Latest Publications
Phenotypic and genotypic characterization of fifty strains of Beauveria spp. (Ascomycota, Cordycipitaceae) fungal entomopathogens from diverse geographic origins against the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)
Laura Reyes-Haro, Gillian Prince, Rommel Santiago Granja-Travez, David Chandler
The diamondback moth (DBM) (Plutella xylostella) causes large losses to global crop production. Conventional insecticides are losing effectiveness due to resistance. Consequently, there is a growing interest in sustainable control methods like entomopathogenic fungi (EPF) in Integrated Pest Management. However, the field efficacy of fungi varies due to environmental influences. In this study, a group of 50 Beauveria strains sourced from different locations were characterized by genotype and phenotype with respect to their conidial production, temperature and UV-B radiation tolerance, and virulence against DBM. Survival under environmental conditions is crucial for EPF-based commercial products against DBM. Results suggest strain tolerance to environmental stressors is more tied to specific micro-climatic factors than geographical origin. Each strain exhibited unique characteristics; for example, the most virulent strain (#29) was highly UV-sensitive. Therefore, characterizing diverse strains provides essential genotypic and phenotypic insights, which are fundamental for understanding their role as biocontrol agents while facilitating efficient biopesticide product development and uptake
Structures of wild-type and a constitutively closed mutant of connexin26 shed light on channel regulation by CO2
Deborah H. Brotherton, Sarbjit Nijjar, Christos G. Savva, Nicholas Dale, Alexander D. Cameron
Connexins allow intercellular communication by forming gap junction channels (GJCs) between juxtaposed cells. Connexin26 (Cx26) can be regulated directly by CO2. This is proposed to be mediated through carbamylation of K125. We show that mutating K125 to glutamate, mimicking the negative charge of carbamylation, causes Cx26 GJCs to be constitutively closed. Through cryo-EM we observe that the K125E mutation pushes a conformational equilibrium towards the channel having a constricted pore entrance, similar to effects seen on raising the partial pressure of CO2. In previous structures of connexins, the cytoplasmic loop, important in regulation and where K125 is located, is disordered. Through further cryo-EM studies we trap distinct states of Cx26 and observe density for the cytoplasmic loop. The interplay between the position of this loop, the conformations of the transmembrane helices and the position of the N-terminal helix, which controls the aperture to the pore, provides a mechanism for regulation.
Combining models to generate consensus medium-term projections of hospital admissions, occupancy and deaths relating to COVID-19 in England
Harrison Manley,Thomas Bayley,Gabriel Danelian, Lucy Burton, Thomas Finnie, Andre Charlett, Nicholas A. Watkins, Paul Birrell, Daniela De Angelis, Matt Keeling, Sebastian Funk, Graham Medley, Lorenzo Pellis, Marc Baguelin, Graeme J. Ackland, Johanna Hutchinson, Steven Riley and Jasmina Panovska-Griffiths
Mathematical modelling has played an important role in offering informed advice during the COVID-19 pandemic. In England, a cross government and academia collaboration generated medium-term projections (MTPs) of possible epidemic trajectories over the future 4–6 weeks from a collection of epidemiological models. In this article, we outline this collaborative modelling approach and evaluate the accuracy of the combined and individual model projections against the data over the period Learning from our experience of ensemble modelling during the COVID-19 epidemic, our findings highlight the importance of developing cross-institutional multi-model infectious disease hubs for future outbreak control.
Mitochondrial and microbial diversity of the invasive mosquito vector species Culex tritaeniorhynchus across its extensive inter-continental geographic range
Claire L. Jeffries, Luciano M Tantely, Perparim Kadriaj, Marcus S C Blagrove, Ioanna Lytra, James Orsborne, Hasan Mohammad Al-Amin, Abdul Rahim Mohammed, Mohammad Shafiul Alam, Romain Girod, Yaw A Afrane, Silvia Bino, Vincent Robert, Sebastien Boyer, Matthew Baylis, Enkelejda Velo, Grant L Hughes, Thomas Walker
In this study, we used laboratory vector competence experiments to determine if Cx. tritaeniorhynchus from a Southern European population were competent JEV vectors. We obtained samples from multiple geographically dispersed Cx. tritaeniorhynchus populations from countries within Europe, Africa, Eurasia and Asia to perform phylogenetic analysis to measure the level of mitochondrial divergence using the cytochrome oxidase subunit 1 (CO1) gene. We also undertook bacterial 16S rRNA gene amplicon sequencing to determine microbial diversity and used multi-locus sequence typing (MLST) to determine any evidence for the presence of strains of the naturally occurring endosymbiotic bacterium Wolbachia. Cx. tritaeniorhynchus from a Greek population were shown be be competent vectors of JEV with high levels of virus present in saliva. We found a signficant level of mitochondrial genetic diversity using the mosquito CO1 gene between geographically dispersed populations. Furthermore, we report diverse microbiomes identified by 16S rRNA gene amplicon sequencing within and between geographical populations. Evidence for the detection of the endosymbiotic bacteria Wolbachia was confirmed using Wolbachia-specific PCR and MLST.
Response patterns of the microbiome during hexavalent chromium remediation by Tagetes erecta L
Juanjuan Xiao, Deying Wang, Banerjee Sinchan, Ryan Mushinski, Decai Jin, Ye Deng
Chromium pollution, particularly hexavalent chromium [Cr(VI)], may threaten the environment and human health. This study investigated the potential of Tagetes erecta L. (Aztec marigold) for phytoremediation of soil contaminated with Cr(VI), and focused on the effects of varying concentrations of Cr(VI) on both the physicochemical properties of soil and microbiome of Tagetes erecta L. We observed that Tagetes erecta L. showed tolerance to Cr(VI) stress and maintained normal growth under these conditions, as indicated by bioconcentration factors of 0.33–0.53 in shoots and 0.39–0.70 in roots. Meanwhile, the structure and diversity of bacterial communities were significantly affected by Cr(VI) pollution. This study explored the interactions between heavy metals, microorganisms, and plants, providing valuable insights for developing in situ bioremediation of Cr(VI)-contaminated soils.
Membraneless channels sieve cations in ammonia-oxidizing marine archaea
Andriko von Kügelgen, C. Keith Cassidy, Sofie van Dorst, Lennart L. Pagani, Christopher Batters, Zephyr Ford, Jan Löwe, Vikram Alva, Phillip J. Stansfeld & Tanmay A. M. Bharat
Nitrosopumilus maritimus is an ammonia-oxidizing archaeon that is crucial to the global nitrogen cycle. A critical step for nitrogen oxidation is the entrapment of ammonium ions from a dilute marine environment at the cell surface and their subsequent channelling to the cell membrane of N. maritimus. Here we elucidate the structure of the molecular machinery responsible for this process, comprising the surface layer (S-layer), using electron cryotomography and subtomogram averaging from cells. We supplemented our in situ structure of the ammonium-binding S-layer array with a single-particle electron cryomicroscopy structure, revealing detailed features of this immunoglobulin-rich and glycan-decorated S-layer. This in situ structural study illuminates the biogeochemically essential process of ammonium binding and channelling, common to many marine microorganisms that are fundamental to the nitrogen cycle.