Group A rotaviruses (RVAs) are an important cause of diarrhoeal illness in humans, as well as in mammalian and avian animal species. Previous sequence analyses indicated that avian RVAs are related only distantly to mammalian RVAs. Here, the complete genomes of RVA strain 03V0002E10 from turkey (Meleagris gallopavo) and RVA strain 10V0112H5 from pheasant (Phasianus colchicus) were analysed using a combination of 454 deep sequencing and Sanger sequencing technologies. An adenine-rich insertion similar to that found in the chicken RVA strain 02V0002G3, but considerably shorter, was found in the 39 NCR of the NSP1 gene of the pheasant strain. Most genome segments of both strains were related closely to those of avian RVAs. The novel genotype N10 was assigned to the NSP2 gene of the pheasant RVA, which is related most closely to genotype N6 found in avian RVAs. However, this virus contains a VP4 gene of the novel genotype P [37], which is related most closely to RVAs from pigs, dogs and humans. This strain either may represent an avian/mammalian rotavirus reassortant, or it carries an unusual avian rotavirus VP4 gene, thereby broadening the potential genetic and antigenic variability among RVAs. INTRODUCTIONGroup A rotaviruses (RVAs) are aetiological agents of acute gastroenteritis in humans and animals. They cause severe diarrhoea in infants and children, to which are attributed approximately 453 000 childhood deaths annually (Tate et al., 2012). Recently, two attenuated live vaccines have been introduced and are used successfully for prevention of severe rotavirus-induced disease (Yen et al., 2011).Rotaviruses are classified as a genus within the family Reoviridae (Attoui et al., 2012). They are non-enveloped particles containing a genome of 11 segments of dsRNA with monocistronic coding capacity except for segment 11, which may encode two proteins. Based on antigenic and genome sequence properties, five rotavirus groups (A-E) and two tentative groups (F, G) can be distinguished, which also represent the taxonomically defined rotavirus species and tentative species, respectively (Attoui et al., 2012). In addition, the rotavirus NADRV has been described in adults in Asia (Yang et al., 2004). Recently, a classification system into the eight rotavirus species A-H (with NADRV designated rotavirus H) has been proposed, based on genetic data of genome segment 6 (Matthijnssens et al., 2012).Among the rotavirus groups, RVAs have the highest clinical importance among humans and most mammalian species. The antigenic structures of RVAs eliciting neutralizing antibodies are the outer capsid proteins VP7 and VP4, which define the G-and P-types, respectively. Originally, Gand P-serotypes were defined based on antibody reactivity (Hoshino & Kapikian, 2000). Later on, sequence data of the VP7-and VP4-encoding genome segments were used for definition of G-and P-genotypes, leading to the present list of at least 27 different G-types and 35 different P-types in human and animal RVAs (Matthijnssens et al., 2011). Recently, a genotypi...
A series of 100 Staphylococcus aureus isolates ascribed to sequence type 398 (ST398) and recovered from different sources (healthy carrier and diseased pigs, dust from pig farms, milk, and meat) in Germany were investigated for their virulence and antimicrobial resistance genetic background. Antimicrobial resistance was determined by the disk diffusion method. Virulence and resistance determinants (37 and 31 genes, respectively) were tested by PCR. Only two virulence profiles, including the accessory gene regulator agrI and three or four hemolysin-encoding genes, were detected. In contrast, 33 resistance profiles were distinguished (only 11 were shown by more than one isolate). Fifty-nine isolates were multiresistant (four or more antimicrobial classes), and 98 were methicillin resistant (mecA positive). All of the ST398 isolates showed resistance to tetracycline [encoded by tet(M) alone or together with tet(K) and/or tet(L)]. In addition, 98% were resistant to other antimicrobials, including macrolide-lincosamine-streptogramin B (70%, encoded by ermA, ermB, and ermC, alone or in combination), trimethoprim (65%, mostly due to dfrK and dfrG), kanamycin and gentamicin [29% and 14%, respectively, mainly related to aac(6)-Ie-aph(2؆)-Ia and/or ant(4)-Ia but also to aph(3)-IIIa], chloramphenicol (9%, fexA or cfr), quinupristin-dalfopristin (9%), ciprofloxacin (8%), and trimethoprim-sulfamethoxazole (4%). The heterogeneity of the resistance profiles underlines the ability of the ST398 clone to acquire multiple antimicrobial resistance genes. However, the virulence gene content of the tested isolates was low. Continuous surveillance is needed to clarify whether its pathogenicity potential for animals and humans will increase over time.Methicillin-resistant Staphylococcus aureus (MRSA) of sequence type 398 (ST398) has gained particular attention during recent years because of its association with pigs and its ability to colonize pig farmers and other people in close contact with pigs (7,12,47). The MRSA isolates of ST398 usually lack important virulence determinants that are typical in other community and hospital MRSA isolates. The majority of the ST398 isolates analyzed so far carry only hemolysin-encoding genes (13,21,31,32), although a small number of cases in which the isolates carried the bicomponent leukotoxin PantonValentine (lukPV genes) (43, 49) or staphylococcal enterotoxins (SEs, se genes) (21, 26) have also been reported. Genes for other toxins, like exfoliatins (ET, et genes), leukotoxins, and toxic shock syndrome toxin (TSST-1, tst gene) have not been found yet in ST398 isolates (13,21,31,32,44). The regulation of the expression of most extracellular virulence factors in S. aureus is under the control of a two-component signaling system called the accessory gene regulator (agr), which is polymorphic and divided into four distinct genetic groups (I to IV). A correlation exists between some agr groups and certain pathotypes and clonal complexes (CCs) (48), and CC398 seem to be associated with agr group I (ag...
Hepatitis E is an increasingly reported disease in industrialized countries. Studies on the replication cycle of hepatitis E virus (HEV) are hampered due to the lack of efficient and robust cell culture systems for this virus. We describe the successful isolation of HEV derived from a chronically infected kidney transplant patient held under immunosuppressive therapy. Inoculation of serum sample 47832 onto the human lung carcinoma cell line A549 resulted in the replication of the virus as shown by RT-qPCR. This novel human-derived HEV strain is closely related to a wild boar-derived genotype 3 strain, which did not replicate in A549 cells. It carries a 186 nucleotide insertion in the hypervariable ORF1-region, derived from two parts of its ORF1. By passaging of the infected cells, a cell line continuously producing HEV particles was generated as demonstrated by RT-qPCR, immuno-electron microscopy, density gradient centrifugation and immunohistochemistry. Replication of the produced virus was demonstrated after its inoculation onto fresh A549 cells and two consecutive passages, whereas heating at 65 °C for 2 min abolished its infectivity. Several point mutations scattered along the whole genome were present in the HEV strain from the second passage; however, the ORF1 insertion was still present. Previously, cell culture isolation of two other HEV strains carrying insertions in their hypervariable regions, but originating from human ribosomal protein genes, has been described. The findings may indicate that cell culture adaptation of is mostly dependent on the length and position of the insertion, rather than from the sequence itself.
BackgroundAnimal faeces comprise a community of many different microorganisms including bacteria and viruses. Only scarce information is available about the diversity of viruses present in the faeces of pigs. Here we describe a protocol, which was optimized for the purification of the total fraction of viral particles from pig faeces. The genomes of the purified DNA and RNA viruses were simultaneously amplified by PCR and subjected to deep sequencing followed by bioinformatic analyses. The efficiency of the method was monitored using a process control consisting of three bacteriophages (T4, M13 and MS2) with different morphology and genome types. Defined amounts of the bacteriophages were added to the sample and their abundance was assessed by quantitative PCR during the preparation procedure.ResultsThe procedure was applied to a pooled faecal sample of five pigs. From this sample, 69,613 sequence reads were generated. All of the added bacteriophages were identified by sequence analysis of the reads. In total, 7.7% of the reads showed significant sequence identities with published viral sequences. They mainly originated from bacteriophages (73.9%) and mammalian viruses (23.9%); 0.8% of the sequences showed identities to plant viruses. The most abundant detected porcine viruses were kobuvirus, rotavirus C, astrovirus, enterovirus B, sapovirus and picobirnavirus. In addition, sequences with identities to the chimpanzee stool-associated circular ssDNA virus were identified. Whole genome analysis indicates that this virus, tentatively designated as pig stool-associated circular ssDNA virus (PigSCV), represents a novel pig virus.ConclusionThe established protocol enables the simultaneous detection of DNA and RNA viruses in pig faeces including the identification of so far unknown viruses. It may be applied in studies investigating aetiology, epidemiology and ecology of diseases. The implemented process control serves as quality control, ensures comparability of the method and may be used for further method optimization.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.