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2.
Emerg Microbes Infect ; 7(1): 10, 2018 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-29410402

RESUMEN

Human adenoviruses (HAdVs) are uniquely important "model organisms" as they have been used to elucidate fundamental biological processes, are recognized as complex pathogens, and are used as remedies for human health. As pathogens, HAdVs may effect asymptomatic or mild and severe symptomatic disease upon their infection of respiratory, ocular, gastrointestinal, and genitourinary systems. High-resolution genomic data have enhanced the understanding of HAdV epidemiology, with recombination recognized as an important and major pathway in the molecular evolution and genesis of emergent HAdV pathogens. To support this view and to actualize an algorithm for identifying, characterizing, and typing novel HAdVs, we determined the DNA sequence of 95 isolates from archives containing historically important pathogens and collections housing currently circulating strains to be sequenced. Of the 85 samples that were completely sequenced, 18 novel recombinants within species HAdV-B and D were identified. Two HAdV-D genomes were found to contain novel penton base and fiber genes with significant divergence from known molecular types. In this data set, we found additional isolates of HAdV-D53 and HAdV-D58, two novel genotypes recognized recently using genomics. This supports the thesis that novel HAdV genotypes are not limited to "one-time" appearances of the prototype but are of importance in HAdV epidemiology. These data underscore the significance of lateral genomic transfer in HAdV evolution and reinforce the potential public health impact of novel genotypes of HAdVs emerging in the population.


Asunto(s)
Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/genética , ADN Viral/genética , Genoma Viral , Genómica , Infecciones por Adenovirus Humanos/epidemiología , Adenovirus Humanos/patogenicidad , Secuencia de Bases , Biología Computacional , Evolución Molecular , Genotipo , Humanos , Filogenia , Recombinación Genética , Análisis de Secuencia de ADN
3.
Sci Rep ; 6: 26311, 2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27212633

RESUMEN

Respiratory Syncytial Virus (RSV) is responsible for considerable morbidity and mortality worldwide and is the most important respiratory viral pathogen in infants. Extensive sequence variability within and between RSV group A and B viruses and the ability of multiple clades and sub-clades of RSV to co-circulate are likely mechanisms contributing to the evasion of herd immunity. Surveillance and large-scale whole-genome sequencing of RSV is currently limited but would help identify its evolutionary dynamics and sites of selective immune evasion. In this study, we performed complete-genome next-generation sequencing of 92 RSV isolates from infants in central Tennessee during the 2012-2014 RSV seasons. We identified multiple co-circulating clades of RSV from both the A and B groups. Each clade is defined by signature N- and O-linked glycosylation patterns. Analyses of specific RSV genes revealed high rates of positive selection in the attachment (G) gene. We identified RSV-A viruses in circulation with and without a recently reported 72-nucleotide G gene sequence duplication. Furthermore, we show evidence of convergent evolution of G gene sequence duplication and fixation over time, which suggests a potential fitness advantage of RSV with the G sequence duplication.


Asunto(s)
Evolución Molecular , Genoma Viral , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/genética , Proteínas del Envoltorio Viral/genética , Teorema de Bayes , Femenino , Duplicación de Gen , Glicosilación , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Estudios Longitudinales , Masculino , Filogenia , Secuencias Repetitivas de Ácidos Nucleicos , Infecciones por Virus Sincitial Respiratorio/epidemiología , Análisis de Secuencia de ARN , Tennessee/epidemiología , Proteínas del Envoltorio Viral/química
4.
BMC Microbiol ; 12: 88, 2012 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-22646228

RESUMEN

BACKGROUND: Ureaplasma urealyticum (UUR) and Ureaplasma parvum (UPA) are sexually transmitted bacteria among humans implicated in a variety of disease states including but not limited to: nongonococcal urethritis, infertility, adverse pregnancy outcomes, chorioamnionitis, and bronchopulmonary dysplasia in neonates. There are 10 distinct serotypes of UUR and 4 of UPA. Efforts to determine whether difference in pathogenic potential exists at the ureaplasma serovar level have been hampered by limitations of antibody-based typing methods, multiple cross-reactions and poor discriminating capacity in clinical samples containing two or more serovars. RESULTS: We determined the genome sequences of the American Type Culture Collection (ATCC) type strains of all UUR and UPA serovars as well as four clinical isolates of UUR for which we were not able to determine serovar designation. UPA serovars had 0.75-0.78 Mbp genomes and UUR serovars were 0.84-0.95 Mbp. The original classification of ureaplasma isolates into distinct serovars was largely based on differences in the major ureaplasma surface antigen called the multiple banded antigen (MBA) and reactions of human and animal sera to the organisms. Whole genome analysis of the 14 serovars and the 4 clinical isolates showed the mba gene was part of a large superfamily, which is a phase variable gene system, and that some serovars have identical sets of mba genes. Most of the differences among serovars are hypothetical genes, and in general the two species and 14 serovars are extremely similar at the genome level. CONCLUSIONS: Comparative genome analysis suggests UUR is more capable of acquiring genes horizontally, which may contribute to its greater virulence for some conditions. The overwhelming evidence of extensive horizontal gene transfer among these organisms from our previous studies combined with our comparative analysis indicates that ureaplasmas exist as quasi-species rather than as stable serovars in their native environment. Therefore, differential pathogenicity and clinical outcome of a ureaplasmal infection is most likely not on the serovar level, but rather may be due to the presence or absence of potential pathogenicity factors in an individual ureaplasma clinical isolate and/or patient to patient differences in terms of autoimmunity and microbiome.


Asunto(s)
ADN Bacteriano/química , ADN Bacteriano/genética , Genoma Bacteriano , Análisis de Secuencia de ADN , Ureaplasma urealyticum/genética , Ureaplasma/genética , Animales , Evolución Molecular , Transferencia de Gen Horizontal , Humanos , Datos de Secuencia Molecular , Ureaplasma/aislamiento & purificación , Ureaplasma urealyticum/aislamiento & purificación , Factores de Virulencia/genética
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