scholarly journals The Prevalence and Genetic Characterization of Human Metapneumovirus in Bulgaria, 2016–2019

Intervirology ◽  
2021 ◽  
pp. 1-9
Author(s):  
Neli S. Korsun ◽  
Svetla G. Angelova ◽  
Ivelina T. Trifonova ◽  
Silvia E. Voleva ◽  
Iliana G. Grigorova ◽  
...  
Keyword(s):  
Amino Acid ◽  
Causative Agent ◽  
Respiratory Virus ◽  
Genetic Characterization ◽  
Respiratory Infections ◽  
Prototype Strain ◽  
Human Metapneumovirus ◽  
F Gene ◽  
Hmpv Infection

<b><i>Introduction:</i></b> We investigated the prevalence of human metapneumovirus (hMPV) among patients with acute respiratory infections in Bulgaria, and performed genetic characterization of the F gene of these strains. <b><i>Methods:</i></b> Nasopharyngeal swabs collected from patients of a range of ages were tested by using real-time PCR for 12 respiratory viruses. The F gene was sequenced, and phylogenetic and amino acid analyses of the F gene/protein were performed. <b><i>Results:</i></b> A total of 1,842 patients were examined during a 3-year period; 1,229 patients (66.7%) were positive for at least one respiratory virus. hMPV was identified in 83 (4.5%) patient samples. Eleven (13%) of hMPV-positive patients were coinfected with another respiratory virus. The hMPV incidence rate in the 2016/2017, 2017/2018, and 2018/2019 winter seasons was 5.4, 5.4, and 3.1%, respectively. hMPV was mainly detected in specimens collected between January and May (89.2% of cases). The incidence of hMPV infection was highest (5.1%) among the youngest age-group (0–4 years), where hMPV was a causative agent in 8.1 and 4.8% of bronchiolitis and pneumonia cases, respectively. Among the patients aged ≥5 years, hMPV was detected in 2.2 and 3.2% of cases of pneumonia and central nervous system infections, respectively. Phylogenetic analysis of the F gene showed that the sequenced hMPV strains belonged to the A2b, B1, and B2 genotypes. Numerous amino acid substitutions were identified compared with the NL00/1 prototype strain. <b><i>Conclusion:</i></b> This study revealed the significant role of hMPV as a causative agent of serious respiratory illnesses in early childhood, and also demonstrated year-to-year changes in hMPV prevalence and genetic diversity in circulating strains.

scholarly journals Molecular typing and epidemiologic profiles of human metapneumovirus infection among children with severe acute respiratory infection in Huzhou, China

2021 ◽  
Author(s):  
Lei Ji ◽  
Liping Chen ◽  
Deshun Xu ◽  
Xiaofang Wu
Keyword(s):  
Respiratory Infection ◽  
Acute Respiratory Infection ◽  
Epidemiological Data ◽  
Human Metapneumovirus ◽  
Respiratory Pathogen ◽  
Nasopharyngeal Swab ◽  
F Gene ◽  
Severe Acute Respiratory Infection ◽  
Hmpv Infection ◽  
High Incidence

Abstract Background Human metapneumovirus (hMPV) is one of the important pathogens in infant respiratory tract infection. However, the molecular epidemiology of hMPV among children < 14 years of age hospitalized with severe acute respiratory infection (SARI) is unclear. We investigated the hMPV infection status and genotypes of children hospitalized with SARI from January 2016 to December 2020 in Huzhou, China. Methods A nasopharyngeal flocked swab, nasal wash, or nasopharyngeal swab/or opharyngeal swab combination sample was collected from children with SARI in Huzhou from January 2016 to December 2020. Quantitative reverse transcription-polymerase chain reaction was performed to detect hMPV RNA. The hMPV F gene was amplified and sequenced, followed by analysis using MEGA software (ver. 7.0). Epidemiological data were analyzed using Microsoft Excel 2010 and SPSS (ver. 22.0) software. Results A total of 1133 children with SARI were recruited from 2016 to 2020. Among them, 56 (4.94%) were positive for hMPV-RNA. Children < 5 years of age accounted for 85.71% of the positive cases. The hMPV incidence was high in spring and winter, especially in December and January to March. Phylogenetic analysis of the F-gene sequences of 28 hMPV strains showed that the A1, B1, and B2 genotypes were prevalent in Huzhou, and the dominant hMPV genotype varied according to surveillance year. Conclusions HMPV is an important respiratory pathogen in children in Huzhou, with a high incidence in winter and spring in children < 5 years of age. In this study, genotypes A1, B1, and B2 were the most prevalent.

scholarly journals Immunofluorescence Assay for Detection of Human Metapneumovirus-Specific Antibodies by Use of Baculovirus-Expressed Fusion Protein

2005 ◽  
Vol 12 (1) ◽  
pp. 202-205 ◽  
Author(s):  
Nobuhisa Ishiguro ◽  
Takashi Ebihara ◽  
Rika Endo ◽  
Xiaoming Ma ◽  
Ryo Shirotsuki ◽  
...  
Keyword(s):  
Trichoplusia Ni ◽  
Respiratory Infections ◽  
Recombinant Baculovirus ◽  
Immunofluorescence Assay ◽  
Human Metapneumovirus ◽  
Specific Method ◽  
Serum Samples ◽  
F Protein ◽  
Hmpv Infection ◽  
Well Correlation

ABSTRACT Human metapneumovirus (hMPV) has recently been identified as an etiological agent of acute respiratory infections. The hMPV fusion (F) protein has been indicated to be a major antigenic determinant that mediates effective neutralization and protection against hMPV infection. We developed a new immunofluorescence assay (IFA) using Trichoplusia ni (Tn5) insect cells infected with a recombinant baculovirus-expressing hMPV F protein (Bac-F IFA). A total of 200 serum samples from Japanese people 1 month to 41 years old were tested for immunoglobulin G antibodies to hMPV F protein by Bac-F IFA. The results were compared with those of the conventional IFA based on hMPV-infected LLC-MK2 cells (hMPV IFA). The titers obtained by the two IFAs correlated well (correlation coefficient of 0.88), and the concordance of seroreactivities between the two IFAs was 91% (κ = 0.76). For 192 of the 200 serum samples, the titers obtained by the Bac-F IFA were equal to or higher than those obtained by the hMPV IFA. These results indicated that the Bac-F IFA was more sensitive than the hMPV IFA and that the majority of the antibodies detected by the hMPV IFA reacted with the hMPV F protein. The Bac-F IFA is a more reliable, sensitive, and specific method for the detection of hMPV antibodies than is the hMPV IFA.

scholarly journals Prevalence and Genetic Characterization of Two Mitochondrial Gene Sequences of Strobilocercus Fasciolaris in the Livers of Brown Rats (Rattus norvegicus) in Heilongjiang Province in Northeastern China

2020 ◽  
Vol 10 ◽  
Author(s):  
Fengnian Zhao ◽  
Yun Zhou ◽  
Yanchen Wu ◽  
Kexin Zhou ◽  
Aiqin Liu ◽  
...  
Keyword(s):  
Amino Acid ◽  
Intraspecific Variation ◽  
Rattus Norvegicus ◽  
Genetic Characterization ◽  
Northeastern China ◽  
Amino Acid Sequences ◽  
Morphological Observation ◽  
Heilongjiang Province ◽  
Gene Sequences

Rodents constitute the largest and most successful group of mammals worldwide. Brown rats (Rattus norvegicus) are one of the most common rodent species, and they serve as intermediate hosts of Hydatigera taeniaeformis. Although there have been a few studies reporting on the presence of the larval form of H. taeniaeformis (strobilocercus fasciolaris) in brown rats worldwide, little information is available on the genetic characterization of this parasite, with no molecular data from China. Therefore, from April 2014 to March 2016, this study was carried out to understand the prevalence and genetic characters of strobilocercus fasciolaris in brown rats captured in Heilongjiang Province in northeastern China. The livers of brown rats were collected and examined for the presence of cysts. Each cyst was identified based on morphological observation: the larvae with the naked eye and the scolexes under a microscope. The results were confirmed by polymerase chain reaction (PCR) and sequencing of the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 4 (nad4) genes. At the investigated sites, 11.8% (13/110) of the brown rats were infected with strobilocercus fasciolaris. Based on sequence analysis, there were 10 and six haplotypes regarding the cox1 and the nad4 loci, with 24 and 42 polymorphic sites, respectively (degree of intraspecific variation: 0.3%–4.4% and 0.6%–4.7%, respectively). Twelve nucleotide sequences (six of the 10 at the cox1 locus and all six at the nad4 locus) have not previously been described. Base differences in three of the six novel cox1 gene sequences and five of the six novel nad4 gene sequences caused amino acid changes. Phylogenetic analyses of the cox1 and nad4 gene sequences based on neighbor-joining and Bayesian inference trees indicated that all the strobilocercus fasciolaris isolates belonged to Hydatigera taeniaeformis sensu stricto (s.s.). This is the first report on the genetic characterization of strobilocercus fasciolaris in brown rats in China. The findings of novel cox1 and nad4 nucleotide and amino acid sequences may reflect the region-specific genetic characterization of the parasite. The data will be useful to explore the biological and epidemiological significance of the intraspecific variation within H. taeniaeformis s.s.

scholarly journals Biochemical and Genetic Characterization of Mundticin KS, an Antilisterial Peptide Produced by Enterococcus mundtii NFRI 7393

2002 ◽  
Vol 68 (8) ◽  
pp. 3830-3840 ◽  
Author(s):  
Shinichi Kawamoto ◽  
Jun Shima ◽  
Rumi Sato ◽  
Tomoko Eguchi ◽  
Sadahiro Ohmomo ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Genetic Characterization ◽  
Solid Phase ◽  
Exchange Chromatography ◽  
Nucleotide Sequencing ◽  
Lactobacillus Curvatus ◽  
Amino Acid Peptide ◽  
Enterococcus Mundtii

ABSTRACT Mundticin KS, a bacteriocin produced by Enterococcus mundtii NFRI 7393 isolated from grass silage in Thailand, is active against closely related lactic acid bacteria and the food-borne pathogen Listeria monocytogenes. In this study, biochemical and genetic characterization of mundticin KS was done. Mundticin KS was purified to homogeneity by ammonium sulfate precipitation, sequential ion-exchange chromatography, and solid-phase extraction. The gene cluster (mun locus) for mundticin KS production was cloned, and DNA sequencing revealed that the mun locus consists of three genes, designated munA, munB, and munC. The munA gene encodes a 58-amino-acid mundticin KS precursor, munB encodes a protein of 674 amino acids involved in translocation and processing of the bacteriocin, and munC encodes a mundticin KS immunity protein of 98 amino acids. Amino acid and nucleotide sequencing revealed the complete, unambiguous primary structure of mundticin KS; mundticin KS comprises a 43-amino-acid peptide with an amino acid sequence similar to that of mundticin ATO6 produced by E. mundtii ATO6. Mundticin KS and mundticin ATO6 are distinguished by the inversion of the last two amino acids at their respective C termini. These two mundticins were expressed in Escherichia coli as recombinant peptides and found to be different in activity against certain Lactobacillus strains, such as Lactobacillus plantarum and Lactobacillus curvatus. Mundticin KS was successfully expressed by transformation with the recombinant plasmid containing the mun locus in heterogeneous hosts such as E. faecium, L. curvatus, and Lactococcus lactis. Based on our results, the mun locus is located on a 50-kb plasmid, pML1, of E. mundtii NFRI 7393.

Detection and molecular characterization of porcine enterovirus G15 and teschovirus from India

2020 ◽  
Vol 78 (5) ◽  
Author(s):  
Pradeep Mahadev Sawant ◽  
Nitin Atre ◽  
Abhijeet Kulkarni ◽  
Varanasi Gopalkrishna
Keyword(s):  
Amino Acid ◽  
Complete Genome ◽  
Prototype Strain ◽  
Western India ◽  
Vp1 Gene ◽  
Reading Frame ◽  
Porcine Enterovirus ◽  
Geographical Regions ◽  
Porcine Teschovirus

ABSTRACT Porcine enterovirus G (EV-G) and teschovirus (PTV) generally cause asymptomatic infections. Although both viruses have been reported from various countries, they are rarely detected from India. To detect these viruses in Western India, fecal samples (n = 26) of diarrheic piglets aged below three months from private pig farms near Pune (Maharashtra) were collected. The samples were screened by reverse transcription-polymerase chain reaction using conserved enterovirus specific primers from 5′ untranslated region. For genetic characterization of detected EV-G strain, nearly complete genome, and for PTV, partial VP1 gene were sequenced. EV-G strain showed the highest identity in a VP1 gene at nucleotide (78.61%) and amino acid (88.65%) level with EV-G15, prototype strain. However, its complete genome was homologous with the nucleotide (78.38% identity) and amino acid (91.24% identity) level to Ishi-Ka2 strain (LC316832), unassigned EV-G genotype detected from Japan. The nearly complete genome of EV-G15 consisted of 7398 nucleotides excluding the poly(A) tail and has an open reading frame that encodes a 2170 amino acid polyprotein. Genetic analysis of the partial VP1 gene of teschovirus identified porcine teschovirus 4 (PTV-4) and putative PTV-17 genotype. To the best of our knowledge, this is the first report on nearly full genome characterization of EV-G15, and detection of PTV-4 and putative PTV-17 genotypes from India. Further, detection and characterization of porcine enteroviruses are needed for a comprehensive understanding of their genetic diversity and their association with symptomatic infections from other geographical regions of India.

Genetic characterization of Spermophagus niger (Coleoptera: Chrysomelidae: Bruchinae: Amblycerini) pest associated to seeds of Sorrel (Hibiscus sabdariffa L.) in Burkina Faso

2016 ◽  
Vol 6 (1) ◽  
pp. 07-14
Author(s):  
Jean Christophe Koussoubé ◽  
Fatimata Mbaye ◽  
Cheikh Abdou Khadre Mbacké Dia ◽  
Mbacké Sembène ◽  
Antoine Sanon
Keyword(s):  
Amino Acid ◽  
Burkina Faso ◽  
Genetic Parameters ◽  
Genetic Characterization ◽  
Mitochondrial Gene ◽  
Hibiscus Sabdariffa ◽  
Polymerase Chain ◽  
The One ◽  
First Time

In Burkina Faso, the seeds of sorrel, Hibiscus sabdariffa L. are attacked by a pest identified morphologically as Spermophagus niger which is maintained all year on seeds and causing considerable damages. In the current study, for the first time, genetic characterization for S. niger was performed to determine its genetic identity and place it in its phyletic group. Mitochondrial gene, the Cytochrome oxidase I (COI) of the pest was partially sequenced after extraction and amplification by Polymerase Chain Reaction (PCR). Then the variability of genetic parameters namely the number of polymorphic and monomorphic sites, the frequencies of the different nucleotides and amino acid composition were determined. The nucleotide sequence of S. niger ob-tained was submitted in Genbank and the accession number is KU710716. Nucleotide sequences of S. niger obtained and those of different species of Spermophagus and Z. subfasciatus available in the GenBank database, we determined the percentage of similarity on the one hand and kinship through Phylogenetics reconstructions on the other hand. The results showed the absence of polymorphic sites for 406 sites obtained with 36.5% of thymine, 17.5% of cytosine, adenine 31% and 15% of guanine. Leucine was the majority amino acid (14.50%); the lysine was minority amino acid (0.76%) and cysteine was absent. The percentage of similarity obtained and phylogenetics reconstructions showed that S. niger is very close to the different species of Spermophagus particularly S. drak and different from Z. sub-fasciatus.

scholarly journals Mapping and Characterization of the Primary and Anamnestic H-2d-Restricted Cytotoxic T-Lymphocyte Response in Mice against Human Metapneumovirus

2007 ◽  
Vol 81 (20) ◽  
pp. 11461-11467 ◽  
Author(s):  
Guillermina A. Melendi ◽  
Fidel Zavala ◽  
Ursula J. Buchholz ◽  
Guy Boivin ◽  
Peter L. Collins ◽  
...  
Keyword(s):  
Cytotoxic T Lymphocyte ◽  
Respiratory Infections ◽  
Human Metapneumovirus ◽  
Lymphocyte Response ◽  
Ctl Response ◽  
T Cell Lines ◽  
Dominant Epitope ◽  
Cytotoxic T Lymphocyte Response ◽  
Subdominant Epitope

ABSTRACT Cytotoxic T lymphocytes (CTLs) are important for the control of virus replication during respiratory infections. For human metapneumovirus (hMPV), an H-2d-restricted CTL epitope in the M2-2 protein has been described. In this study, we screened the hMPV F, G, N, M, M2-1, and M2-2 proteins using three independent algorithms to predict H-2d CTL epitopes in BALB/c mice. A dominant epitope (GYIDDNQSI) in positions 81 to 89 of the antitermination factor M2-1 and a subdominant epitope (SPKAGLLSL) in N307-315 were detected during the anti-hMPV CTL response. Passive transfer of CD8+ T-cell lines against M2-181-89 and N307-315 protected Rag1−/− mice against hMPV challenge. Interestingly, diversification of CTL targets to include multiple epitopes was observed after repetitive infections. A subdominant response against the previously described M2-2 epitope was detected after the third infection. An understanding of the CTL response against hMPV is important for developing preventive and therapeutic strategies against the virus.

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