32 research outputs found

    Mapping the proteins of the herpes simplex virus type 1 capsid

    Get PDF
    The aims of the work presented in this thesis were to use a variety of mutagenesis techniques to investigate the proteins of the HSV-1 capsid. Triplexes are heterotrimers formed by two proteins in a 1:2 stoichiometry. The single-copy protein is called VP19C, and the dimeric protein is VP23. Insertional and deletional mutagenesis was carried out on VP19C and the effects of the mutations on virus growth and capsid assembly were examined. Insertional mutagenesis showed that VP19C can be divided into three regions with respect to their ability to tolerate five amino acid insertions, with two regions of approximately 100 amino acids at the N- and C-terminal regions of the protein being more tolerant of such insertions than a ~350 amino acid central region. The N-terminal ~100 amino acids of the protein, which are particularly insensitive to insertional mutagenesis, correspond to a region that is poorly conserved among herpesviruses. Some, but not all, severely disabled mutants were compromised in their ability to bind VP23 and VP5. Analysis of deletional mutants revealed the presence of an unusual nuclear localisation signal (NLS) near the N-terminus of VP19C. This was mapped to a 33 amino acid region by fusion of specific sequences to a green fluorescent protein (GFP) marker. By replacing the endogenous NLS with that from the simian virus 40 (SV40) large T antigen, we were able to show that the first 45 amino acids of VP19C were not essential for assembly of functional capsids and infectious virus particles. However, removing the first 63 amino acids resulted in the formation of aberrant capsids and prevented virus growth, suggesting that the poorly-conserved N-terminal sequences have some as-yet-unidentified function

    The Sneeuberg: A new centre of floristic endemism on the Great Escarpment, South Africa

    Get PDF
    The Sneeuberg mountain complex (Eastern Cape) comprises one of the most prominent sections of the Great Escarpment in southern Africa but until now has remained one of the botanically least known regions. The Sneeuberg is a discrete orographical entity, being delimited in the east by the Great Fish River valley, in the west by the Nelspoort Interval, to the south by the Plains of Camdeboo, and to the north by the Great Karoo pediplain. The highest peaks range from 2278 to 2504 m above sea level, and the summit plateaux range from 1800 to 2100 m. Following extensive literature review and a detailed collecting programme, the Sneeuberg is reported here as having a total flora of 1195 species of which 107 (9%) are alien species, 33 (2.8%) are endemic, and 13 (1.1%) near-endemic. Five species previously reported as Drakensberg Alpine Centre (DAC) endemics are now known to occur in the Sneeuberg (representing range extensions of some 300–500 km). One-hundred-and-five species (8.8%) are DAC near-endemics, with the Sneeuberg being the western limit for most of these. Ten species (0.8%) represent disjunctions across the Karoo Interval from the Cape Floristic Region (CFR) to the Sneeuberg. In all, some 23 significant range extensions, eight new species, and several rediscoveries are recorded. We conclude by recognising the Sneeuberg as a new centre of endemism along the Great Escarpment, with floristic affinities with the Albany Centre and the DAC, and links to the CFR

    Distemper, extinction, and vaccination of the Amur tiger

    Get PDF
    Canine distemper virus (CDV) has recently emerged as an extinction threat for the endangered Amur tiger (Panthera tigris altaica). CDV is vaccine-preventable, and control strategies could require vaccination of domestic dogs and/or wildlife populations. However, vaccination of endangered wildlife remains controversial, which has led to a focus on interventions in domestic dogs, often assumed to be the source of infection. Effective decision making requires an understanding of the true reservoir dynamics, which poses substantial challenges in remote areas with diverse host communities. We carried out serological, demographic, and phylogenetic studies of dog and wildlife populations in the Russian Far East to show that a number of wildlife species are more important than dogs, both in maintaining CDV and as sources of infection for tigers. Critically, therefore, because CDV circulates among multiple wildlife sources, dog vaccination alone would not be effective at protecting tigers. We show, however, that low-coverage vaccination of tigers themselves is feasible and would produce substantive reductions in extinction risks. Vaccination of endangered wildlife provides a valuable component of conservation strategies for endangered species

    AFRIDATA: a COVID-19 dashboard for Africa

    No full text
    AFRIDATA is a project created by a team of students at the University of Glasgow in collaboration with Walt Adamson. Through various data visualisations, we hope to inform the public about the COVID-19 pandemic in Africa

    Mutational Analysis of the Herpes Simplex Virus Triplex Protein VP19C

    No full text
    Herpes simplex virus type 1 (HSV-1) capsids have an icosahedral structure with capsomers formed by the major capsid protein, VP5, linked in groups of three by distinctive structures called triplexes. Triplexes are heterotrimers formed by two proteins in a 1:2 stoichiometry. The single-copy protein is called VP19C, and the dimeric protein is VP23. We have carried out insertional and deletional mutagenesis on VP19C and have examined the effects of the mutations on virus growth and capsid assembly. Insertional mutagenesis showed that the N-terminal ∼100 amino acids of the protein, which correspond to a region that is poorly conserved among herpesviruses, are insensitive to disruption and that insertions into the rest of the protein had various effects on virus growth. Some, but not all, severely disabled mutants were compromised in the ability to bind VP23 or VP5. Analysis of deletion mutants revealed the presence of a nuclear localization signal (NLS) near the N terminus of VP19C, and this was mapped to a 33-amino-acid region by fusion of specific sequences to a green fluorescent protein marker. By replacing the endogenous NLS with that from the simian virus 40 large T antigen, we were able to show that the first 45 amino acids of VP19C were not essential for assembly of functional capsids and infectious virus particles. However, removing the first 63 amino acids resulted in formation of aberrant capsids and prevented virus growth, suggesting that the poorly conserved N-terminal sequences have some as-yet-unidentified function

    Parasite Street Science

    No full text
    In 2019, Professor Annette MacLeod's Group along with colleagues from the School of Life Sciences began working with Surge, a Scotland-based organisation that develops street arts, circus and physical theatre. The aim of this collaboration is to explore the use of street theatre in engaging new audiences with our research. In this case, the MacLeod Group's work on African sleeping sickness. Members of the Macleod Group and undergraduate and postgraduate students from the School of Life Sciences worked with theatre professionals from Surge to create a performance that was premiered at the Merchant City Festival / Surge Festival in Glasgow in July 2021. Surge have spent some time in the lab with the Macleod Group, and researchers have taken part in several creative workshops to develop the piece. Early in 2020, the collaboration received a grant from the Microbiology Society to support the project

    SARS-CoV-2 seroprevalence at urban and rural sites in Kaduna State, Nigeria, during October/November 2021, immediately prior to detection of the Omicron variant

    Get PDF
    Background: Nigeria is Africa’s most populated country. By November 2021 it had experienced three waves of SARS-CoV-2 infection. Peer-reviewed seroprevalence data assessing the proportion of the Nigerian population that have been infected were extremely limited. Methods: We conducted a serosurvey in one urban site (n = 400) and one rural site (n = 402) in Kaduna State, Nigeria between 11 October 2021 and 8 November 2021. Z-tests were used to compare seroprevalence across age groups, locations and sexes. T tests were used to determine whether age or household size are associated with seropositivity. Associations between seropositivity and recent history of common Covid-19 symptoms were tested using logistic regression. Results: SARS-CoV-2 antibodies were detected in 42.5% an 53.5% of participants at the urban and rural sites, respectively The overall age- and sex- stratified seroprevalence was 43.7% (42.2% for unvaccinated individuals). The data indicate an infection rate in Kaduna State ≥359-fold the rate derived from polymerase chain reaction-confirmed cases. In the urban site, seroprevalence among females and participants aged <20 was lower than other groups. Reporting loss of sense of taste and/or smell was strongly associated with seropositive status. Associations with seropositivity were also found for the reporting of dry cough, fever, headache, nausea and sore throat. Conclusions: This study provides baseline SARS-CoV-2 seroprevalence in Kaduna State, Nigeria, immediately prior to the spread of the Omicron variant. It indicates that in October/November 2021, approximately 56% of the population did not have detectable antibodies, and population subgroups with particularly low seroprevalence remain. It highlights limitations in using PCR-confirmed cases to estimate infection rates. The data will inform public health strategies in Nigeria and other sub-Saharan African countries with limited SARS-CoV-2 seroprevalence data

    Longevity and determinants of protective humoral immunity after pandemic influenza infection

    No full text
    Rationale: Antibodies to influenza hemagglutinin are the primary correlate of protection against infection. The strength and persistence of this immune response influences viral evolution and consequently the nature of influenza epidemics. However, the durability and immune determinants of induction of humoral immunity after primary influenza infection remain unclear. Objectives: The spread of a novel H1N1 (A[H1N1]pdm09) virus in 2009 through an unexposed population offered a natural experiment to assess the nature and longevity of humoral immunity after a single primary influenza infection. Methods: We followed A(H1N1)pdm09-seronegative adults through two influenza seasons (2009–2011) as they developed A(H1N1)pdm09 influenza infection or were vaccinated. Antibodies to A(H1N1)pdm09 virus were measured by hemagglutination-inhibition assay in individuals with paired serum samples collected preinfection and postinfection or vaccination to assess durability of humoral immunity. Preexisting A(H1N1)pdm09-specific multicytokine-secreting CD4 and CD8 T cells were quantified by multiparameter flow cytometry to test the hypothesis that higher frequencies of CD4+ T-cell responses predict stronger antibody induction after infection or vaccination. Measurements and Main Results: Antibodies induced by natural infection persisted at constant high titer for a minimum of approximately 15 months. Contrary to our initial hypothesis, the fold increase in A(H1N1)pdm09-specific antibody titer after infection was inversely correlated to the frequency of preexisting circulating A(H1N1)pdm09-specific CD4+IL-2+IFN-γ−TNF-α− T cells (r = −0.4122; P = 0.03). Conclusions: The longevity of protective humoral immunity after influenza infection has important implications for influenza transmission dynamics and vaccination policy, and identification of its predictive cellular immune correlate could guide vaccine development and evaluation

    Формирование иноязычной коммуникативной компетенции при обучении чтению

    Get PDF
    We conducted a longitudinal community cohort study of healthy adults in the UK. We found significantly higher incidence of influenza A(H1N1)pdm09 infection in 2010–11 than in 2009–10, a substantial proportion of subclinical infection, and higher risk for infection during 2010–11 among persons with lower preinfection antibody titers
    corecore