Unique Amino Acid Research Articles

Molecular characterization of Canna yellow streak virus with divergent coat protein N-terminal fragment in Iraq.

Canna yellow streak virus (CaYSV,familyPotyviridae)infects many canna cultivars, which have been widely cultivated in the Iraqi gardens for ornamental purposes. The genetic variability within multiple genomic regions of CaYSV population has been demonstrated in the 3' part, particularly in the coat protein (CP). This work was aimed to characterize CaYSV and investigate its variability from canna plants in Iraq. Leaves of canna plants grown in severalgardens in Baghdad were tested by potyvirus group antibodies and RT-PCR. Analysis of the nucleotide (nt) sequences corresponding to the 3' part of the virus genomerevealed the highest identity (81.6-90.6%) with known CaYSV isolates. Phylogenetic analysis of the coat protein (CP) genesequence placed the Iraqiisolates in a separate clade with members of group A. This distinction was evidenced by unique amino acid changes found within the N-terminal motif of the CP. This is the first report of phylogenetically distinct CaYSV in Iraq. This is the first report of phylogenetically distinct CaYSV with divergent CP N-terminus in Iraq.

Molecular surveillance of equine parvovirus-hepatitis from oral, nasal, vaginal, and semen specimens collected from horses living in Korea.

Equine parvovirus-hepatitis (EqPV-H) is one of the etiological agents of Theiler's disease, causing fulminant hepatitis; however, its transmission route and pathogenesis remain unclear. In the present study, we aimed to determine EqPV-H shedding in oral/nasal/vaginal swabs or semen samples from horses living in Korea using nested polymerase chain reaction. We then used the data obtained to investigate various risk factors associated with EqPV-H including viral shedding, hepatopathological changes, and genetic diversity. Our data revealed occurrence of EqPV-H shedding in these animals (oral: 3/102 [2.9%]; nasal: 3/102 [2.9%]; semen: 1/9 [11.1%]) and identified that both age and country of foaling were significantly associated with EqPV-H shedding (p<.05). In addition, we noted that one of the newly isolated strains clustered separately from the other strains in the phylogenetic tree, revealing unique nucleotide and amino acid substitutions. This is a field surveillance study providing evidence of natural and venereal shedding of EqPV-H and describing its presence in both oral/nasal fluids and semen. This epidemiological and clinical analysis may help specify the clinicopathological features of EqPV-H and facilitate the development of novel disease prevention strategies.

Screening of xanthine oxidase inhibitory peptides by ligand fishing and molecular docking technology

Gout, as the second major metabolic disease after cardiovascular disease. Peptides have the advantages of natural and no side effects in the treatment and prevention of gout. This study aimed to screen xanthine oxidase (XOD) inhibitory peptides from Scophthalmus maximus protein as a drug basis for the treatment of gout. The specific results are as follows: Immobilization of xanthine oxidase 25.564 μg/mg by modified magnetic beads, and modified magnetic beads can be reused three times. Three decapeptides (FSLVHYAGTV, FTNEKLQQFF and WDDMEKIWHH) were screened, the IC50 were 3.741, 4.046 and 2.203 mg/mL. Circular dichroism and three-dimensional fluorescence spectra showed that the inhibitory peptide would change the helical structure of XOD and the internal hydrophobic environment. Molecular docking showed that the inhibitory effect of inhibitory peptides depends on the number of unique amino acid residues in the active center of XOD enzyme. In conclusion, this study provides a method for screening anti-gout peptides, which not only solves the problem of treating gout, but also realizes the high-value utilization of marine products. In addition, this method has substantial application value because of its low cost and simple operation.

Characterization of avain metapneumovirus subgroup C isolated from chickens in Beijing, China

Avian metapneumovirus (aMPV) is an important causative agent that causes acute respiratory disease and egg-dropping in chickens and turkeys. Here, we characterized an aMPV subgroup C (aMPV/C) from 320-day-old broiler breeder chickens with severe respiratory diseases in Beijing, China, as evidenced by RT-PCR typing and confirmation of the nucleoprotein (N) gene sequence. The N gene sequence of the aMPV/C strain (designated BJ17) exhibited no deletions or insertions and possessed 94.6% to 99.6% identity to those of published aMPV/C isolates. The phylogenetic tree of the nucleotide sequences constructed using the neighbor-joining clustering method showed that the BJ17 strain formed one cluster with other aMPV/C viruses and formed one subcluster with published Chinese aMPV/C isolates regardless of Muscovy duck or chicken origins. Comparative analysis of the N proteins showed that a unique amino acid residue D at position 110 might be associated with regional distribution due to its occurrence in all the Chinese aMPV/C isolates only. Strain BJ17 was successfully isolated by cultured Vero cell passage and further inoculated in 3-wk-old specific-pathogen-free chickens for the examination of pathogenicity. Animal experimental results showed that BJ17-inoculated chickens had severe respiratory diseases and inflammatory lesions, as demonstrated by pathological changes and aMPV antigen in the nasal turbinate, tracheae, and lung tissues. These results enrich the available information regarding the epidemiology and pathogenicity of aMPV/C in chickens, which may facilitate the development of effective measures against aMPV/C infection in China.

FgMet3 and FgMet14 related to cysteine and methionine biosynthesis regulate vegetative growth, sexual reproduction, pathogenicity, and sensitivity to fungicides in Fusarium graminearum

Fusarium graminearum is a destructive filamentous fungus, which widely exists in wheat and other cereal crops. Cysteine and Methionine are unique sulfur-containing amino acids that play an essential role in protein synthesis and cell life, but their functions and regulation in F. graminearum remain largely unknown. Here we identified two proteins, FgMet3 and FgMet14 in F. graminearum, which are related to the synthesis of cysteine and methionine. We found FgMet3 and FgMet14 were localized to the cytoplasm and there was an interaction between them. FgMet3 or FgMet14 deletion mutants (ΔFgMet3 and ΔFgMet14) were deficient in vegetative growth, pigment formation, sexual development, penetrability and pathogenicity. With exogenous addition of cysteine and methionine, the vegetative growth and penetrability could be completely restored in ΔFgMet3 and ΔFgMet14, while sexual reproduction could be fully restored in ΔFgMet3 and partially restored in ΔFgMet14. ΔFgMet3 and ΔFgMet14 exhibited decreased sensitivity to Congo red stress and increased sensitivity to SDS, NaCl, KCl, Sorbitol, Menadione, and Zn ion stresses. Moreover, FgMet3 and FgMet14 nonspecifically regulate the sensitivity of F. graminearum to fungicides. In conclusion, FgMet3 and FgMet14 interacted to jointly regulate the development, pathogenicity, pigment formation, sensitivity to fungicides and stress factors in F. graminearum.

Unique CagL Amino Acid Polymorphism Patterns of Helicobacter pylori in Peptic Ulcer and Non-Ulcer Dyspepsia

Unique CagL Amino Acid Polymorphism Patterns of Helicobacter pylori in Peptic Ulcer and Non-Ulcer Dyspepsia

Plasma Amino Acid Concentrations in Children With Severe Malaria Are Associated With Mortality and Worse Long-term Kidney and Cognitive Outcomes.

Global changes in amino acid levels have been described in severe malaria (SM), but the relationship between amino acids and long-term outcomes in SM has not been evaluated. We measured enrollment plasma concentrations of 20 amino acids using high-performance liquid chromatography in 500 Ugandan children aged 18 months to 12 years, including 122 community children and 378 children with SM. The Kidney Disease: Improving Global Outcomes criteria were used to define acute kidney injury (AKI) at enrollment and chronic kidney disease (CKD) at 1-year follow-up. Cognition was assessed over 2 years of follow-up. Compared to laboratory-defined, age-specific reference ranges, there were deficiencies in sulfur-containing amino acids (methionine, cysteine) in both community children and children with SM. Among children with SM, global changes in amino acid concentrations were observed in the context of metabolic complications including acidosis and AKI. Increases in threonine, leucine, and valine were associated with in-hospital mortality, while increases in methionine, tyrosine, lysine, and phenylalanine were associated with postdischarge mortality and CKD. Increases in glycine and asparagine were associated with worse attention in children <5 years of age. Among children with SM, unique amino acid profiles are associated with mortality, CKD, and worse attention.

The acidic amino acid-rich C-terminal domain of VanabinX enhances reductase activity, attaining 1.3- to 1.7-fold vanadium reduction

Ascidians accumulate extremely high levels of vanadium (V) in their blood cells. Several V-related proteins, including V-binding proteins (vanabins), have been isolated from V-accumulating ascidians. In this study, to obtain a deeper understanding of vanabins, we performed de novo transcriptome analysis of blood cells from a V-rich ascidian, Ascidia sydneiensis samea, and constructed a database containing 8532 predicted proteins. We found a novel vanabin with a unique acidic amino acid–rich C-terminal domain, designated VanabinX, in the database and studied it in detail. Reverse-transcription polymerase chain reaction analysis revealed that VanabinX was detected in all adult tissues examined, and was most prominent in blood cells and muscle tissue. We prepared recombinant proteins and performed immobilized metal ion affinity chromatography and a NADPH-coupled V(V)-reductase assay. VanabinX bound to metal ions, with increasing affinity for Cu(II) > Zn(II) > Co(II), but not to V(IV). VanabinX reduced V(V) to V(IV) at a rate of 0.170 μM per micoromolar protein within 30 min. The C-terminal acidic domain enhanced the reduction of V(V) by Vanabin2 to 1.3-fold and of VanabinX itself to 1.7-fold in trans mode. In summary, we constructed a protein database containing 8532 predicted proteins expressed in blood cells; among them, we discovered a novel vanabin, VanabinX, which enhances V reduction by vanabins.

Adipose stem cells preincubated with theanine exert liver regeneration through increase of stem cell paracrine VEGF and suppression of ROS, pyroptosis as well as autophagy markers in liver damage induced by N-nitrosodiethylamine

AimsLiver diseases induce a severe decrease in quality of life. Stem cell based therapy shows therapeutic potential in the treatment of liver injury. Theanine is a unique amino acid found in green tea and could confer beneficial effects on cell protection. This study investigates if protective effect on the liver by stem cells preincubated with theanine is better than that from stem cells without preincubated theanine. MethodsWe transplanted theanine preincubated adipose-derived stem cells (ADSC) to male Wistar rats with liver dysfunction induced by N-nitrosodiethylamine. The viability, migration and antioxidant capabilities were performed in the ADSC pre-incubated with theanine. Hepatic functional, structural and molecular assays were determined in the animals with or without theanine preincubated ADSC. Key findingsCell model revealed that ADSC preincubated with green tea theanine (T-ADSC) increased cell capabilities including viability, migration and paracrine secretion. In vivo results indicated that several pathological conditions were observed in rats with liver injury induced by DEN including structural changes and expression of pyroptosis as well as autophagy markers. The above pathological conditions were improved when the rats received both ADSC and T-ADSC treatment. Furthermore, T-ADSC showed better therapeutic effect on rats with liver injury than ADSC due to significant suppression of pyroptosis markers caspase-1 and IL-1β as well as autophagy marker LC3-II accompanied with intensive paracrine VEGF from T-ADSC. SignificanceIncreased paracrine VEGF secretion from T-ADSC plays a crucial role in liver regeneration. A future clinical study may be designed for further verification of these experimental in vivo findings.

Recent strains of influenza D virus create a new genetic cluster for European strains

Bovine respiratory diseases (BRD) are one of the significant health problems for cattle breeding industry. Influenza D virus (IDV) alone or in combination with other respiratory pathogens plays a role in BRD. According to the IDV-HEF gene region, phylogenetic analyzes revealed five lineages: D/OK, D/660, D/Yama2016, D/Yama2019, and D/CA2019, so far. In this study, despite no success in virus isolation, the presence of IDV was investigated by RT-PCR (partial HEF gene region) in 219 nasal swab samples collected from cattle with BRD between 2012 and 2021. The presence of IDV was demonstrated in two samples, and genome characterization data of the IDV sequences both in the partial and complete HEF gene regions showed that one of the obtained sequences (D/bovine/Turkey-Bursa/ET-138/2021) was in the lineage D/Yama2019 while the other (D/bovine/Turkey-Bursa/ET-130/2013) created a new lineage tentatively called D/Bursa2013 as including few partial IDV sequences reported in Europe. Two nucleotide substitutions (nt252A→G, nt299T→C) were typically characterized for the tentative lineage D/Bursa2013, one of which also leads to a unique amino acid change at position aa100 (V→A). When the amino acid differences between the lineages were evaluated, amino acid substitution changes were detected in four regions [aa12 (Alanine→Aspartic acid), aa19 (Glycine→Arginine), aa22 (Proline→Serine), and aa110 (Aspargine→Arginine)] of the D/Yama2019 lineage, unlike the other lineages. Considering the most common D/OK lineage in Europe, many nucleotide substitutions were shown between D/OK and D/Bursa2013. Accordingly, aminoacid substitutions were observed in aa27 (Threonine→Asparagine) and aa100 (Valine→Alanine) in the D/bovine/Turkey-Bursa/ET-138/2021 sequence. Study results describe the circulation of D/Yama2019 and D/Bursa2013 (new lineage) in Turkey. Expansion of new strains seems possible due to the high mutation rate of influenza viruses. It is important to understand the development of IDV with comprehensive characterization studies.

Optimization of a Calcium-Based Treatment Method for Jellyfish to Design Food for the Future.

Edible jellyfish are a traditional Southeast Asian food, usually prepared as a rehydrated product using a salt and alum mixture, whereas they are uncommon in Western Countries and considered as a novel food in Europe. Here, a recently developed, new approach for jellyfish processing and stabilization with calcium salt brining was upgraded by modifying the pre-treatment step of freshly caught jellyfish and successfully applied to several edible species. Treated jellyfish obtained by the application of the optimized version of this method respected both quality and safety parameters set by EU law, including no pathogenic microorganisms, absence or negligible levels of histamine and of total volatile basic nitrogen, no heavy metals; and the total bacterial, yeast, and mold counts were either negligible or undetectable. Jellyfish treated by the presented method exhibited unique protein content, amino acid and fatty acid profiles, antioxidant activity, and texture. The optimized method, initially set up on Rhiszostoma pulmo, was also successfully applied to other edible jellyfish species (such as Cotylorhiza tuberculata, Phyllorhiza punctata, and Rhopilema nomadica) present in the Mediterranean Sea. This study discloses an innovative process for the preparation of jellyfish-based food products for potential future distribution in Europe.

A Review of the Health Benefits of Tea: Implications of the Biochemical Properties of the Bioactive Constituents

Tea is the second-most drank and refreshing beverage after water since the time immemorial. Tea harbours more than 700 bioactive compounds viz, different classes of polyphenols, unique amino acid L-Theanine, alkaloids (Caffeine, Theobromine), and Volatile Flavor Compounds (VFC). Tea's polyphenols make its inherent therapeutic potential unlimited. Tea's significance in managing cancer, diabetes, stomach ulcer, influenza, neurological diseases, etc. is well-documented. However, advantageous biochemical capabilities of tea have yet to be fully utilised. Hence, this review aims at to examine tea's variety, drinking habits, biochemistry, and therapeutic qualities. A number of significant online resources, including Google Scholar, PubMed, Science Direct, and others, were searched for various research works on tea and its health-promoting qualities by using keywords like tea, health benefits, bioactive components against diseases, etc. Current review highlighted that drinking a cup or more green tea is recommended for improving antioxidant status and to manage diabetes and obesity related problem. However after detailed review work on tea it become clear that not only green tea but also other varies of tea like black, white tea are also harbour lots of bioactive molecules since they are processed from same plant. Tea improves antioxidant status and manages diabetes and obesity. It also helps prevent and cure, heart disease, malignancy, digestive dysfunction, and metabolic disorders including obesity and diabetes. Epigallocatechin Gallate (EGCG), found in tea, has been shown to reduce complications from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV 2) infection. When taken in its traditional form to manage ailments, tea is sometimes controversial due to a lack of confirming evidence of its benefits. The paper covers the numerous health advantages of tea, focusing on the specific components contributing to such benefits, and stresses the value of diverse brewing processes.

L-theanine exuded from Camellia sinensis roots regulates element cycling in soil by shaping the rhizosphere microbiome assembly

Root exudate metabolites are a key medium for the interaction between plants and soil microbiota. L-theanine is a unique non-protein amino acid critical for the flavor and potential health benefits of tea products; however, its biological function in tea plants is not well understood. As L-theanine is mainly synthesized in the roots of tea plants, we hypothesized that L-theanine could affect the function of the rhizosphere microbiota by modulating microbial assembly. In the present study, L-theanine was detected in the exudates of tea plant roots using liquid chromatography-mass spectrometry. Additionally, 16S rRNA gene sequencing revealed that L-theanine significantly altered the structure of the rhizosphere microbiota and selectively shaped rhizosphere microbial assembly. Moreover, metagenomic data showed that L-theanine affected the abundance of genes encoding element cycling in soil. Interestingly, the denitrification and complete nitrification pathways were significantly inhibited by L-theanine by decreasing the narH, napA, and napB genes abundance. These findings provide new insights into the biological function of L-theanine, as well as the implications of interactions between tea plant root exudates and the rhizosphere microbiome.

Identification of a Novel Pseudo-Natural Product Type IV IDO1 Inhibitor Chemotype.

Natural product (NP)-inspired design principles provide invaluable guidance for bioactive compound discovery. Pseudo-natural products (PNPs) are de novo combinations of NP fragments to target biologically relevant chemical space not covered by NPs. We describe the design and synthesis of apoxidoles, a novel pseudo-NP class, whereby indole- and tetrahydropyridine fragments are linked in monopodal connectivity not found in nature. Apoxidoles are efficiently accessible by an enantioselective [4+2] annulation reaction. Biological evaluation revealed that apoxidoles define a new potent type IV inhibitor chemotype of indoleamine 2,3-dioxygenase 1 (IDO1), a heme-containing enzyme considered a target for the treatment of neurodegeneration, autoimmunity and cancer. Apoxidoles target apo-IDO1, prevent heme binding and induce unique amino acid positioning as revealed by crystal structure analysis. Novel type IV apo-IDO1 inhibitors are in high demand, and apoxidoles may provide new opportunities for chemical biology and medicinal chemistry research.

Identification of a Novel Pseudo‐Natural Product Type IV IDO1 Inhibitor Chemotype

AbstractNatural product (NP)‐inspired design principles provide invaluable guidance for bioactive compound discovery. Pseudo‐natural products (PNPs) are de novo combinations of NP fragments to target biologically relevant chemical space not covered by NPs. We describe the design and synthesis of apoxidoles, a novel pseudo‐NP class, whereby indole‐ and tetrahydropyridine fragments are linked in monopodal connectivity not found in nature. Apoxidoles are efficiently accessible by an enantioselective [4+2] annulation reaction. Biological evaluation revealed that apoxidoles define a new potent type IV inhibitor chemotype of indoleamine 2,3‐dioxygenase 1 (IDO1), a heme‐containing enzyme considered a target for the treatment of neurodegeneration, autoimmunity and cancer. Apoxidoles target apo‐IDO1, prevent heme binding and induce unique amino acid positioning as revealed by crystal structure analysis. Novel type IV apo‐IDO1 inhibitors are in high demand, and apoxidoles may provide new opportunities for chemical biology and medicinal chemistry research.

Ascorbic Acid (Vitamin C) as a Cosmeceutical to Increase Dermal Collagen for Skin Antiaging Purposes: Emerging Combination Therapies.

Ascorbic acid (AA) is an essential nutrient and has great potential as a cosmeceutical that protects the health and beauty of the skin. AA is expected to attenuate photoaging and the natural aging of the skin by reducing oxidative stress caused by external and internal factors and by promoting collagen gene expression and maturation. In this review, the biochemical basis of AA associated with collagen metabolism and clinical evidence of AA in increasing dermal collagen and inhibiting skin aging were discussed. In addition, we reviewed emerging strategies that have been developed to overcome the shortcomings of AA as a cosmeceutical and achieve maximum efficacy. Because extracellular matrix proteins, such as collagen, have unique amino acid compositions, their production in cells is influenced by the availability of specific amino acids. For example, glycine residues occupy 1/3 of amino acid residues in collagen protein, and the supply of glycine can be a limiting factor for collagen synthesis. Experiments showed that glycinamide was the most effective among the various amino acids and amidated amino acids in stimulating collagen production in human dermal fibroblasts. Thus, it is possible to synergistically improve collagen synthesis by combining AA analogs and amino acid analogs that act at different stages of the collagen production process. This combination therapy would be useful for skin antiaging that requires enhanced collagen production.

Phenotypic and Genetic Studies of the Viral Lineage Associated with the Recent Yellow Fever Outbreak in Brazil.

Yellow fever virus (YFV) caused an outbreak in the Brazilian Southeast from 2016 to 2019, of the most significant magnitude since the 1900s. An investigation of the circulating virus revealed that most of the genomes detected in this period carried nine unique amino acid polymorphisms, with eight located in the non-structural proteins NS3 and NS5, which are pivotal for viral replication. To elucidate the effect of these amino acid changes on viral infection, we constructed viruses carrying amino acid alterations in NS3 and NS5, performed infection in different cells, and assessed their neurovirulence in BALB/c mice and infected AG129 mice. We observed that the residues that compose the YFV 2016–2019 molecular signature in the NS5 protein might have been related to an attenuated phenotype, and that the alterations in the NS3 protein only slightly affected viral infection in AG129 mice, increasing to a low extent the mortality rate of these animals. These results contributed to unveiling the role of specific naturally occurring amino acid changes in the circulating strain of YFV in Brazil.

Resource Utilization of Bovine Neck Ligament: Enzymatic Preparation of Elastin Peptide and Its Antioxidant Activity.

Elastin is considered an excellent resource for obtaining antioxidant peptides due to unique amino acid composition. However, it is hardly soluble in water or in dilute acid or alkali; most of the elastases have low yields for preparing elastin peptides, making it difficult to meet industrial applications. To address above problems, enzymes capable of hydrolyzing elastin into soluble peptides were preferred from typical commercial protease preparations. The optimal enzymatic hydrolysis process conditions for elastin peptides were obtained by response surface optimization design. The molecular weight, amino acid composition, and antioxidant activity of the enzymatic hydrolysis products were determined. The results show that the alkaline protease NUE has a strong hydrolysis effect. The optimized enzymatic hydrolysis conditions are as follows: substrate concentration is 5%, enzyme concentration is 650 U/mL, pH is 10.0, temperature is 60°C, time is 6h. The degree of hydrolysis of elastic protein peptides obtained through this method is 14.42%. The distribution of molecular weight is 200-6500Da, more than 85% of the component molecular amount is greater than 800Da; the amino acid content related to antioxidant activity has reached 68mg/100mg, so it has extremely high free radical clearance. Compared with acid and alkali methods, the anti-oxidation capacity of enzyme-based peptide is better, the reaction conditions are milder, the yield is higher, and by-products and pollutants are fewer. It provides an effective way to industrialized production of elastin peptides with high antioxidant activity and a basis for its widespread application in the food and pharmaceutical industries.

Long Term Norovirus Infection in a Patient with Severe Common Variable Immunodeficiency.

Norovirus is the most common cause of acute non-bacterial gastroenteritis. Immunocompromised patients can become chronically infected, with or without symptoms. In Europe, common variable immunodeficiency (CVID) is one of the most common inborn errors of immunity. A potentially severe complication is CVID-associated enteropathy, a disorder with similar histopathology to celiac disease. Studies suggest that chronic norovirus infection may be a contributor to CVID enteropathy, and that the antiviral drug ribavirin can be effective against norovirus. Here, a patient with CVID-like disease with combined B- and T-cell deficiency, had chronic norovirus infection and enteropathy. The patient was routinely administered subcutaneous and intravenous immunoglobulin replacement therapy (SCIg and IVIg). The patient was also administered ribavirin for ~7.5 months to clear the infection. Stool samples (collected 2013–2016) and archived paraffin embedded duodenal biopsies were screened for norovirus by qPCR, confirming a chronic infection. Norovirus genotyping was done in 25 stool samples. For evolutionary analysis, the capsid (VP1) and polymerase (RdRp) genes were sequenced in 10 and 12 stool samples, respectively, collected before, during, and after ribavirin treatment. Secretor phenotyping was done in saliva, and serum was analyzed for histo-blood group antigen (HBGA) blocking titers. The chronic norovirus strain formed a unique variant subcluster, with GII.4 Den Haag [P4] variant, circulating around 2009, as the most recent common ancestor. This corresponded to the documented debut of symptoms. The patient was a secretor and had HBGA blocking titers associated with protection in immunocompetent individuals. Several unique amino acid substitutions were detected in immunodominant epitopes of VP1. However, HBGA binding sites were conserved. Ribavirin failed in treating the infection and no clear association between ribavirin-levels and quantity of norovirus shedding was observed. In conclusion, long term infection with norovirus in a patient with severe CVID led to the evolution of a unique norovirus strain with amino acid substitutions in immunodominant epitopes, but conservation within HBGA binding pockets. Regularly administered SCIg, IVIg, and ~7.5-month ribavirin treatment failed to clear the infection.

Serological Investigation and Genetic Characteristics of Pseudorabies Virus between 2019 and 2021 in Henan Province of China

In late 2011, severe pseudorabies (PR) outbreaks occurred among swine herds vaccinated with the Bartha-K61 vaccine in many provinces of China, causing enormous economic losses for the pork industry. To understand the epidemic profile and genetic characteristics of the pseudorabies virus (PRV), a total of 35,796 serum samples were collected from 1090 pig farms of different breeding scales between 2019 and 2021 in the Henan province where swine had been immunized with the Bartha-K61 vaccine, and PRV glycoprotein E (gE)-specific antibodies were detected using an enzyme-linked immunosorbent assay (ELISA). The results reveal that the overall positive rate for PRV gE antibodies was 20.33% (7276/35,796), which decreased from 25.00% (2596/10,385) in 2019 to 16.69% (2222/13,315) in 2021, demonstrating that PR still existed widely in pig herds in the Henan province but displayed a decreasing trend. Further analysis suggested that the PRV-seropositive rate may be associated with farm size, farm category, quarter, region and the cross-regional transportation of livestock. Moreover, the gE gene complete sequences of 18 PRV isolates were obtained, and they shared a high identity (97.1–100.0%) with reference strains at the nucleotide level. Interestingly, the phylogenetic analysis based on the gE complete sequences found that there were both classical strains and variant strains in pig herds. The deduced amino acid sequence analysis of the gE gene showed that there were unique amino acids in the classical strains, the variant strains and genotype Ⅱ strains. This study provides epidemiological data that could be useful in the prevention of pseudorabies in Henan, China, and this finding contributed to our understanding of the epidemiology and evolution of PRV.