Detection and serotyping of foot-and-mouth disease virus with laboratory and in silico methods

Foot-and-mouth disease virus (FMDV) is a highly contagious animal pathogen and it has a variable genome and high antigenic variation. There are seven known serotypes of this virus: A, O, C, Asia1, SAT1, SAT2, and SAT3. The rapid detection and serotype characterization of the virus is instrumental for the prompt response by animal health authorities. This thesis presents the design and development of the first electronic microarray assay for the simultaneous detection and subtyping of FMDV. The assay was evaluated in silico and it was tested with 19 synthetic DNA constructs representing all 7 serotypes, followed by the testing with 23 viral RNA samples representing all 7 serotypes. Also, various in silico methods were compared for the classification of FMDV sequences using complete genomes and next generation sequencing (NGS) data. Finally, highly specific and highly sensitive single nucleotide variant signatures that distinguish the seven FMDV serotypes were discovered.Chemical, Biological, Radiological-Nuclear, and Explosives Research and Technology Initiative (CRTI) Project 09-403T

The pangenome of the wheat pathogen <i>Pyrenophora tritici-repentis</i> reveals novel transposons associated with necrotrophic effectors <i>ToxA</i> and <i>ToxB</i>

BACKGROUND: In fungal plant pathogens, genome rearrangements followed by selection pressure for adaptive traits have facilitated the co-evolutionary arms race between hosts and their pathogens. Pyrenophora tritici-repentis (Ptr) has emerged recently as a foliar pathogen of wheat worldwide and its populations consist of isolates that vary in their ability to produce combinations of different necrotrophic effectors. These effectors play vital roles in disease development. Here, we sequenced the genomes of a global collection (40 isolates) of Ptr to gain insights into its gene content and genome rearrangements. RESULTS: A comparative genome analysis revealed an open pangenome, with an abundance of accessory genes (~ 57%) reflecting Ptr’s adaptability. A clear distinction between pathogenic and non-pathogenic genomes was observed in size, gene content, and phylogenetic relatedness. Chromosomal rearrangements and structural organization, specifically around effector coding genes, were detailed using long-read assemblies (PacBio RS II) generated in this work in addition to previously assembled genomes. We also discovered the involvement of large mobile elements associated with Ptr’s effectors: ToxA, the gene encoding for the necrosis effector, was found as a single copy within a 143-kb ‘Starship’ transposon (dubbed ‘Horizon’) with a clearly defined target site and target site duplications. ‘Horizon’ was located on different chromosomes in different isolates, indicating mobility, and the previously described ToxhAT transposon (responsible for horizontal transfer of ToxA) was nested within this newly identified Starship. Additionally, ToxB, the gene encoding the chlorosis effector, was clustered as three copies on a 294-kb element, which is likely a different putative ‘Starship’ (dubbed ‘Icarus’) in a ToxB-producing isolate. ToxB and its putative transposon were missing from the ToxB non-coding reference isolate, but the homolog toxb and ‘Icarus’ were both present in a different non-coding isolate. This suggests that ToxB may have been mobile at some point during the evolution of the Ptr genome which is contradictory to the current assumption of ToxB vertical inheritance. Finally, the genome architecture of Ptr was defined as ‘one-compartment’ based on calculated gene distances and evolutionary rates. CONCLUSIONS: These findings together reflect on the highly plastic nature of the Ptr genome which has likely helped to drive its worldwide adaptation and has illuminated the involvement of giant transposons in facilitating the evolution of virulence in Ptr. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12915-022-01433-w

Biogeography and genotypic diversity of Metarhizium brunneum and Metarhizium robertsii in northwestern North American soils

The biogeography and genotype diversity of Metarhizium species in northwestern North American soils was examined; twenty ecoregions were sampled, including 58 agricultural and 80 natural habitat subsites, and areas that were glaciated during the Pleistocene epoch. One hundred and twenty nine isolates of M. brunneum, 26 isolates of M. robertsii, four isolates of M. guizhouense, one isolate of M. flavoviride, and 55 isolates of Beauveria were recovered. Metarhizium and Beauveria species were isolated in diverse ecoregions within the study area, but a trend for increased isolation of Metarhizium species in western regions of the study area was observed. Consistent with this observation, the prevalence of M. brunneum and M. robertsii decreased at higher elevations, and the opposite was true for Beauveria. Both M. brunneum and M. robertsii were more commonly isolated from agricultural and natural habitat subsites, and considerable genotypic diversity was observed in both habitats and within the same subsite. Metarhizium robertsii but not M. brunneum was more commonly isolated from non-glaciated locations; however, less diversity and richness was observed for M. brunneum recovered from glaciated versus non-glaciated locations consistent with insular biogeography. The study has implications for microbial control strategies in the region.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Characterization of the hoof bacterial communities in feedlot cattle affected with digital dermatitis, foot rot or both using a surface swab technique

Abstract Background Lameness is defined as altered or abnormal gait due to dysfunction of the locomotor system, and is a health issue of feedlot cattle, having major economic, labour, and welfare implications. Digital dermatitis (DD—a lesion of the plantar surface of the foot) and foot rot (FR—affects the interdigital cleft) are common infectious causes of lameness in feedlots. These hoof lesions can occur alone or in combination (DD + FR) in the same hoof. A total of 208 hoof swabs were collected from three commercial feedlots located in southern Alberta. Every lesion sample was matched with a corresponding control skin sample taken from a healthy contralateral foot. Control skin samples were also collected from cattle with no lesion on any feet. Bacterial communities of three types of hoof lesions (DD, DD + FR, FR) and healthy skin were profiled using 16S amplicon sequencing. Results Alpha diversity analysis revealed a lower bacterial diversity on DD and FR lesions compared to control skin. Beta diversity analysis showed that bacterial communities of DD, FR, and DD + FR lesions were distinct from those of the control skin. While the impact of feedlot was minimal, lesion type contributed to 22% of the variation observed among bacterial communities (PERMANOVA-R = 0.22, P < 0.01). Compared to the corresponding control skin, there were 11, 12, and 3 differentially abundant (DA) bacterial genera in DD, DD + FR, and FR lesions, respectively. Conclusions The bacterial community description of a DD + FR lesion is a novel finding. Not only did lesions lead to altered bacterial communities when compared to healthy skin, but the composition of those communities also differed depending on the hoof lesion. The 16S amplicon sequencing of surface swabs has significant value as a research tool in separating different hoof lesions and can provide additional insights to the polybacterial etiology of DD and FR in feedlot cattle

Elucidation of Physiological, Transcriptomic and Metabolomic Salinity Response Mechanisms in Medicago sativa

Alfalfa (Medicago sativa L.) is a widely grown perennial leguminous forage crop with a number of positive attributes. However, despite its moderate ability to tolerate saline soils, which are increasing in prevalence worldwide, it suffers considerable yield declines under these growth conditions. While a general framework of the cascade of events involved in plant salinity response has been unraveled in recent years, many gaps remain in our understanding of the precise molecular mechanisms involved in this process, particularly in non-model yet economically important species such as alfalfa. Therefore, as a means of further elucidating salinity response mechanisms in this species, we carried out in-depth physiological assessments of M. sativa cv. Beaver, as well as transcriptomic and untargeted metabolomic evaluations of leaf tissues, following extended exposure to salinity (grown for 3–4 weeks under saline treatment) and control conditions. In addition to the substantial growth and photosynthetic reductions observed under salinity treatment, we identified 1233 significant differentially expressed genes between growth conditions, as well as 60 annotated differentially accumulated metabolites. Taken together, our results suggest that changes to cell membranes and walls, cuticular and/or epicuticular waxes, osmoprotectant levels, antioxidant-related metabolic pathways, and the expression of genes encoding ion transporters, protective proteins, and transcription factors are likely involved in alfalfa’s salinity response process. Although some of these alterations may contribute to alfalfa’s modest salinity resilience, it is feasible that several may be disadvantageous in this context and could therefore provide valuable targets for the further improvement of tolerance to this stress in the future.Science, Faculty ofNon UBCChemistry, Department ofReviewedFacultyResearcherGraduat

Identification of Differential Drought Response Mechanisms in Medicago sativa subsp. sativa and falcata through Comparative Assessments at the Physiological, Biochemical, and Transcriptional Levels

Alfalfa (Medicago sativa L.) is an extensively grown perennial forage legume, and although it is relatively drought tolerant, it consumes high amounts of water and depends upon irrigation in many regions. Given the progressive decline in water available for irrigation, as well as an escalation in climate change-related droughts, there is a critical need to develop alfalfa cultivars with improved drought resilience. M. sativa subsp. falcata is a close relative of the predominantly cultivated M. sativa subsp. sativa, and certain accessions have been demonstrated to exhibit superior performance under drought. As such, we endeavoured to carry out comparative physiological, biochemical, and transcriptomic evaluations of an as of yet unstudied drought-tolerant M. sativa subsp. falcata accession (PI 641381) and a relatively drought-susceptible M. sativa subsp. sativa cultivar (Beaver) to increase our understanding of the molecular mechanisms behind the enhanced ability of falcata to withstand water deficiency. Our findings indicate that unlike the small number of falcata genotypes assessed previously, falcata PI 641381 may exploit smaller, thicker leaves, as well as an increase in the baseline transcriptional levels of genes encoding particular transcription factors, protective proteins, and enzymes involved in the biosynthesis of stress-related compounds. These findings imply that different falcata accessions/genotypes may employ distinct drought response mechanisms, and the study provides a suite of candidate genes to facilitate the breeding of alfalfa with enhanced drought resilience in the future

Prairie Agroecosystems: Interconnected Microbiomes of Livestock, Soil and Insects

Agroecosystems are comprised of environmental compartments where associated microbial communities interact with one another. These microbial communities, called microbiomes, inhabit livestock, insects, and plants. Microbiomes are also present in the soil and watersheds. Clarifying the nature and extent of microbial interactions between compartments both at intra-farm and global scales can promote sustainable production systems, healthier animals, increased crop yields, and safer meat products. Early research on microbiomes was hindered by a lack of expertise and the high cost of molecular sequencing. However, these limitations have been largely resolved with advances in and reduced costs of sequencing technologies. In this paper, we summarize sequencing and bioinformatics approaches, and review the crucial roles of diverse microbiomes in livestock, plants and soil, as well as pollinators and pest insects. These crucial roles include nutrient cycling, nutrient acquisition, metabolism of toxins and enhanced host immune function. Additionally, we examine potentially undesirable effects of microbiomes associated with climate change and agri-food production such as their role in the release of greenhouse gases from cattle and their impact on meat safety and spoilage. By increasing the awareness of microbiomes and the growing ease with which they can be studied, we hope to foster a greater adoption of microbiome research. Further understanding of the diverse effects and interactions of microbiomes will advance our efforts to increase agricultural production while reducing its negative environmental footprint, thus making the agroecosystems more sustainable

Prairie Agroecosystems: Interconnected Microbiomes of Livestock, Soil and Insects

Agroecosystems are comprised of environmental compartments where associated microbial communities interact with one another. These microbial communities, called microbiomes, inhabit livestock, insects, and plants. Microbiomes are also present in the soil and watersheds. Clarifying the nature and extent of microbial interactions between compartments both at intra-farm and global scales can promote sustainable production systems, healthier animals, increased crop yields, and safer meat products. Early research on microbiomes was hindered by a lack of expertise and the high cost of molecular sequencing. However, these limitations have been largely resolved with advances in and reduced costs of sequencing technologies. In this paper, we summarize sequencing and bioinformatics approaches, and review the crucial roles of diverse microbiomes in livestock, plants and soil, as well as pollinators and pest insects. These crucial roles include nutrient cycling, nutrient acquisition, metabolism of toxins and enhanced host immune function. Additionally, we examine potentially undesirable effects of microbiomes associated with climate change and agri-food production such as their role in the release of greenhouse gases from cattle and their impact on meat safety and spoilage. By increasing the awareness of microbiomes and the growing ease with which they can be studied, we hope to foster a greater adoption of microbiome research. Further understanding of the diverse effects and interactions of microbiomes will advance our efforts to increase agricultural production while reducing its negative environmental footprint, thus making the agroecosystems more sustainable

Iron accumulation drives fibrosis, senescence and the senescence-associated secretory phenotype.

Fibrogenesis is part of a normal protective response to tissue injury that can become irreversible and progressive, leading to fatal diseases. Senescent cells are a main driver of fibrotic diseases through their secretome, known as senescence-associated secretory phenotype (SASP). Here, we report that cellular senescence, and multiple types of fibrotic diseases in mice and humans are characterized by the accumulation of iron. We show that vascular and hemolytic injuries are efficient in triggering iron accumulation, which in turn can cause senescence and promote fibrosis. Notably, we find that senescent cells persistently accumulate iron, even when the surge of extracellular iron has subdued. Indeed, under normal conditions of extracellular iron, cells exposed to different types of senescence-inducing insults accumulate abundant ferritin-bound iron, mostly within lysosomes, and present high levels of labile iron, which fuels the generation of reactive oxygen species and the SASP. Finally, we demonstrate that detection of iron by magnetic resonance imaging might allow non-invasive assessment of fibrotic burden in the kidneys of mice and in patients with renal fibrosis. Our findings suggest that iron accumulation plays a central role in senescence and fibrosis, even when the initiating events may be independent of iron, and identify iron metabolism as a potential therapeutic target for senescence-associated diseases.Acknowledgements: We are grateful to K. Raj (Altos Laboratories) for his help with the experiments on replicative senescence. We thank D. Muñoz Espin (University of Cambridge) for sending us the IMR90 cells stably transduced with tamoxifen inducible Ras-G12V. We thank R. Mendez (IRB) for the H5V and HUVEC cells. We thank staf at the TEM-SEM Electron Microscopy Unit from Scientific and Technological Centers (CCiTUB), Universitat de Barcelona for their support and advice on TEM techniques. We are thankful to the Magnetic Resonance Imaging Core Facility of the Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) for the scientific and technical support in MRI acquisition and analysis. M.M. received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement (no. 794744) and from the Spanish Ministry of Science and Innovation (MCIN) (RYC2020-030652-I/AEI/10.13039/501100011033). V.L.P. was a recipient of a predoctoral contract from the Spanish Ministry of Education (FPU-18/05917). K.M. was a recipient of fellowships from the German Cardiac, the German Research Foundation and a postdoctoral contract Juan de la Cierva from the MCIN. F.H.G. was supported by the PhD4MD Collaborative Research Training Program for Medical Doctors (IRB Barcelona/Hospital Clinic/IDIBAPS). M. Sanchez was funded by grants PID2021- 122436OB-I00 from MCIN/AEI/10.13039/501100011033/FEDER, UE, RETOS COLABORACION RTC2019-007074-1 from MCIN/ AEI/10.13039/501100011033. C.L.-M. was a recipient of a predoctoral contract from the Spanish Ministry of Education (FPU-18/02965). G.A. was funded by the Instituto de Salud Carlos III through project PI 20/01360, FEDER funds. J.M.C. was funded by the Instituto de Salud Carlos III through projects PI18/00910 and PI21/00931 (co-funded by European Regional Development Fund, a way to build Europe) and thanks the CERCA Programme/ Generalitat de Catalunya for institutional support. Work in the laboratory of M. Serrano was funded by the IRB and ‘laCaixa’ Foundation and by grants from the Spanish Ministry of Science co-funded by the European Regional Development Fund (SAF2017- 82613-R), European Research Council (ERC-2014-AdG/669622) and grant RETOS COLABORACION RTC2019-007125-1 from MCIN/AEI and Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement of Catalonia (Grup de Recerca consolidat 2017 SGR 282