Iskanje po repozitoriju

A+ | A- | | SLO | ENG

Povzetek: The emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants poses a challenge to current therapies and emphasises the need for targets that are less susceptible to mutation. The SARS-CoV-2 envelope protein (Epro) is a highly conserved viroporin and is of central importance to the viral life cycle, yet it remains underexplored as a therapeutic target. In this study, we have identified and characterised a novel lead candidate (LC) − (S)-N-(2-((1S,3S,5S,7S)-adamantan-2-yl)ethyl)-2-(butylamino)-3-(1H-indol-3-yl)propanamide − for inhibition of the SARS-CoV-2 Epro ion channel using combined in silico and in vitro approaches. Molecular dynamics (MD) simulations showed that LC forms stable complexes at the N-terminal vestibule, with key interactions at GLU8, THR9, THR11, ASN15, and LEU18, and a calculated binding affinity higher than that of the reference compound rimantadine within the applied MD/molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) framework. Results of in vitro experiments indicated that LC inhibits the model coronavirus murine hepatitis virus at late stages of the viral cycle. Activity under co-treatment conditions further suggests a direct virucidal effect or interference with early entry stages; an EC50 of approximately 12 μM was within the same micromolar range as those observed for the reference Epro inhibitors 5-(N,N-hexamethylene)amiloride and rimantadine. Quantitative PCR experiments showed delayed RNA replication in LC-treated infected cells, while light and transmission electron microscopy displayed the reduced release of virions and prevention of cell lysis. These results emphasise the central role of the Epro ion channel in the coronavirus life cycle and present LC as a promising candidate for the further development of novel coronavirus inhibitors.
Ključne besede: SARS-CoV-2 envelope protein, viroporin, ion channel blockers, molecular docking, molecular dynamics simulations, drug discovery, murine hepatitis virus, in vitro
Objavljeno v DiRROS: 11.06.2026; Ogledov: 17; Prenosov: 10
Celotno besedilo (9,89 MB)
Gradivo ima več datotek! Več...

Povzetek: Monitoring airborne inoculum of pathogens is important for plant disease surveillance. Here, we evaluate spider webs as passive environmental DNA (eDNA) samplers for detecting the pathogenic fungus Hymenoscyphus fraxineus, the causal agent of ash dieback, in a forest environment. In a temperate mixed forest, we compared two types of spider webs (orb and sheet webs) with a conventional passive sampler (filter paper) over matched day (orb) and week (sheet) deployments. Laboratory validation confirmed that webs exposed to airborne spores from apothecia yield positive qPCR signals. Across seven field sampling campaigns, both a species-specific qPCR (Hfrax) and a broad fungal assay (FQ) detected fungal eDNA on spider webs more reliably and at higher relative quantities than on filter paper. In daily and weekly pairs, orb and sheet web vs. filters, the median ΔCq (filter − web) was above 4 for both qPCR assays (Wilcoxon paired, p < 0.05), which corresponds to more than a 10-fold difference in the amount of target DNA. This study provides proof of concept for using spider webs as scalable, low-cost tools suitable for targeted (qPCR) surveillance to complement aerobiological networks.
Ključne besede: airborne eDNA, ash dieback, forest pathogens, Hymenoscyphus fraxineus, passive sampling, qPCR, spider webs, forest health
Objavljeno v DiRROS: 03.06.2026; Ogledov: 121; Prenosov: 73
Celotno besedilo (626,95 KB)
Gradivo ima več datotek! Več...

Povzetek: Phyllosticta citricarpa is the causal agent of citrus black spot (CBS), a disease affecting most citrus species and cultivars, particularly lemons (Citrus limon) and sweet oranges (C. sinensis). The pathogen causes fruit blemishes and premature fruit drop, leading to substantial yield and quality losses. Phyllosticta citricarpa is of global economic importance and is regulated by several citrus-growing countries, including those in the European Union (EU). The aim of this study was to develop a novel approach for early detection of P. citricarpa in environmental samples and to assess the status of P. citricarpa in selected citrus-growing areas of the EU where this species had previously been reported from leaf litter. Between 2018 and 2021, citrus plant material, air and rainwater samples were collected and analysed for the presence of Phyllosticta spp. in orchards in Greece, Italy, and Malta. Molecular analyses using qPCR assays targeting P. citricarpa were employed for the analysis of air and rainwater samples. The performance of the testing protocol was evaluated prior to sample analysis, and 1,000 conidia were determined to be the minimum number of spores required for reliable detection. No CBS symptoms were observed, and no evidence of P. citricarpa was found in collected citrus plant material, air, or rainwater samples. The only Phyllosticta species detected during this study was the endophyte P. capitalensis, isolated from citrus leaf litter in Greece. These findings support the results of official EU surveys, which indicate the current absence of P. citricarpa in the surveyed areas and demonstrate the value of integrating environmental monitoring with molecular diagnostics for plant health surveillance. The methodologies developed here offer a robust framework for early warning and rapid response, supporting efforts to prevent CBS outbreaks in Europe and can be adapted for other fungal pathogens.
Ključne besede: citrus black spot, early detection, molecular diagnostics, Phyllosticta citricarpa, spore trapping
Objavljeno v DiRROS: 30.03.2026; Ogledov: 262; Prenosov: 250
Raziskovalni podatki (95,54 KB)
Gradivo ima več datotek! Več...

Povzetek: The SARS-CoV-2 envelope protein (2-EPRO), a viroporin crucial for viral pathogenesis, is a promising target for antiviral drug development as it is highly conserved and functionally important. Although it is a promising therapeutic target for the treatment of COVID-19, it has often been overlooked in previous studies. In this study, a high-throughput virtual screening of nearly one billion compounds was performed, followed by rigorous filtering and re-docking. Eight best-scoring and chemically versatile lead candidates were identified. In molecular dynamics simulations, three of these ligands showed stable protein-ligand complexes occupying the 2-EPRO channel pore. Among these, ZINC001799167680 (L3) and ZINC001081252239 (L2) exhibited the strongest binding a˙inity, with key interactions at residues ASN15, THR11 and GLU8 identified by Molecular Mechanics Poisson-Boltzmann Surface Area analysis. All ligands were compared with the known inhibitor rimantadine and showed stronger binding to the protein. These in silico results highlight the potential of focusing on the 2-EPRO ion channel in the development of novel COVID-19 therapeutics and pave the way for further in vitro and in vivo studies.
Ključne besede: SARS-CoV-2 envelope protein, viroporin, ion channel, channel blockers, molecular dynamics simulations, free energy calculations, drug discovery
Objavljeno v DiRROS: 05.09.2025; Ogledov: 731; Prenosov: 421
Celotno besedilo (1,82 MB)
Gradivo ima več datotek! Več...

Povzetek: To investigate the dynamics of the potato – Potato virus Y (PVY) compatible interaction in relation to salicylic acid - controlled pathways we performed experiments using non-transgenic potato cv. Désirée, transgenic NahG-Désirée, cv. Igor and PVYNTN, the most aggressive strain of PVY. The importance of salicylic acid in viral multiplication and symptom development was confirmed by pronounced symptom development in NahG-Désirée, depleted in salicylic acid, and reversion of the effect after spraying with 2,6-dichloroisonicotinic acid (a salicylic acid - analogue). We have employed quantitative PCR for monitoring virus multiplication, as well as plant responses through expression of selected marker genes of photosynthetic activity, carbohydrate metabolism and the defence response. Viral multiplication was the slowest in inoculated potato of cv. Désirée, the only asymptomatic genotype in the study. The intensity of defence-related gene expression was much stronger in both sensitive genotypes (NahG-Désirée and cv. Igor) at the site of inoculation than in asymptomatic plants (cv. Désirée). Photosynthesis and carbohydrate metabolism gene expression differed between the symptomatic and asymptomatic phenotypes. The differential gene expression pattern of the two sensitive genotypes indicates that the outcome of the interaction does not rely simply on one regulatory component, but similar phenotypical features can result from distinct responses at the molecular level.
Ključne besede: plant viruses, plant diseases
Objavljeno v DiRROS: 04.03.2025; Ogledov: 953; Prenosov: 608
Celotno besedilo (632,53 KB)
Gradivo ima več datotek! Več...