Branko Rihtman, Alberto Torcello-Requena, Alvetina Mikhaylina, Richard J Puxty, Martha RJ Clokie, Andrew D Millard, David J Scanlan

Phosphorus (P) is a major abiotic control on the marine cyanobacterium Synechococcus. Some viruses infecting Synechococcus have acquired, from their host, a gene encoding a P substrate binding protein (PstS), thought to improve virus replication under phosphate starvation. Yet, pstS is uncommon amongst cyanobacterial viruses. Thus, we asked how infections with viruses lacking PstS are affected by P scarcity. We show that production of infectious virus particles of such viruses is reduced in low P conditions. Our data shows how phage genomes, lacking obvious P-stress related genes, have evolved to exploit their host’s environmental sensing mechanisms to coordinate their own gene expression in response to resource limitation.

ISME Journal. March 2024

Anita Ramesh, Paula Oliveira, Mary Cameron, Priscila M S Castanha, Thomas Walker, Audrey Lenhart, Lucy Impoinvil, Neal Alexander, Zulma Medeiros, André Sá, Abraham Rocha, Wayner V Souza, Amélia Maciel, Cynthia Braga

Lymphatic filariasis (LF) is a leading cause of disability due to infectious disease worldwide. The Recife Metropolitan Region (RMR) is the only remaining focus of LF in Brazil, where the parasite Wuchereria bancrofti is transmitted solely by the mosquito Culex quinquefasciatus. This study reports the results of transmission assessment surveys and molecular xenomonitoring in the city of Olinda, RMR, after nearly 15 years (2015-2016) of interventions for LF elimination. Participants were screened for W. bancrofti antigen via immunochromatographic card tests (ICT), and all 1,170 children from MDA areas and the entire population sample of 990 residents in non-MDA areas were ICT negative. In MDA areas, a total of 3,152 female Cx. quinquefasciatus mosquitoes in 277 households were collected via aspiration. RT-qPCR of 233 pools of mosquitos were negative for W. bancrofti RNA; an independent reference laboratory confirmed these results. These results provide evidence that LF transmission has been halted in this setting.

American Journal of Tropical Medicine & Hygiene. March 2024

Brooks S, Weaver JA, Klomchit A, Alharthi SA, Onlamun T, Nurani R, Vong TK, Alberti F and Greco C

Endophytic fungi constitute a rich source of secondary metabolites that can be manipulated to produce desirable novel analogs for combating current agricultural challenges for crop production, especially controlling plant disease. The endophytic fungus Daldinia eschscholtzii MFLUCC 19-0629, was newly isolated from tropical ancient plants, Oncosperma sp., and displays a broad-spectrum of antifungal and antibacterial activities against several plant pathogens. The discovery that D. eschscholtzii MFLUCC 19-0629 has a broad spectrum of antimicrobial activity against seven major plant pathogenic microorganisms relevant to crop production and its complete genome sequence carries immense importance in the advancement of novel microbial biocontrol agents (MBCAs). This also unveils the prospect of uncovering new compounds that could be utilized for sustainable agriculture and pharmaceutical purposes.

Frontiers in Chemical Biology. March 2024

Talal Al-Yazeedi, Sally Adams, Sophie Tandonnet, Anisa Turner, Jun Kim, Junho Lee, Andre Pires-daSilva

Auanema freiburgense is a nematode with males, females, and selfing hermaphrodites. When XO males mate with XX females, they typically produce a low proportion of XO offspring because they eliminate nullo-X spermatids. This occurs because of an unequal distribution of essential cellular organelles during sperm formation. Intriguingly, the interbreeding of two A. freiburgense strains results in hybrid males capable of producing viable nullo-X sperm. Consequently, when these hybrid males mate with females, they yield a high percentage of male offspring. To uncover the genetic basis of nullo-spermatid elimination and X- chromosome drive, we generated a genome assembly for A. freiburgense, and genotyped the intercrossed lines. This analysis identified a Quantitative Trait Locus spanning several X chromosome genes linked to the non-Mendelian inheritance patterns observed in A. freiburgense. This finding provides valuable clues to the underlying factors involved in asymmetric organelle partitioning during male meiotic division and thus non-Mendelian transmission of the X chromosome and sex ratios.

Genetics. March 2024

Ryan Cook​, Nathan Brown​, Branko Rihtman​, Slawomir Michniewski​, Tamsin Redgwell, Martha Clokie​, Dov J. Stekel, Yin Chen​, David J. Scanlan​, Jon L. Hobman, Andrew Nelson​, Michael A. Jones​, Darren Smith​ and Andrew Millard

ecology. Long-read sequencing and hybrid assembly approaches that combine long- and short-read technologies are now being widely implemented in bacterial genomics and metagenomics. However, the use of long-read sequencing to investigate viral communities is still in its infancy. While Nanopore and PacBio technologies have been applied to viral metagenomics, it is not known to what extent different technologies will impact the reconstruction of the viral community. Thus, we constructed a mock bacteriophage community of previously sequenced phage genomes and sequenced them using Illumina, Nanopore and PacBio sequencing technologies and tested a number of different assembly approaches. Overall the best approach was assembly by a combination of Illumina and Nanopore reads, which reduced error rates to levels comparable with short-read-only assemblies. When using a single technology, Illumina only was the best approach. These findings will provide a starting point for others in the choice of reads and assembly algorithms for the analysis of viromes.

Microbial Genomics. February 2024

Dion Garrett, Graham Teakle, Rosemary Collier, James R. Bell, Sergio Cerezo-Medina, Ramiro Morales-Hojas

The currant-lettuce aphid (Nasonovia ribisnigri (Hemiptera: Aphididae) (Mosley)) is a cosmopolitan pest of outdoor lettuce. Until recently, the use of resistant cultivars was an effective method for managing N. ribisnigri. A resistant cultivar containing a single gene (Nr-locus), introduced in the 1980s, conferred complete resistance to feeding. Overreliance of this Nr-locus in lettuce resulted in N. ribisnigri's ability to break resistance mechanism. Our work attempts to understand which candidate gene(s) are associated with this resistance-breaking mechanism. We present two de novo draft assembles for N. ribisnigri genomes, corresponding to both avirulent (Nr-locus susceptible) and virulent (Nr-locus resistant) biotypes.. Out of the 18,872 differentially expressed genes, a single gene/locus was identified in N. ribisnigri that was shared between two resistant-breaking biotypes. This locus was further explored and validated in Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) experiments and has predicted localisations in both the cytoplasm and nucleus. This is the first study to provide evidence that a single gene/locus is likely responsible for the ability of N. ribisnigri to overcome the Nr-locus resistance in the lettuce host.

Insect Molecular Biology. February 2024

Ryan M. Mushinski, Yong Zhou, Ayumi Hyodo, Claudio Casola, Thomas W. Boutton

We investigated the interactions between livestock grazing history (none, moderate, heavy) and vegetation cover (grassland, juniper, oak) using a ∼ 70-year grazing experiment in west-central Texas. We explored effects on soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), microbial community composition, and function. The findings highlight how long-term livestock grazing and woody plant encroachment influence soil C, N, P cycles, altering soil microbial community structure and function. This study provides insights for savanna ecosystem management and integrating land cover effects into biogeochemical models for global change scenarios.

Geoderma.  January 2024

Guillermo Friis, Edward G. Smith, Catherine E. Lovelock, Alejandra Ortega, Alyssa Marshell, Carlos M. Duarte, John A. Burt

Biological systems occurring in ecologically heterogeneous and spatially discontinuous habitats provide an ideal opportunity to investigate the relative roles of neutral and selective factors in driving lineage diversification. The grey mangroves (Avicennia marina) of Arabia occur at the northern edge of the species' range and are subject to variable, often extreme, environmental conditions, as well as historic large fluctuations in habitat availability and connectivity resulting from Quaternary glacial cycles. Here, we analyse fully sequenced genomes sampled from 19 locations across the Red Sea, the Arabian Sea and the Persian/Arabian Gulf (PAG) to reconstruct the evolutionary history of the species in the region and to identify adaptive mechanisms of lineage diversification. Our results support a process of rapid diversification resulting from the combined effects of historical factors and ecological selection and reveal mangrove peripheral environments as relevant drivers of lineage diversity.

Molecular Ecology. January 2024

Quantifying microplastic dispersion due to density effects

Stride, Ben, Abolfathi, Soroush, Bending, Gary D. and Pearson, Jonathan M

An experimental study was conducted on how polymer density affects the transport and fate of microplastics in aquatic flows. For the first time, polypropylene (PP), polyethylene (PE), polymethyl methacrylate (PMMA), polyetheretherketone (PEEK), and polyvinyl chloride (PVC) were chemically stained and tested using solute transport techniques and velocities found among rivers in the natural environment (0.016 – 0.361 m/s). Except for PP, in most conditions microplastics exhibited similar transport characteristics to solutes regardless of density and established solute transport models were successfully implemented to predict their transport and fate.. This data is the first to provide microplastic suspension and deposition thresholds based on river velocity and polymer density, making a key contribution to research predicting microplastic fate and organismal exposure.

Journal of Hazardous Materials. January 2024

Distinct biogeographic patterns in Glomeromycotinian and Mucoromycotinian arbuscular mycorrhizal fungi across China: A meta-analysis

Zihao Liu, Jie Fang, Yucheng He, Gary D Bending, Bin Song, Yaping Guo, Xiaojie Wang, Zemin Fang, Jonathan M Adams

Fine root endophytes, recently reclassified as Mucoromycotinian arbuscular mycorrhizal fungi (M-AMF), are now recognized as functionally important as Glomeromycotinian AMF (G-AMF). Here, we investigated the biogeographic assemblies and ecological diversity patterns of both G-AMF and M-AMF, using published 18S rDNA amplicon datasets and associated metadata from 575 soil samples in six ecosystems across China. This study provides solid evidence that the two AMF groups have distinct ecological preferences at the continental scale in China, and also highlights the potential impacts of anthropogenic activities on distributions of AMF. These results advance our knowledge of the ecological differences between the two fungal groups in terrestrial ecosystems, suggesting the need for further field-based investigation that may lead to a more sophisticated understanding of ecosystem function and sustainable management.

Science of the Total Environment. December 2023

María Florencia Mammarella, Leandro Lucero, Nosheen Hussain, Aitor Muñoz-Lopez, Ying Huang, Lucia Ferrero, Guadalupe L Fernandez-Milmanda, Pablo Manavella, Moussa Benhamed, Martin Crespi, Carlos L Ballare, Jose Gutierrez-Marcos, Pilar Cubas, Federico Ariel

The long noncoding RNA (lncRNA) AUXIN-REGULATED PROMOTER LOOP (APOLO) recognizes a subset of target loci across the Arabidopsis thaliana genome by forming RNA–DNA hybrids (R-loops) and modulating local three-dimensional chromatin conformation. Here, we show that APOLO regulates shade avoidance syndrome by dynamically modulating expression of key factors. We show that direct application of APOLO RNA to leaves results in a rapid increase in auxin signaling that is associated with changes in the plant response to far-red light. Collectively, our data support the view that lncRNAs coordinate shade avoidance syndrome in A. thaliana, and reveal their potential as exogenous bioactive molecules. Deploying exogenous RNAs that modulate plant–environment interactions may therefore become a new tool for sustainable agriculture.

EMBO Journal. December 2023

Chaweewan Sirakawin, Dongfa Lin, Ziyue Zhou, Xiaoxin Wang, Rhianne Kelleher, Shangyuan Huang, Weimiao Long, Andre Pires-da Silva, Yu Liu, Jingjing Wang, Ilya A. Vinnikov

Vitamin A (VA) is a micronutrient essential for the physiology of many organisms, but its role in longevity and age-related diseases remains unclear. In this work, we used Caenorhabditis elegans to study the impact of various bioactive compounds on lifespan. We demonstrate that VA extends lifespan and reduces lipofuscin and fat accumulation while increasing resistance to heat and oxidative stress. This resistance can be attributed to high levels of detoxifying enzymes called glutathione S-transferases, induced by the transcription factor skinhead-1 (SKN-1). Notably, VA upregulated the transcript levels of skn-1 or its mammalian ortholog NRF2 in both C. elegans, human cells, and liver tissues of mice. Moreover, the loss-of-function genetic models demonstrated a critical involvement of the SKN-1 pathway in longevity extension by VA. Our study thus provides novel insights into the molecular mechanism of anti-aging and anti-oxidative effects of VA, suggesting that this micronutrient could be used for the prevention and/or treatment of age-related disorders.

Aging Cell. December 2023

Orin Courtenay, José F Marinho-Júnior, Maria Edileuza F Brito, Juliana FCLS Monteiro, Jeffrey J Shaw, Sinval P. Brandão-Filho

Human and wild rodent infection rates with Leishmania (Viannia) braziliensis are needed to differentiate transmission pathways in anthropogenically altered habitats.  In this study, human participants in northeast Brazil were tested by the leishmanin skin test (LST) and inspected for lesions/scars characteristic of American clinical leishmaniasis (ACL). Molecular (PCR/qPCR) test records of free-ranging rodents were available from a concurrent capture–mark–recapture study. Force of Infection (λ) and recovery (ρ) rates were estimated from cross-sectional and longitudinal datasets. The results show human exposure to L. (V.) braziliensis continues to be high despite the substantial drop in reported ACL cases in recent years. Spill-over transmission risk to humans from rodents in peridomestic habitats is likely supported by a rodent infection/transmission corridor linking houses, plantations, and the Atlantic Forest.

Pathogens. December 2023

George Muscatt, Ryan Cook, Andrew Millard, Gary D Bending, Eleanor Jameson

To investigate viral communities throughout the soil depth profile, we leveraged a publicly available metagenomic data set sampled from grassland soil in Northern California. In total, 10,196 non-redundant viral operational taxonomic units were recovered from soil between 20 cm and 115 cm below the surface. Viral diversity was assessed at both the population level and strain level to reveal diverse ecological and evolutionary patterns of virus-host interactions in surface and subsurface soils. Investigating viral microdiversity uncovered potential patterns of antagonistic co-evolution across both surface and subsurface soils. We have provided evidence for the potential of soil viruses to augment the remineralization of soil carbon. While we continue to yield a more comprehensive understanding of soil viral ecology, our work appeals to future researchers to further investigate subsurface viral communities.

Microbial Ecology. November 2023

Jacqueline L. Stroud, Simon J. Kemp, Craig J. Sturrock

In this study, new and traditional organic wastes (green waste compost, farmyard manure (FYM), anaerobic digestate or straw) were ploughed into an arable field experiment at a range of rates (1–3 t C ha−1) and under spring and winter cropping rotations for 5 years. The stability of the soil surface structure (<5 cm) was assessed in Years 3, 4 and 5 to guide the use of organic wastes in arable field management. In conclusion, to achieve a stable soil surface structure, a 150% improvement in aggregate stability would be needed here and ploughing in organic wastes was not a successful management approach on these arable field experiments.

Soil Use and Management. November 2023

Ben Stride, Charlotte Dykes, Soroush Abolfathi, Modupe Jimoh, Gary D Bending, Jonathan Pearson

The transport of microplastics within urban water systems remains poorly understood, with little prior research on their behaviour within manhole configurations. This study represents the first to measure and model the transport dynamics of microplastics within circular and square manholes under different hydraulic scenarios. The transport and fate of polyethylene (PE) was quantified and compared to solutes (Rhodamine WT dye) using energy losses, residence time distributions (RTDs), and mixing models within surcharging and overflowing manholesThis establishes the deconvolution method as the most accurate and appropriate model to accurately predict microplastic mixing in manholes and urban drainage systems.

Science of the Total Environment. November 2023

Vinko Zadjelovic, Robyn J. Wright, Chiara Borsetto, Jeannelle Quartey, Tyler N. Cairns, Morgan G. I. Langille, Elizabeth M. H. Wellington & Joseph A. Christie-Oleza

In- and ex-situ incubations were used to characterise the riverine plastisphere taxonomically and functionally in order to determine whether antibiotics within the water influenced the ARG profiles in these microbiomes and how these compared to those on natural surfaces such as wood and their planktonic counterparts. Our results provide insights into the capacity of the riverine plastisphere to harbour a distinct set of potentially pathogenic bacteria and function as a reservoir of ARGs. The environmental impact that plastics pose if they act as a reservoir for either pathogenic bacteria or ARGs is aggravated by the persistence of plastics in the environment due to their recalcitrance and buoyancy. Nevertheless, the high similarities with microbiomes growing on natural co-occurring materials and even more worrisome microbiome observed in the surrounding water highlights the urgent need to integrate the analysis of all environmental compartments when assessing risks and exposure to pathogens and ARGs in anthropogenically-impacted ecosystems.

Microbiome. November 2023

Megan L. Purchase, Gary D. Bending and Ryan M. Mushinski

Volatile reactive nitrogen oxides (NOy) are significant atmospheric pollutants, including NOx (nitric oxide [NO] + nitrogen dioxide [NO2]) and NOz (nitrous acid [HONO] + nitric acid [HNO3] + nitrogen trioxide [NO3] + ...). NOy species are products of nitrogen (N) cycle processes, particularly nitrification and denitrification. Biogenic sources, including soil, account for over 50% of natural NOy emissions to the atmosphere, yet emissions from soils are generally not included in atmospheric models as a result of a lack of mechanistic data. This work is a unique investigation of NOy fluxes on a landscape scale, taking a comprehensive set of land-use types, human influence, and seasonality into account to determine large-scale heterogeneity to provide a basis for future modeling and hypothesis generation

Environmental Science &Technology. October 2023

Holly Acford-Palmer, Monica Campos, Janvier Bandibabone, Sévérin N’Do, Chimanuka Bantuzeko, Bertin Zawadi, Thomas Walker, Jody E. Phelan, Louisa A. Messenger, Taane G. Clark & Susana Campino

Vector control strategies have been successful in reducing the number of malaria cases and deaths globally, but the spread of insecticide resistance represents a significant threat to disease control. To support the continuous efficacy of vector control strategies, it is essential to monitor insecticide resistance using molecular surveillance tools. In this study, we developed an amplicon sequencing (“Amp-seq”) approach targeting An. funestus, and using multiplex PCR, dual index barcoding, and next-generation sequencing for high throughput and low-cost applications. Overall, our panel represents an extendable and much-needed method for the molecular surveillance of insecticide resistance in An. funestus populations.

Scientific Reports. October 2023

Dennis Alexander Tebbe, Charlotte Gruender, Leon Dlugosch, Kertu Lõhmus, Sönke Rolfes, Martin Könneke, Yin Chen, Bert Engelen and Hendrik Schaefer

Saltmarshes are highly productive environments, exhibiting high abundances of organosulfur compounds. Dimethylsulfoniopropionate (DMSP) is produced in large quantities by algae, plants, and bacteria and is a potential precursor for dimethylsulfoxide (DMSO) and dimethylsulfide (DMS). DMSO serves as electron acceptor for anaerobic respiration leading to DMS formation, which is either emitted or can be degraded by methylotrophic prokaryotes. Major products of these reactions are trace gases with positive (CO2, CH4) or negative (DMS) radiative forcing with contrasting effects on the global climate. Here, we investigated organic sulfur cycling in saltmarsh sediments and followed DMSO reduction in anoxic batch experiments. Compared to previous measurements from marine waters, DMSO concentrations in the saltmarsh sediments were up to ~300 fold higher.

ISME journal. October 2023

Yueyue Si, Yizhu Zhu, Ian Sanders, Dorothee B. Kinkel, Kevin J. Purdy & Mark Trimmer

Although a sink for N2O through biological fixation has been observed in the Pacific, the regulation of N2O-fixation compared to canonical N2-fixation is unknown. Here we show that both N2O and N2 can be fixed by freshwater communities but with distinct seasonalities and temperature dependencies. N2O fixation appears less sensitive to temperature than N2 fixation, driving a strong sink for N2O in colder months. Moreover, by quantifying both N2O and N2 fixation we show that, rather than N2O being first reduced to N2 through denitrification, N2O fixation is direct and could explain the widely reported N2O sinks in natural waters. Analysis of the nitrogenase (nifH) community suggests that while only a subset is potentially capable of fixing N2O they maintain a strong, freshwater sink for N2O that could be eroded by warming.

Nature Communications. October 2023

Elizabeth Sands, Sian Davies, Richard John Puxty, Valerie Vergé, François-Yves Bouget, David John Scanlan, Isabelle Alice Carre

Phytoplankton are exposed to dramatic variations in light quality when cells are carried by upwelling or downwelling currents or encounter sediment. We investigated the potential impact of light quality changes in Ostreococcus, a key marine photosynthetic picoeukaryote, by analysing changes in its transcriptome, pigment content and photophysiology after acclimation to monochromatic red, green or blue lightThe results demonstrate that light quality can have a major influence on the physiology of eukaryotic phytoplankton and suggest that different light quality environments can drive selection for diverse patterns of responsiveness and environmental niche partitioning.

Journal of Experimental Botany. September 2023

A. Coffey, Robert Lillywhite, Oyinlola Oyebode

Meat consumption plays a role in both health and environmental burden. Consumption of meat alternatives may reduce these harms. The aim was to compare meat products and their plant-based alternatives on nutritional parameters, GHGE and price to examine if it is feasible and beneficial for policymakers and health professionals to recommend meat alternatives.Overall, this paper found that meat alternatives are likely to be better for health according to most parameters, while also being more environmentally friendly, with lower GHGEs. However, the higher price of these products may be a barrier to switching to meat alternatives for the poorest in society.

Journal of Human Nutrition and Dietetics. August 2023

Julie Rushmore, Brianna R. Beechler, Hannah Tavalire, Erin E. Gorsich, Bryan Charleston, Anne Devan-Song, Caroline K. Glidden, Anna E. Jolles

Here, we analyzed African buffalo social networks to quantify variation in close contacts, examined drivers of contact heterogeneity, and investigated how the observed contact patterns affect pathogen invasion likelihoods for a wild social ungulate. Although the observed herd was well connected, with most individuals contacting each other during each bimonthly interval, our analyses revealed striking heterogeneity in close-contact associations among herd members. Network analysis showed that individual connectivity was stable over time and that individual age, sex, reproductive status, and pairwise genetic relatedness were important predictors of buffalo connectivityThese findings highlight the role susceptible calves may play in the transmission of pathogens within the herd. We also demonstrate that, at time scales relevant to infectious pathogens found in nature, the observed level of connectivity affects pathogen invasion likelihoods for a wide range of infectious periods and transmissibilities. Ultimately, our study identifies key predictors of social connectivity in a social ungulate and illustrates how contact heterogeneity, even within a highly connected herd, can shape pathogen invasion likelihoods.

Ecology and Evolution. August 2023

Suhad AA Al-Salihi and Fabrizio Alberti

Fungi represents a rich repository of taxonomically restricted, yet chemically diverse, secondary metabolites that are synthesised via specific metabolic pathways. An enzyme’s specificity and biosynthetic gene clustering are the bottleneck of secondary metabolite evolution. Trichoderma harzianum M10 v1.0 produces many pharmaceutically important molecules; however, their specific biosynthetic pathways remain uncharacterised. Our genomic-based analysis of this species reveals the biosynthetic diversity of its specialised secondary metabolites, where over 50 BGCs were predicted, most of which were listed as polyketide-like compounds associated clusters. Revealing the biogenetic background of these natural molecules is a step forward towards the expansion of their chemical diversification via engineering their biosynthetic genes heterologously, and the identification of their role in the interaction between this fungus and its biotic/abiotic conditions as well as its role as bio-fungicide. 

Journal of Fungi. August 2023

Tayseer Jibreel, Altayeb Khogali, Maribel Jiménez, Raiyed, Adeel, Osman Dakein, Bashir Alsharif, Noteila M. Khalid, Omran F. Osman, Bakri Y M Nour, Gamal Hassan Mohamed, Ricardo Molina, Ana Vidal, Ramón Díaz-Regañón, Margriet den Boer, Jorge Alvar, Orin Courtenay, D. A. Elnaiem

Visceral leishmaniasis (VL, kala azar), caused by Leishmania donovani, transmitted by Phlebotomus orientalis, is a serious systemic disease that causes high morbidity and mortality rates in Sudan and other parts of East Africa and the world. Despite progress in understanding the epidemiology of the disease in East Africa, little is known about the host preference of P. orientalis in kala azar endemic villages of Sudan, which have some of the highest VL incidence rates in the world. The present study used host choice experiments and blood-meal identification approaches to determine the host preference of P. orientalis in kala azar endemic villages in Gedarif state, eastern Sudan. Although the order of host preference varied by location, it was clear that cows are the most preferred host of P. orientalis in the area. Results are discussed in relation to the role of domestic/livestock animals in VL zoopotentiation and zooprophylaxis. Inference is made on the potential impact of insecticide treatment of cows in control of the vector and the transmission of VL in Sudan and other parts of East Africa.

Medical and Veterinary Entomology. August 2023

Stride, Ben, Dykes, Charlotte, Abolfathi, Soroush, Jimoh, Modupe, Bending, Gary D. and Pearson, Jonathan M

The transport of microplastics within urban water systems remains poorly understood, with little prior research on their behaviour within manhole configurations. This study represents the first to measure and model the transport dynamics of microplastics within circular and square manholes under different hydraulic scenarios. The transport and fate of polyethylene (PE) was quantified and compared to solutes (Rhodamine WT dye) using energy losses, residence time distributions (RTDs), and mixing models within surcharging and overflowing manholes. The bulk mass of solute and PE concentrations followed similar flow paths across all conditions except for 17.3 ± 7.9 % of PE mass that was immobilized in a dead zone above the inlet pipe for manholes with a surcharge to pipe diameter ratio ≥2. Consequently, these microplastics only exit after a significant change in hydraulic regime occurs, causing microplastics to be at risk of being contaminated over a prolonged duration. No significant mixing differences for PE and solutes were found between manhole geometries. The deconvolution method outperformed the ADZ model with goodness of fit (Rt2) values of 0.99 (0.60) and 1.00 (0.89) for PE and solute mixing respectively. This establishes the deconvolution method as the first mixing model to accurately predict microplastic mixing.

Science of the Total Environment. July 2023

Karina Spoyalo, Annie Lalande, Chantelle Rizan, Sophia Park, Janet Simons, Philip Dawe, Carl J Brown, Robert Lillywhite, Andrea J MacNeil

Patients with uncomplicated acute surgical conditions were retrospectively evaluated for unnecessary bloodwork according to the triple bottom line, quantifying the impacts on patients, healthcare costs and greenhouse gas emissions. The carbon footprint of common laboratory investigations was estimated using PAS2050 methodology, including emissions generated from the production, transport, processing and disposal of consumable goods and reagents. We found considerable overuse of laboratory investigationsresulting in unnecessary burden to patients, hospitals and the environment. This study identifies an opportunity for resource stewardship and exemplifies a comprehensive approach to quality improvement.

BMJ Open Quality. July 2023

I. Dummett, C. J. Sturrock, J. L. Stroud

We received multiple requests from farmers in 2018 for research into the impact of slug pellets on earthworms because they had been told that ferric-based pellets were ‘worm-friendly’. We measured soil fauna feeding activities within Lumbricus terrestris middens on a replicated field plot experiment comparing the recommended product rates of a metaldehyde (4%) based or ferric phosphate EDDS (3%) based slug pellets. Our results suggest an avoidance behaviour response. A consultation with farmers (n=68) rated this information service as useful and indicated widespread interest in minimizing the effects of pesticides on non-target soil fauna.

Soil Use & Management June 2023

Press Release

Abigail L Whittock, Xuefei Ding, Xavier E Ramirez Barker, Nazia Auckloo, Rebecca A Sellers, Jack M Woolley, Krishnan Tamareselvy, Marine Vincendet, Christophe Corre, Emma Pickwell-MacPherson and Vasilios G Stavros

Biomimicry has become a key player in researching new materials for a whole range of applications. In this study, we have taken a crude extract from the red algae Palmaria palmata containing mycosporine-like amino acids – a photoprotective family of molecules. We have applied the crude extract onto a surface to assess if photoprotection, and more broadly, light-to-heat conversion, is retained; we found it is. Considering sunscreens as a specific application, we have performed transmission and reflection terahertz spectroscopy of the extract and glycerol to demonstrate how one can monitor stability in real-world applications.

Chemical Science. June 2023

Modelling microplastic and solute transport in vegetated flows

Stride, Ben, Abolfathi, Soroush , Odara, N. O. M., Bending, Gary D. and Pearson, Jonathan M

This study was conducted to investigate the underlying physical transport mechanisms of microplastics over submerged canopies across a range of flow conditions common in the natural environment. The study determined and compared the mixing and dispersion processes for microplastics and solutes utilizing fluorometric tracing techniques. A hydrodynamic model was developed based on the advection-dispersion equation for quantifying microplastic mixing in submerged canopies. Longitudinal dispersion coefficients for neutrally buoyant microplastics (polyethylene) and solutes were significantly correlated within submerged model vegetation irrespective of the complexity of the flow regime. Hydrodynamic and solute transport models were shown to be capable of robust predictions of mixing for neutrally buoyant microplastics in environmental flows over a canopy, facilitating a new approach to quantify microplastic transport and fate.

Water Resources Research. May 2023

Niche differentiation of Mucoromycotinian and Glomeromycotinian arbuscular mycorrhizal fungi along a 2-million-year soil chronosequence

Thomas M. Mansfield, Felipe E. Albornoz, Megan H. Ryan, Gary D. Bending & Rachel J. Standish

Current literature suggests ecological niche differentiation between co-occurring Mucoromycotinian arbuscular mycorrhizal fungi (M-AMF) and Glomeromycotinian AMF (G-AMF), but experimental evidence is limited. We investigated the influence of soil age, water availability (wet and dry), and plant species (native Microlaena stipoides and exotic Trifolium subterraneum) on anatomical root colonisation and DNA profiles of M-AMF and G-AMF under glasshouse conditions. Our findings are experimental evidence of ecological niche differentiation of M-AMF and G-AMF and invite further exploration into interactive effects of abiotic and biotic factors on their communities along successional trajectories.

Mycorrhiza. May 2023

Linda M. Westermann, Ian D. E. A. Lidbury Chun-Yang Li, Ning Wang, Andrew R. J. Murphy, Maria del Mar Aguilo Ferretjans, Mussa Quareshy, Muralidharan Shanmugan , Alberto Torcello-Requena, Eleonora Silvano, Yu-Zhong Zhang, Claudia A. Blindauer, Yin Chen, David J. Scanlan

In marine systems, the availability of inorganic phosphate can limit primary production leading to bacterial and phytoplankton utilization of the plethora of organic forms available. Among these are phospholipids that form the lipid bilayer of all cells as well as released extracellular vesicles. However, information on phospholipid degradation is almost nonexistent despite their relevance for biogeochemical cycling. Here, we identify complete catabolic pathways for the degradation of the common phospholipid headgroups phosphocholine (PC) and phosphorylethanolamine (PE) in marine bacteria.

Science Advances. April 2023

Chantelle Rizan, Robert Lillywhite, Malcolm Reed, Mahmood F Bhutta

The aim of this study was to evaluate the carbon footprint of products used within five common operations, and to identify the biggest contributors (hotspots). We determined the carbon footprint of the products used in each of the five operations, alongside greatest contributors through analysis of individual products and of underpinning processesAcross the five operations, 23% of product types were responsible for 80% of the operation carbon footprint. Mean average contribution from production of single-use items was 54%, decontamination of reusables 20%, waste disposal of single-use items 8%, production of packaging for single-use items 6% and linen laundering 6%. Change in practice and policy should be targeted towards those products making greatest contribution, and should include reducing single-use items and switching to reusables, alongside optimising processes for decontamination and waste disposal, modelled to reduce carbon footprint of these operations by 23%-42%.

Journal of the Royal Society of Medicine. April 2023

Rebecca V. Southwell, Sally L. Hilton, Jonathan M. Pearson, Laurence H. Hand, Gary D. Bending

Before agrochemicals can be registered and sold, the chemical industry is required to perform regulatory tests to assess their environmental persistence, using defined guidelines. Aquatic fate tests (e.g. OECD 308) lack environmental realism as they are conducted under dark conditions and in small-scale static systems, which can affect microbial diversity and functionality. In this study, water-sediment microflumes were used to investigate the impact of these deficiencies in environmental realism on the fate of the fungicide, isopyrazam. We conclude that both water velocity and non-UV light increased isopyrazam dissipation, but the contribution of light depended on the flow conditions. These differences may have resulted from impacts on microbial communities and via mixing processes, particularly hyporheic exchange. Inclusion of both light and flow in studies could improve the extent they mimic natural environments and predict chemical environmental persistence, thus bridging the gap between laboratory and field studies.

Science of the Total Environment. April 2023