bats in Europe are largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: We screened hibernacula in the Czech Republic and Slovakia for the presence of the fungus during the winter seasons of 2008/2009 and 2009/2010. In winter 2009/2010, we found infected bats in 76 out of 98 surveyed sites, in which the majority had been previously negative. A photographic record of over 6000 hibernating bats, taken since 1994, revealed bats with fungal growths since 1995; however, the incidence of such bats increased in Myotis myotis from 2% in 2007 to 14% by 2010. Microscopic, cultivation and molecular genetic evaluations confirmed the identity of the recently sampled fungus as G. destructans, and demonstrated its continuous distribution in the studied area. At the end of the hibernation season we recorded pathologic changes in the skin of the affected bats, from which the fungus was isolated. We registered no mass mortality caused by the fungus, and the recorded population decline in the last two years of the most affected species, M. myotis, is within the population trend prediction interval. CONCLUSIONS/SIGNIFICANCE: G. destructans was found to be widespread in the Czech Republic and Slovakia, with an epizootic incidence in bats during the most recent years. Further development of the situation urgently requires a detailed pan-European monitoring scheme.

• MeSH
• Ascomycota klasifikace   genetika   fyziologie   MeSH
• Chiroptera klasifikace   mikrobiologie   MeSH
• dermatomykózy epidemiologie   mikrobiologie   MeSH
• DNA fungální chemie   genetika   MeSH
• druhová specificita MeSH
• hibernace MeSH
• incidence MeSH
• interakce hostitele a patogenu MeSH
• molekulární sekvence - údaje MeSH
• ribozomální DNA chemie   genetika   MeSH
• roční období MeSH
• sekvenční analýza DNA MeSH
• zeměpis MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Slovenská republika MeSH

The universal protease inhibitors of the alpha(2)-macroglobulin (alpha(2)M) family are evolutionarily conserved constituents of innate immunity, presumably because they guard organisms against undesired proteolytic attacks of a different origin. Here, we determined the primary structure of alpha(2)-macroglobulin from the hard tick Ixodes ricinus (IrAM) by sequencing of overlapping PCR products. Predicted disulfide and glycosylation patterns, post-translational cleavage and alternative splicing within its 'bait region' demonstrate that IrAM is closely related to the alpha(2)-macroglobulin from the soft tick Ornithodoros moubata. The IrAM message is expressed in all tick developmental stages and tissues, except for the gut, and the protein was detected to be mainly present in the hemolymph. Silencing of IrAM by dsRNA interference markedly reduced the phagocytosis of a potential pathogen, Chryseobacterium indologenes, by tick hemocytes both in vitro and in vivo. In contrast, phagocytosis of the Lyme disease spirochete Borrelia burgdorferi or a commensal bacteria Staphylococcus xylosus was not affected by the IrAM knock-down. Similar results were obtained upon deactivation of all thioester proteins in tick hemolymph by methylamine. We have further demonstrated that phagocytosis of C. indologenes is dependent on an active metalloprotease secreted by the bacteria. These data indicate that interaction of tick alpha(2)-macroglobulin with a protease of an invading pathogen is linked with cellular immune response.

• MeSH
• alfa-makroglobuliny farmakologie   genetika   chemie   imunologie   MeSH
• Chryseobacterium imunologie   MeSH
• fagocytóza imunologie   MeSH
• fenantroliny farmakologie   MeSH
• financování organizované MeSH
• hemocyty imunologie   mikrobiologie   účinky léků   MeSH
• hemolymfa imunologie   MeSH
• klíště genetika   imunologie   mikrobiologie   MeSH
• metaloproteasy metabolismus   účinky léků   MeSH
• methylaminy farmakologie   MeSH
• molekulární sekvence - údaje MeSH
• RNA interference MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

Banana Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is soil-borne disease of banana (Musa spp.) causing significant economic losses. Extensins and arabinogalactan proteins (AGPs) are cell wall components important for pathogen defence. Their significance for Foc resistance in banana was not reported so far. In this study, two banana cultivars differing in Foc sensitivity were used to monitor the changes in transcript levels, abundance and distribution of extensins and AGPs after wounding and Foc inoculation. Extensins mainly appeared in the root cap and meristematic cells. AGPs recognized by JIM13, JIM8, PN16.4B4 and CCRC-M134 antibodies located in root hairs, xylem and root cap. Individual AGPs and extensins showed specific radial distribution in banana roots. At the transcript level, seven extensins and 23 AGPs were differentially expressed between two banana cultivars before and after treatments. Two extensins and five AGPs responded to the treatments at the protein level. Most extensins and AGPs were up-regulated by wounding and pathogen inoculation of intact plants but down-regulated by pathogen attack of wounded plants. Main components responsible for the resistance of banana were MaELP-2 and MaPELP-2. Our data revealed that AGPs and extensins represent dynamic cell wall components involved in wounding and Foc resistance.

• MeSH
• banánovník mikrobiologie   fyziologie   MeSH
• epitopy imunologie   MeSH
• Fusarium * MeSH
• glykoproteiny genetika   metabolismus   MeSH
• interakce hostitele a patogenu genetika   MeSH
• kořeny rostlin genetika   metabolismus   mikrobiologie   MeSH
• mukoproteiny genetika   metabolismus   MeSH
• nemoci rostlin genetika   mikrobiologie   MeSH
• odolnost vůči nemocem genetika   MeSH
• regulace genové exprese u rostlin * MeSH
• rostlinné proteiny genetika   imunologie   metabolismus   MeSH
• transport proteinů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Eukaryotes commonly host communities of heritable symbiotic bacteria, many of which are not essential for their hosts' survival and reproduction. There is laboratory evidence that these facultative symbionts can provide useful adaptations, such as increased resistance to natural enemies. However, we do not know how symbionts affect host fitness when the latter are subject to attack by a natural suite of parasites and pathogens. Here, we test whether two protective symbionts, Regiella insecticola and Hamiltonella defensa, increase the fitness of their host, the pea aphid (Acyrthosiphon pisum), under natural conditions. We placed experimental populations of two pea aphid lines, each with and without symbionts, in five wet meadow sites to expose them to a natural assembly of enemy species. The aphids were then retrieved and mortality from parasitoids, fungal pathogens and other causes assessed. We found that both Regiella and Hamiltonella reduce the proportion of aphids killed by the specific natural enemies against which they have been shown to protect in laboratory and cage experiments. However, this advantage was nullified (Hamiltonella) or reversed (Regiella) by an increase in mortality from other natural enemies and by the cost of carrying the symbiont. Symbionts therefore affect community structure by altering the relative success of different natural enemies. Our results show that protective symbionts are not necessarily advantageous to their hosts, and may even behave more like parasites than mutualists. Nevertheless, bacterial symbionts may play an important role in determining food web structure and dynamics.

• MeSH
• Enterobacteriaceae fyziologie   MeSH
• genetická zdatnost MeSH
• houby fyziologie   MeSH
• interakce hostitele a parazita MeSH
• interakce hostitele a patogenu * MeSH
• mšice genetika   mikrobiologie   parazitologie   fyziologie   MeSH
• sršňovití fyziologie   MeSH
• symbióza * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH