Archives of Virology最新文献

Campylobacter jejuni is a leading cause of foodborne illness worldwide. The application of bacteriophages offers a promising approach to specifically target and reduce C. jejuni contamination in food products. In this study, two C. jejuni phages were characterized, and their ability to inhibit bacterial growth in combination with ethylenediaminetetraacetic acid (EDTA) was investigated. Both phages exhibited tolerance to a wide range of temperature (4–60 °C) and pH (3-9). Phage vB_CjeM-PC10 and vB_CjeM-PC22 were found to have a latent period of 30 min and 20 min and a burst size of 7 and 35 PFU/cell, respectively. Phage vB_CjeM-PC10 has a linear double-stranded DNA (dsDNA) genome of 51,148 bp with 77 ORFs and 29% GC content. Phage vB_CjeM-PC22 has a circular dsDNA genome of 32,543 bp with 56 ORFs and 28% GC content. At 42 °C, the combination of these phages (MOI = 10) and EDTA decreased the count of viable C. jejuni by 5.2 log₁₀ and inhibited the regrowth of resistant cells for 48 h. At 4 °C, phage vB_CjeM-PC10 alone (MOI = 1000) reduced the count of viable C. jejuni by 3 log₁₀ in brain heart infusion (BHI) broth and 2 log₁₀ on chicken skin after incubation for 48 h. Although these phages were effective against C. jejuni, they cannot be utilized directly for food safety applications because they are lysogenic. Nevertheless, these findings expand the genome library of C. jejuni phages and enrich data resources by highlighting potential strategies for controlling C. jejuni infections.

Noroviruses (family Caliciviridae) are common causes of acute gastroenteritis worldwide. Multiple polymerase/capsid combinations have been identified among members of norovirus genogroup GII, at least 10 of which contain GII.P16 polymerase. During hospital-based surveillance (2003–2013) in Russia, we identified eight noroviruses with GII.P16 polymerase – five GII.3[P16], two GII.16[P16], and one GII.5[P16]. This is the first report of the nearly complete genome sequence of a rare recombinant GII.5[P.16] norovirus, which was found in the feces of a child in 2010. Phylogenetic analysis revealed that ORF1 and ORF2/3 of the strain GII.5[P.16]/RUS/Novosibirsk/Nsk-N490/2010 formed separate branches in clusters GII.P16 and GII.5, respectively.

In this study, a novel virus isolated from Nigrospora oryzae, tentatively named "Nigrospora oryzae mycovirus 1" (NoMyV1), was identified. NoMyV1 has a non-segmented dsRNA genome that is 2891 bp in length and contains two non-overlapping open reading frames (ORF1 and 2). ORF1 encodes a protein with sequence similarity to the putative capsid proteins or hypothetical proteins of other unclassified viruses, while ORF2 encodes an RNA-dependent RNA polymerase (RdRp). Sequence comparisons showed that NoMyV1 was most similar to Penicillium janczewskii Beauveria bassiana-like virus 1 (PjBblV1), with 76.12% amino acid sequence identity in the RdRp. In a phylogenetic analysis based on RdRp sequences, NoMyV1 was found to cluster with several other unclassified viruses for which a new genus, "Unirnavirus", which is distinct from the family Partitiviridae, has been proposed. Thus, we conclude that NoMyV1 is a novel member of the proposed genus "Unirnavirus".

Interleukin 1 receptor antagonist (IL1RN) is a competitive inhibitor of interleukin 1 (IL-1). Natural killer cells (NK cells) contribute to the elimination of viruses by their antiviral effector function, which depends on a balance between inhibitory and activating receptor genes such as NKG2D and NKG2A. Using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assays, the association of intronic single-nucleotide polymorphisms (SNPs) in these genes with viral infection were assessed in 111 patients with hepatitis E virus (HEV) infection and 222 HEV-naive healthy controls. An SNP in the IL1RN (VNTR) gene revealed allele 2 to be associated with protection against HEV infection (IL1RN *1/*1 vs. IL1RN *2/*2, OR = 0.26, 95% CI = 0.14–0.47, p < 0.001). Similarly, a polymorphism in the intronic region of NKG2A revealed an association with protection in a co-dominant model (A/A vs. A/G: OR = 0.40; 95% CI = 0.24–0.67; A/A vs. G/G: OR = 0.25; 95% CI = 0.10–0.57; p < 0.05) and an association with susceptibility in a dominant model (A/A + A/G vs. G/G: OR = 2.28; 95% CI = 1.06–4.93; p < 0.05) and a recessive model (AA vs. AG + GG: OR = 2.71; 95% CI = 1.66–4.48; p < 0.001). Our data suggest that genetic polymorphisms in host NKG2A and IL1RN have both protective and detrimental roles in HEV infection, although their impact on disease outcome remains unknown.

Multidrug-resistant infections are becoming increasingly prevalent worldwide. One of the fastest-emerging alternative and adjuvant therapies being proposed is phage therapy. Naturally isolated phages are used in the vast majority of phage therapy treatments today. Engineered phages are being developed to enhance the effectiveness of phage therapy, but concerns over their potential escape remain a salient issue. To address this problem, we designed a biocontained phage system based on conditional replication using amber stop codon suppression. This system can be easily installed on any natural phage with a known genome sequence. To test the system, we individually mutated the start codons of three essential capsid genes in phage φX174 to the amber stop codon (UAG). These phages were able to efficiently infect host cells expressing the amber initiator tRNA, which suppresses the amber stop codon and initiates translation at TAG stop codons. The amber phage mutants were also able to successfully infect host cells and reduce their population on solid agar and liquid culture but could not produce infectious particles in the absence of the amber initiator tRNA or complementing capsid gene. We did not detect any growth-inhibiting effects on E. coli strains known to lack a receptor for φX174 and we showed that engineered phages have a limited propensity for reversion. The approach outlined here may be useful to control engineered phage replication in both the lab and clinic.

A new polerovirus, named “arachis mottle-associated virus” (ArMoV), was identified by high-throughput sequencing in a Pinto peanut (Arachis pintoi) plant. The genome sequence was confirmed by Sanger sequencing and contains 5775 nucleotides and seven predicted open reading frames (ORFs), showing a typical polerovirus genome structure. All of the proteins encoded by ArMoV showed less than 90% amino acid sequence identity to those of other poleroviruses, the threshold to establish a new species in the genus. Phylogenetic analysis based on P1-P2 fusion protein and coat protein amino acid sequences showed that tobacco polerovirus 1 and chickpea chlorotic stunt virus, respectively, were the most closely related to ArMoV. These data suggest that ArMoV is a member of a new species of the genus Polerovirus, for which the binomial name "Polerovirus ARMOV " is proposed.

In this study, we analyzed the dynamic molecular epidemiology of herpangina based on pharyngeal swabs and demographic data collected from children with herpangina monitored in Tongzhou district in China from January 2021 to December 2022. A total of 1022 herpangina cases were diagnosed. Out of 225 samples collected, 56.4% (127/225) were positive for non-polio enterovirus, with seven genotypes identified: coxsackievirus A4 (CV-A4), CV-A6, CV-A10, CV-A2, CV-A16, CV-B3, and CV-A8. The predominant genotypes associated with herpangina changed during and after the COVID-19 pandemic, with the predominant genotypes being CV-A4 and CV-A6 in 2021 and CV-A10 and CV-A6 in 2022.

A novel macluravirus, tentatively named "tsaoko stripe mosaic virus" (TkSMV), was identified in Amomum tsaoko through high-throughput sequencing. The complete genome sequence of TkSMV was determined using RT-PCR and RACE. The genome sequence consists of 8218 nucleotides, excluding the poly(A) tail, and contains a large open reading frame encoding a polyprotein of 2625 amino acids with a molecular weight of approximately 297.13 kDa. TkSMV is most closely related to Alpinia oxyphylla mosaic virus, sharing 71.5% nucleotide and 75.9% amino acid sequence identity. These values are below the species demarcation threshold for the family Potyviridae. These results suggest that TkSMV should be considered a distinct member of the genus Macluravirus.

We present the genome sequence and organization and evidence of persistence of a new picorna-like virus infecting the flatworm Stenostomum leucops. The complete genome sequence belongs to a virus with a positive single-stranded RNA genome with two open reading frames (ORFs) flanked by untranslated regions and a polyadenylated C-terminus. The ORFs encode proteins with conserved motifs typical of members of the order Picornavirales. Phylogenetic analysis confirmed membership in this viral order, and it was found to be closely related to viruses found in Biomphalaria (Mollusca) in France and a virus detected in a metagenomic analysis of water sources from the USA, suggesting widespread distribution. RT-PCR analysis revealed that this virus can be detected in a laboratory-grown worm isolate for at least five years, suggesting persistent infection. However, no apparent deleterious effects were observed in the worms in culture, suggesting a possible commensal relationship between the virus and the worms.