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2.
Microbiol Resour Announc ; 11(5): e0009522, 2022 May 19.
Article in English | MEDLINE | ID: mdl-35389260

ABSTRACT

The genome sequences of five strains of a mammarenavirus were assembled from metagenomic data from pygmy mice (Mus minutoides) captured in Sierra Leone. The nearest fully sequenced relatives of this virus, which was named Seli virus, are lymphocytic choriomeningitis virus, Lunk virus, and Ryukyu virus.

3.
PLoS One ; 16(6): e0253578, 2021.
Article in English | MEDLINE | ID: mdl-34166421

ABSTRACT

RATIONALE: There is little doubt that aerosols play a major role in the transmission of SARS-CoV-2. The significance of the presence and infectivity of this virus on environmental surfaces, especially in a hospital setting, remains less clear. OBJECTIVES: We aimed to analyze surface swabs for SARS-CoV-2 RNA and infectivity, and to determine their suitability for sequence analysis. METHODS: Samples were collected during two waves of COVID-19 at the University of California, Davis Medical Center, in COVID-19 patient serving and staff congregation areas. qRT-PCR positive samples were investigated in Vero cell cultures for cytopathic effects and phylogenetically assessed by whole genome sequencing. MEASUREMENTS AND MAIN RESULTS: Improved cleaning and patient management practices between April and August 2020 were associated with a substantial reduction of SARS-CoV-2 qRT-PCR positivity (from 11% to 2%) in hospital surface samples. Even though we recovered near-complete genome sequences in some, none of the positive samples (11 of 224 total) caused cytopathic effects in cultured cells suggesting this nucleic acid was either not associated with intact virions, or they were present in insufficient numbers for infectivity. Phylogenetic analysis suggested that the SARS-CoV-2 genomes of the positive samples were derived from hospitalized patients. Genomic sequences isolated from qRT-PCR negative samples indicate a superior sensitivity of viral detection by sequencing. CONCLUSIONS: This study confirms the low likelihood that SARS-CoV-2 contamination on hospital surfaces contains infectious virus, disputing the importance of fomites in COVID-19 transmission. Ours is the first report on recovering near-complete SARS-CoV-2 genome sequences directly from environmental surface swabs.


Subject(s)
COVID-19/genetics , Genome, Viral , Hospitals, Teaching , Phylogeny , SARS-CoV-2/genetics , Sequence Analysis, RNA , Animals , COVID-19/epidemiology , COVID-19/transmission , Chlorocebus aethiops , Humans , SARS-CoV-2/isolation & purification , Vero Cells
4.
One Health Outlook ; 2(1): 21, 2020.
Article in English | MEDLINE | ID: mdl-33169111

ABSTRACT

BACKGROUND: The second largest Ebola virus disease (EVD) outbreak began in the Democratic Republic of Congo in July 2018 in North Kivu Province. Data suggest the outbreak is not epidemiologically linked to the 2018 outbreak in Equateur Province, and that independent introduction of Ebola virus (EBOV) into humans occurred. We tested for antibodies to ebolaviruses in febrile patients seeking care in North Kivu Province prior to the EVD outbreak. METHODS: Patients were enrolled between May 2017 and April 2018, before the declared start of the outbreak in eastern DRC. Questionnaires were administered to collect demographic and behavioural information to identify risk factors for exposure. Biological samples were evaluated for ebolavirus nucleic acid, and for antibodies to ebolaviruses. Prevalence of exposure was calculated, and demographic factors evaluated for associations with ebolavirus serostatus. RESULTS: Samples were collected and tested from 272 people seeking care in the Rutshuru Health Zone in North Kivu Province. All patients were negative for filoviruses by PCR. Intial screening by indirect ELISA found that 30 people were reactive to EBOV-rGP. Results were supported by detection of ebolavirus reactive linear peptides using the Serochip platform. Differential screening of all reactive serum samples against the rGP of all six ebolaviruses and Marburg virus (MARV) showed that 29 people exhibited the strongest reactivity to EBOV and one to Bombali virus (BOMV), and western blotting confirmed results. Titers ranged from 1:100 to 1:12,800. Although both sexes and all ages tested positive for antibodies, women were significantly more likely to be positive and the majority of positives were in February 2018. CONCLUSIONS: We provide the first documented evidence of exposure to Ebola virus in people in eastern DRC. We detected antibodies to EBOV in 10% of febrile patients seeking healthcare prior to the declaration of the 2018-2020 outbreak, suggesting early cases may have been missed or exposure ocurred without associated illness. We also report the first known detection of antibodies to BOMV, previously detected in bats in West and East Africa, and show that human exposure to BOMV has occurred. Our data suggest human exposure to ebolaviruses may be more frequent and geographically widespread.

5.
J Infect Dis ; 221(Suppl 4): S375-S382, 2020 05 11.
Article in English | MEDLINE | ID: mdl-32034942

ABSTRACT

Bat-borne zoonotic pathogens belonging to the family Paramxyoviridae, including Nipah and Hendra viruses, and the family Filoviridae, including Ebola and Marburg viruses, can cause severe disease and high mortality rates on spillover into human populations. Surveillance efforts for henipaviruses and filoviruses have been largely restricted to the Old World; however, recent studies suggest a potentially broader distribution for henipaviruses and filoviruses than previously recognized. In the current study, we screened for henipaviruses and filoviruses in New World bats collected across 4 locations in Trinidad near the coast of Venezuela. Bat tissue samples were screened using previously established reverse-transcription polymerase chain reaction assays. Serum were screened using a multiplex immunoassay to detect antibodies reactive with the envelope glycoprotein of viruses in the genus Henipavirus and the family Filoviridae. Serum samples were also screened by means of enzyme-linked immunosorbent assay for antibodies reactive with Nipah G and F glycoproteins. Of 84 serum samples, 28 were reactive with ≥1 henipavirus glycoprotein by ≥1 serological method, and 6 serum samples were reactive against ≥1 filovirus glycoproteins. These data provide evidence of potential circulation of viruses related to the henipaviruses and filoviruses in New World bats.


Subject(s)
Chiroptera/virology , Filoviridae Infections/veterinary , Filoviridae , Henipavirus Infections/veterinary , Henipavirus , Animals , Chiroptera/blood , Chiroptera/classification , Filoviridae Infections/epidemiology , Filoviridae Infections/virology , Henipavirus Infections/epidemiology , Henipavirus Infections/virology , Serologic Tests , Trinidad and Tobago/epidemiology
6.
Nat Commun ; 11(1): 510, 2020 01 24.
Article in English | MEDLINE | ID: mdl-31980636

ABSTRACT

Marburg virus (MARV) causes sporadic outbreaks of severe Marburg virus disease (MVD). Most MVD outbreaks originated in East Africa and field studies in East Africa, South Africa, Zambia, and Gabon identified the Egyptian rousette bat (ERB; Rousettus aegyptiacus) as a natural reservoir. However, the largest recorded MVD outbreak with the highest case-fatality ratio happened in 2005 in Angola, where direct spillover from bats was not  shown. Here, collaborative studies by the Centers for Disease Control and Prevention, Njala University, University of California, Davis USAID-PREDICT, and the University of Makeni identify MARV circulating in ERBs in Sierra Leone. PCR, antibody and virus isolation data from 1755 bats of 42 species shows active MARV infection in approximately 2.5% of ERBs. Phylogenetic analysis identifies MARVs that are similar to the Angola strain. These results provide evidence of MARV circulation in West Africa and demonstrate the value of pathogen surveillance to identify previously undetected threats.


Subject(s)
Chiroptera/virology , Marburgvirus/isolation & purification , Africa, Western , Animals , Caves , Genome, Viral , Geography , Likelihood Functions , Marburg Virus Disease/virology , Marburgvirus/classification , Marburgvirus/genetics , Phylogeny , Sequence Analysis, DNA , Viral Proteins/metabolism
7.
Ecohealth ; 17(1): 152-159, 2020 03.
Article in English | MEDLINE | ID: mdl-31811597

ABSTRACT

Bats living in close contact with people in Rwanda were tested for evidence of infection with viruses of zoonotic potential. Mucosal swabs from 503 bats representing 17 species were sampled from 2010 to 2014 and screened by consensus PCR for 11 viral families. Samples were negative for all viral families except coronaviruses, which were detected in 27 bats belonging to eight species. Known coronaviruses detected included the betacorona viruses: Kenya bat coronaviruses, Eidolon bat coronavirus, and Bat coronavirus HKU9, as well as an alphacoronavirus, Chaerephon Bat coronavirus. Novel coronaviruses included two betacorona viruses clustering with SARS-CoV, a 2d coronavirus, and an alphacoronavirus.


Subject(s)
Chiroptera/virology , Coronavirus Infections/veterinary , Coronavirus Infections/virology , Coronavirus/isolation & purification , Animals , Rwanda/epidemiology
8.
Nat Microbiol ; 3(12): 1486, 2018 12.
Article in English | MEDLINE | ID: mdl-30410089

ABSTRACT

In the version of this Article originally published, the bat species for 12 individuals were incorrectly identified in Supplementary Table 1 and 2. After resequencing the MT-CytB and MT-CO1 segments and reviewing the data, the authors have corrected the errors for these 12 animals. In the amended version of the Supplementary Information, Supplementary Tables 1 and 2 have been replaced to include the corrected host species information. None of the 12 bats affected were positive for the Bombali virus, and the conclusions of the study are therefore unchanged.

9.
Nat Microbiol ; 3(10): 1084-1089, 2018 10.
Article in English | MEDLINE | ID: mdl-30150734

ABSTRACT

Here we describe the complete genome of a new ebolavirus, Bombali virus (BOMV) detected in free-tailed bats in Sierra Leone (little free-tailed (Chaerephon pumilus) and Angolan free-tailed (Mops condylurus)). The bats were found roosting inside houses, indicating the potential for human transmission. We show that the viral glycoprotein can mediate entry into human cells. However, further studies are required to investigate whether exposure has actually occurred or if BOMV is pathogenic in humans.


Subject(s)
Chiroptera/virology , Ebolavirus/genetics , Animals , Cell Line, Tumor , Chiroptera/classification , Chiroptera/genetics , Ebolavirus/classification , Genome, Viral/genetics , Humans , Phylogeny , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Viral Load , Virus Internalization
10.
J Mol Biol ; 335(2): 415-24, 2004 Jan 09.
Article in English | MEDLINE | ID: mdl-14672652

ABSTRACT

Reversible phosphorylation of the repetitive C-terminal domain (CTD) of the largest RNA polymerase (RNAP) II subunit plays a key role in the progression of RNAP through the transcription cycle. The level of CTD phosphorylation is determined by multiple CTD kinases and a CTD phosphatase, FCP1. The phosphorylated CTD binds to a variety of proteins including the cis/trans peptidyl-prolyl isomerase (PPIase) Pin1 and enzymes involved in processing of the primary transcript such as the capping enzyme Hce1 and CA150, a nuclear factor implicated in transcription elongation. Results presented here establish that the dephosphorylation of hyperphosphorylated RNAP II (RNAP IIO) by FCP1 is impaired in the presence of Pin1 or Hce1, whereas CA150 has no influence on FCP1 activity. The inhibition of dephosphorylation is observed with free RNAP IIO generated by different CTD kinases as well as with RNAP IIO engaged in an elongation complex. These findings support the idea that specific phospho-CTD associating proteins can differentially modulate the dephosphorylation of RNAP IIO by steric hindrance and may play an important role in the regulation of gene expression.


Subject(s)
Nucleotidyltransferases/metabolism , Peptidylprolyl Isomerase/metabolism , Phosphoprotein Phosphatases/metabolism , RNA Polymerase II/metabolism , Trans-Activators/metabolism , Transcription, Genetic/physiology , Gene Expression Regulation , HeLa Cells , Humans , NIMA-Interacting Peptidylprolyl Isomerase , Phosphorylation/drug effects , Protein Structure, Tertiary , RNA Polymerase II/chemistry , Transcriptional Elongation Factors
11.
J Biol Chem ; 279(9): 7751-9, 2004 Feb 27.
Article in English | MEDLINE | ID: mdl-14672951

ABSTRACT

Elongating RNA polymerase II blocked by DNA damage in the transcribed DNA strand is thought to initiate the transcription-coupled repair process. The objective of this study is to better understand the sequence of events that occurs during repair from the time RNA polymerase II first encounters the lesion. This study establishes that an immobilized DNA template containing a unique cisplatin lesion can serve as an in vitro substrate for both transcription and DNA repair. RNA polymerase II is quantitatively stalled at the cisplatin lesion during transcription and can be released from the template, along with the nascent transcript, in an ATP-dependent manner. RNA polymerase II stalled at a lesion and containing a dephosphorylated repetitive carboxyl-terminal domain (CTD) appears to be more sensitive toward release. However, a dephosphorylated CTD can become readily phosphorylated in front of the lesion by CTD kinases in the presence of ATP. The observation that RNA polymerase II and transcript release occurs in a TFIIH-deficient repair extract but not in a reconstituted repair system demonstrates that disassembly of the elongation complex can occur independently of the repair process and vice versa. Indeed, the presence of RNA polymerase II at the lesion does not prevent dual incision from occurring. Finally, we also propose that the Cockayne's syndrome B protein factor, believed to be the mammalian transcription repair coupling factor, is neither involved in transcript release nor required for dual incision in the presence of lesionstalled RNA polymerase II in vitro. More likely, it prevents RNA polymerase from backing up when it encounters the lesion. The ability to transcribe and repair the same damaged DNA molecule fixed on beads, along with the fact that the reaction conditions can be freely altered, provides a powerful tool to study the fate of RNA polymerase II blocked on the cisplatin lesion.


Subject(s)
Cisplatin/pharmacology , DNA Damage/drug effects , DNA Repair , RNA Polymerase II/metabolism , Adenosine Triphosphate/pharmacology , DNA Helicases/physiology , DNA Repair Enzymes , DNA, Circular/chemistry , DNA, Circular/metabolism , HeLa Cells , Humans , Phosphorylation , Poly-ADP-Ribose Binding Proteins , Protein Kinases/metabolism , RNA/genetics , RNA/metabolism
12.
Chem Rec ; 3(4): 235-45, 2003.
Article in English | MEDLINE | ID: mdl-14595832

ABSTRACT

RNA polymerase (RNAP) II is a complex multisubunit enzyme responsible for the synthesis of mRNA in eukaryotic cells. The largest subunit contains at its C-terminus a unique domain, designated the CTD, comprised of tandem repeats of the consensus sequence Tyr(1)Ser(2)Pro(3)Thr(4)Ser(5)Pro(6)Ser(7). This repeat occurs 52 times in mammalian RNAP II. The CTD is subject to extensive phosphorylation at specific points in the transcription cycle by distinct CTD kinases that phosphorylate certain positions within the consensus repeat. The level and pattern of phosphorylation is determined by the concerted action of CTD kinases and CTD phosphatases. The highly dynamic modification by multiple CTD kinases and phosphatases generate distinct conformations of the CTD that facilitate the recruitment of specific macromolecular assemblies to RNAP II. These CTD interacting proteins influence formation of a preinitiation complex at the promoter and couple processing of the primary transcript to the elongation complex.


Subject(s)
RNA Polymerase II/physiology , Transcription, Genetic/physiology , Phosphorylation , Protein Conformation , RNA Polymerase II/chemistry
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