Virology

Porcine epidemic diarrhea virus (PEDV) causes severe diarrhea and death in piglets, resulting in significant economic losses for the pork industry. There is an urgent need for new treatment strategies. Here, we focused on optimizing the process of purifying natural hyperoside (nHYP) from hawthorn and evaluating its effectiveness against PEDV both in vitro and in vivo. Our findings demonstrated that nHYP with a purity >98% was successfully isolated from hawthorn with an extraction rate of 0.42 mg/g. Furthermore, nHYP exhibited strong inhibitory effects on PEDV replication in cells, with a selection index of 9...

Paramyxoviruses are reported to block apoptosis for their replication, but the mechanisms remain unclear. Furthermore, regulation of mitochondrial apoptosis by paramyxoviruses has been hardly reported. We investigated whether and how human parainfluenza virus type 2 (hPIV-2) counteracts apoptosis. Infection of recombinant hPIV-2 carrying mutated V protein showed higher caspase 3/7 activity and higher cytochrome c release from mitochondria than wild type hPIV-2 infection. This indicates that V protein controls mitochondrial apoptosis pathway...

This research focuses on analyzing the dynamics of neutralizing antibody (nAbs) titers against type 5 adenovirus (Ad5) in the adult population of Russia following vaccination against the novel coronavirus infection with recombinant adenovirus type-5 COVID-19 vaccine (CanSino Biologics, China). The impact of the Ad5 vector on nAb titers was investigated using 302 blood serum samples from individuals who received a single dose of the Ad5-nCoV vector vaccine. The research revealed that 33.8% of adults in Russia had pre-existing anti-Ad5 nAbs before the pandemic...

High variability and adaptability of RNA viruses allows them to spread between humans and animals, causing large-scale infectious diseases which seriously threat human and animal health and social development. At present, AIDS, viral hepatitis and other viral diseases with high incidence and low cure rate are still spreading around the world. The outbreaks of Ebola, Zika, dengue and in particular of the global pandemic of COVID-19 have presented serious challenges to the global public health system. The development of highly effective and broad-spectrum antiviral drugs is a substantial and urgent research subject to deal with the current RNA virus infection and the possible new viral infections in the future...

The SARS-CoV-2 Omicron variant, which was classified as a variant of concern (VOC) by the World Health Organization on 26 November 2021, has attracted worldwide attention for its high transmissibility and immune evasion ability. The existing COVID-19 vaccine has been shown to be less effective in preventing Omicron variant infection and symptomatic infection, which brings new challenges to vaccine development and application. Here, we evaluated the immunogenicity and safety of an Omicron variant COVID-19 inactivated vaccine containing aluminum and CpG adjuvants in a variety of animal models...

Many viruses employ a process known as superinfection exclusion (SIE) to block subsequent entry or replication of the same or closely related viruses in the cells they occupy. SIE is also referred to as Cross-protection refers to the situation where a host plant infected by a mild strain of a virus or viroid gains immunity against a more severe strain closely related to the initial infectant. The mechanisms underlying cross-protection are not fully understood. In this study, we performed a comparative transcriptomic analysis of potato (Solanum tuberosum L...

The human norovirus (HuNov) is the leading cause of acute gastroenteritis (AGE) worldwide. Mucosal secretory IgA (sIgA) in the gastrointestinal tract interrupts the interaction between host cells and HuNov, thus inhibiting viral infection. In this study, we constructed a recombinant Saccharomyces cerevisiae (S. cerevisiae) expressing the HuNov P protein (GII. 4) and evaluated its immunogenicity in mice after oral delivery. First, the recombinant S. cerevisiae (EBY100/pYD1-P) efficiently expressed P, as evidenced by western blotting and indirect fluorescent assay...

A begomovirus isolated from whiteflies (Bemisia tabaci) and tomato, sweet potato in China was found to be representative of a distinct begomovirus species, for which the name tomato yellow leaf curl Chuxiong virus (TYLCCxV) is proposed. The results of genomic identification and sequence comparison showed that TYLCCxV shares the highest complete nucleotide sequence identity (88.3%) with croton yellow vein mosaic virus (CroYVMV), and may have originated from the recombination between synedrella leaf curl virus (SyLCV) and squash leaf curl Yunnan virus (SLCuYV)...

The herpes simplex virus 1 DNA polymerase contains a highly conserved structural motif found in most family B polymerases and certain RNA-binding proteins. To investigate its importance within cells, we constructed a mutant virus with substitutions in two residues of the motif and a rescued derivative. The substitutions resulted in severe impairment of plaque formation, yields of infectious virus, and viral DNA synthesis while not meaningfully affecting expression of the mutant enzyme, its co-localization with the viral single-stranded DNA binding protein at intranuclear punctate sites in non-complementing cells or in replication compartments in complementing cells, or viral DNA polymerase activity...

Recent ICTV taxonomy updates significantly changed phage taxonomy, yet a thorough phage classification workflow doesn't exist. This study compares six categorization tools and establishes a novel multi-method approach, combining genome similarity and specialized protein analysis. Applying the method to APEC phage P151 showed consistent categorization across platforms. A possible workflow for phage classification is proposed; offering a versatile tool for phage research and development.

Our laboratory previously discovered a novel rhabdovirus in the Spodoptera frugiperda Sf9 insect cell line that was designated as Sf-rhabdovirus. Using limiting dilution, this cell line was found to be a mixed population of cells infected by Sf-rhabdovirus variants containing either the full length X accessory gene with a 3.7 kb internal duplication (designated as Sf-rhabdovirus X+3.7 ) or lacking the duplication and part of the X gene (designated as Sf-rhabdovirus X- ), and cells that were negative for Sf-rhabdovirus...

Due to the pandemic of COVID-19 and subsequent emerging of new mutant strains, there has been a worldwide hunt for therapeutic and protective agents for its inhibition. In this short communication, for the first time, we report the coal-derived carbon quantum dot (CQD) for the possible therapeutic application against SARS-CoV-2. The synthesized C1-CQD is observed to be safe towards the normal cell line at highest dose, while effectively inhibiting growth of SARS-CoV2 (>95%) with IC50 value of 5.469 μg/mL...

During the field surveys in Jiangsu Province, China, contiguous patches of rice plants with varying degrees of dwarfing, wax-white or dark brown enations at the base of stems, and abnormal heading symptoms were observed in the fields located in Jiangning District in Nanjing City, Jurong County in Zhenjiang City, and Zhangjiagang County in Suzhou City. Through molecular analyses, the presence of southern rice black-streaked dwarf virus was confirmed in symptomatic rice plants. The infections of other rice viruses that cause dwarfing were also ruled out...

Enteromorpha polysaccharides (EPPs) have been reported to have antiviral and anti-inflammatory properties. To explore the effect of EPPs on H5N1-infected mice, mice were pretreated with EPPs before being infected with the H5N1 influenza virus intranasally. H5N1 infection resulted in body-weight loss, pulmonary and intestinal damage, and an imbalance of gut microbiota in mice. As a result of the inclusion of EPPs, the body weight of mice recovered and pathological damage to the lung and intestine was reduced...

Sugarcane streak mosaic virus (SCSMV) is one of the major pathogens of sugarcane in the world. Molecular studies and disease management of SCSMV are hindered by the lack of efficient infectious clones. In this study, we successfully constructed Agrobacterium infiltration based infectious clone of SCSMV with different variants. Infectious clones of wild type SCSMV could efficiently infect Nicotiana benthamiana and sugarcane plants resulting in streak and mosaic symptoms on systemic leaves which were further confirmed with RT-PCR and serological assays...

Orthotospoviruses, a genera of negative-sense ssRNA viruses transmitted by thrips, have gained significant attention in recent years due to their detrimental impact on diverse crops, causing substantial economic losses and posing threats to food security. Orthotospoviruses are characterised by a wide range of symptoms in plants, including chlorotic/necrotic spots, vein banding, and fruit deformation. Seven species, including four definite and three tentative species in the genus Orthotospovirus, have so far been documented on the crops of the Indian subcontinent...

Virus-associated infectious diseases are highly detrimental to human health and animal husbandry. Among all countermeasures against infectious diseases, prophylactic vaccines, which developed through traditional or novel approaches, offer potential benefits. More recently, mucosal vaccines attract attention for their extraordinary characteristics compared to conventional parenteral vaccines, particularly for mucosal-related pathogens. Representatively, coronavirus disease 2019 (COVID-19), a respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), further accelerated the research and development efforts for mucosal vaccines by thoroughly investigating existing strategies or involving novel techniques...

African swine fever (ASF) caused by African swine fever virus (ASFV) is a highly infectious and lethal swine disease. Currently, there is only one novel approved vaccine and no antiviral drugs for ASFV. In the study, a high-throughput screening of an FDA-approved drug library was performed to identify several drugs against ASFV infection in primary porcine alveolar macrophages. Triapine and cytarabine hydrochloride were identified as ASFV infection inhibitors in a dose-dependent manner. The two drugs executed their antiviral activity during the replication stage of ASFV...

Bacteriophage Mu is a temperate phage known to infect various species of Enterobacteria, playing a role in bacterial mutation induction and horizontal gene transfer. The phage possesses two types of tail fibers important for host recognition, which enable it to expand its range of hosts. The alternate tail fibers are formed through the action of genes 49-50 or 52-51, allowing the Mu phage to recognize different surfaces of host cells. In a previous study, we presented the X-ray crystal structure of the C-terminal lipopolysaccharide (LPS)-binding domain of gene product (gp) 49, one of the subunits comprising the Mu tail fiber...

Tobacco streak virus induces severe diseases on a wide range of plants and becomes an emerging threat to crop yields. However, the infectious clones of TSV remain to be developed for reverse genetics studies. Here, we obtained the full genome sequence of a TSV-CNB isolate and analyzed the phylogenetic characteristics. Subsequently, we developed the full-length infectious cDNA clones of TSV-CNB driven by 35 S promoter using yeast homologous recombination. Furthermore, the host range of TSV-CNB isolate was determined by Agrobacterium infiltration and mechanical inoculation...