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Fig mosaic disease (FMD) poses a significant threat to fig (Ficus carica) trees globally. Fig mosaic virus (Emaravirus fici, Family Fimoviridae) is one of the main causes involved in FMD. E. fici has been reported in many countries, including Iran. This research investigated the genetic diversity and distribution of this virus in Kermanshah Province, the third fig‐producing region in Iran. In 2021 and 2022, 128 samples, mainly displaying FMD symptoms, were collected from fig trees across nine counties. Using DAS‐ELISA with polyclonal antibodies, 86 samples tested positive for fig mosaic virus. The 2‐year‐old healthy fig saplings grafted with scions from infected trees exhibited mosaic symptoms and tested positive for the virus in DAS‐ELISA. Reverse transcription‐polymerase chain reaction (RT‐PCR) by RdRp‐specific primers (E5‐s and E5‐a) also amplified a DNA fragment with the expected size of about 302 bp from the ELISA‐positive samples. Five of the 12 symptomless samples showed positive results in both DAS‐ELISA and RT‐PCR. This indicates that the absence of symptoms in propagation sources does not imply that they are virus‐free. Nucleotide sequences of RT‐PCR products confirmed the fig mosaic virus infection. BLAST analysis of 20 samples (GenBank accession numbers OQ552535 to OQ552554) revealed that 19 sequences show high nucleotide identity (93.4%–96.8%) with an isolate from Lorestan Province, Iran (GenBank accession number KT732024). Notably, isolate FM203 showed distinct genetic divergence (86.6%–90.2% nucleotide identity) and shared similarities with some other Iranian isolates, including those from Kermanshah and Mazandaran provinces. Phylogenetic analysis grouped most isolates with the Lorestan isolate, while FM203 was placed in a separate cluster. This study highlighted the widespread presence of fig mosaic virus in Kermanshah Province, emphasizing varying infection rates across different counties, with Dalahoo County (Rijab) showing the highest prevalence. [ABSTRACT FROM AUTHOR]

This work presents a new electrochemical immunosensor for sensitive and rapid detection of infectious bursal disease virus (IBDV) based on the combination of a modified glassy carbon (GC) electrode and fast Fourier transforms square wave voltammetry. The immunosensorwasa GC modified electrodeposited gold NPs, self-assembled monolayer and immobilised anti-IBDV antibodies. The interaction between the antibody and antigen was followed by measuring the change in the redox currents of the probe, using fast Fourier transform square wave voltammetry technique. The obtained linear range was 40–2500 particle mL−1 with the detection limit of 14 particle mL−1. This immunosensor was successfully applied to determine IBDV in real samples. The prepared immunosensor is selective and displayed excellent stable sensitivity over a long period of the observed time. [ABSTRACT FROM AUTHOR]

Preservation of elite key lime (Citrus aurantifolia) genotypes using efficient micropropagation and regeneration protocols is very important for new breeding programmes. The objective of the present study was to develop an efficient protocol for micropropagation and maintenance of elite genotypes of key lime based on slow growth and starvation strategy. To do this, regenerated shoots were starved, and the growth was compromised via avoiding subcultures for 4, 8, 12 and 24 months. The numbers of responsive explants and adventitious shoots per each explant were evaluated in the presence of benzylaminopurine (BAP). The results showed that the 12- and 24-month starved explants treated with 1 mg/l BAP were able to produce four times more shoots than the control. In addition, the influences of horizontal or vertical layering explants over medium were evaluated. The results indicated that all horizontally layered explants significantly produced 25% adventitious shoots more than vertical explants, most likely owing to more contact with the surface medium. Finally, it could be concluded that application of slow growth, starvation strategy and also horizontally layering of the explants could efficiently enhance micropropagation and maintenance of threatened elite key lime genotypes with a low cost. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor alpha (TNF-α) expression amplifies to excess amounts in several disorders such as rheumatoid arthritis and psoriasis. Although, Anti-TNF biologics have revolutionized the treatment of these autoimmune diseases, formation of anti-drug antibodies (ADA) has dramatically affected their use. The next generation antibodies (e.g. Fab, scFv) have not only reduced resulted immunogenicity, but also proved several benefits including better tumor penetration and more rapid blood clearance. Using affinity selection procedures in this study, a scFv antibody clone was isolated from naïve Tomlinson I phage display library that specifically recognizes and binds to TNF-α. The TNF-α recombinant protein was expressed in genetically engineered Escherichia coli SHuffle® T7 Express, for the first time, which is able to express disulfide-bonded recombinant proteins into their correctly folded states. ELISA-based affinity characterization results indicated that the isolated novel 29.2 kDa scFv binds TNF-α with suitable affinity. In-silico homology modeling study using 'ModWeb' as well as molecular docking study using Hex program confirmed the scFv and TNF-α interactions with a scFv-TNF- α binding energy of around -593 kj/mol which is well in agreement with our ELSIA results. The cloned scFv antibody may be potentially useful for research and therapeutic applications in the future. [ABSTRACT FROM AUTHOR]

Purpose: To develop specific single chain variable fragments (scFv) against infectious bursal disease virus (IBDV) via phage display technology. Methods: Purified viruses were initially applied for iterative panning rounds of scFv phage display libraries. The binding ability of the selected scFv antibody fragments against the IBDV particles was analyzed by indirect enzyme-linked immunosorbent assay (ELISA) followed by blotting assays. Threedimensional (3D) structure of the selected scFv antibody fragment and VP3 protein were predicted through in silico analysis. Structural characterization of the antibody-antigen complexes was carried out by computational docking analysis. Results: The serological results obtained from the ELISA and blotting analysis showed that the selected clones produced specific scFv antibody fragments that were capable of effectively detecting infectious bursal disease (IBD) in the infected animal tissue. Biodiversity analysis by BstNI finger printing and nucleotide sequencing revealed that there was no major difference in nucleotide sequences of the selected clones. Further analysis demonstrated that this recombinant fragment of the antibody was able to bind to VP3 structural protein of IBDV with a molecular weight of ~30 kDa. Molecular docking results revealed that the binding energy of scFv to IBDV-VP3 was 545 kj/mol. Conclusion: The developed scFv antibody fragments possess great potentials for the diagnosis of IBD. The findings of the present study confirm the feasibility of using phage display technology for rapid production of antibodies against IBD diseases by applying naïve scFv libraries. [ABSTRACT FROM AUTHOR]

Rhizomania is the most destructive disease in sugar beet throughout the world. The disease is caused by Beet necrotic yellow vein virus (BNYVV). Polymyxa betae (Keskin) is the only known vector of BNYVV, for transmission of the virus between the plants. Developing molecular diagnostic methods has a major impact on forecasting and epidemiological studies as well as screening sugar beet plants used in resistance breeding programmes. In the present study, quantum dots (QDs) were biofunctionalized with a specific antibody against P. betae. The glutathione-S-transferase protein's (GST) corresponding antibody (anti-GST) was effectively conjugated to Tioglicolicacid-modified Cadmium-Telluride QDs (CdTe-QDs) synthesized in an aqueous solution via electrostatic interaction. The dye (Rhodamine) molecules were attached to the GST. Donor–acceptor complexes (QDs-Ab-GST-Rhodamine) were then formed based on the antigen–antibody interaction. The mutual affinity of the antigen and the antibody brought the CdTeQDs and rhodamine together close enough to allow the resonance dipole–dipole coupling required for fluorescence resonance energy transfer (FRET) to occur. The immunosensor constructed showed a high sensitivity and specificity of 100%, acceptable stability and could be used for real sample detection with consistent results. To the best of our knowledge, this is the first report on designing a nano-based biosensing tool for the detection of plant pathogenic fungi. [ABSTRACT FROM PUBLISHER]

The plasmodiophoromycete Polymyxa betae and P. graminis are eukaryotic biotrophic parasites residing in the roots of chenopodiacae and gramineae plants. They are natural transmitting agents of several important plant viruses such as are beet necrotic yellow vein virus (BNYW), beet soil borne mosaic virus (BSBMV), wheat soil-borne mosaic virus (WSBMV). Developing advanced high-throughput diagnostic methods capable of accurate detection of these pathogens could assist with the screening programs and consequently with the development of disease-resistant germplasms. In the present study, a previously developed quantum dots (QDs) FRET-based nano-biosensor was upgraded to a high-throughput version. QDs were functionalized with a specific antibody against the P. betae's specific glutathione-S-transferase (GST) protein. On the other hand, GST was conjugated to Rhodamine dye. Ninety six-well polystyrene plates were used as the detection platform. The mutual affinity of the antigen and the antibody brought the CdTe QDs and rhodamine together close enough to allow the resonance dipole-dipole coupling required for fluorescence resonance energy transfer (FRET) to occur. The immunosensor constructed showed a high sensitivity and specificity of 100%, and was successfully used for high-throughput screening of 96 real samples with consistent results within the course of less than 30 minutes.