Paul Dyson

• BSc, PhD
• Professor at Swansea University

Bacterial cancer therapy (BCT) is emerging as an important option for the treatment of solid tumours, with promising outcomes in preclinical trials. Further progress is hampered by an incomplete understanding of how oncotropic bacteria, such as attenuated strains of Salmonella enterica serovar Typhimurium, colonise tumours and the responses of both...

Bacterial cancer therapy (BCT) is emerging as an important option for treatment of solid tumours, with promising outcomes in preclinical trials. Further progress is hampered by an incomplete understanding of how oncotropic bacteria, such as attenuated strains of Salmonella enterica serovar Typhimurium, colonise tumours and the responses of both the...

The WHO has compiled a list of pathogens that urgently require new antibiotics in response to the rising reports of antibiotic resistance and a diminished supply of new antibiotics. At the top of this list is fluoroquinolone-resistant Salmonella typhi, fluoroquinolone-resistant Shigella spp. and vancomycin-resistant Enterococcus faecium. Although t...

The discoveries of penicillin and streptomycin were pivotal for infection control with the knowledge subsequently being used to enable the discovery of many other antibiotics currently used in clinical practice. These valuable compounds are generally derived from mesophilic soil microorganisms, predominantly Streptomyces species. Unfortunately, pro...

Background Bacterial cancer therapy was first trialled in patients at the end of the nineteenth century. More recently, tumour-targeting bacteria have been harnessed to deliver plasmid-expressed therapeutic interfering RNA to a range of solid tumours. A major limitation to clinical translation of this is the short-term nature of RNA interference in...

This overview initially describes insect immune reactions and then brings together present knowledge of the interactions of vector insects with their invading parasites and pathogens. It is a way of introducing this Special Issue with subsequent papers presenting the latest details of these interactions in each particular group of vectors. Hopefull...

This overview initially describes insect immune reactions and then brings together present knowledge of the interactions of vector insects with their invading parasites and pathogens. It is a way of introducing this special issue with subsequent papers presenting the latest details of these interactions in each particular group of vectors. Hopefull...

BACKGROUND: Bacterial cancer therapy was first trialled in patients at the end of the nineteenth century. More recently, tumour-targeting bacteria have been harnessed to deliver plasmid-expressed therapeutic interfering RNA to a range of solid tumours. A major limitation to clinical translation of this is the short-term nature of RNA interference...

Introduction Insecticidal RNAi is a targeted pest insect population control measure. The specificity of insecticidal RNAi can theoretically be enhanced by using symbiotic bacteria with a narrow host range to deliver RNAi, an approach termed symbiont-mediated RNAi (SMR), a technology we have previously demonstrated in the globally-invasive pest spec...

Despite intramuscular vaccines saving millions of lives, constant devastating waves of SARS-CoV-2 infections continue. The elimination of COVID-19 is challenging, but necessary in order to avoid millions more people who would suffer from long COVID if we fail. Our paper describes rapidly advancing and innovative therapeutic strategies for the early...

Pseudarthrobacter sulfonivorans strain Ar51 can degrade crude oil and multi-substituted benzene compounds efficiently at low temperatures. However, it cannot degrade hydroquinone, which is a key intermediate in the degradation of several other compounds of environmental importance, such as 4-nitrophenol, g-hexachlorocyclohexane, 4-hydroxyacetopheno...

Insecticidal RNAi is a targeted pest insect population control measure. The specificity of insecticidal RNAi can theoretically be enhanced by using symbiotic bacteria with a narrow host range to deliver RNAi, an approach termed symbiont-mediated RNAi (SMR), a technology we have previously demonstrated in the globally-invasive pest species Western F...

Symbiont mediated RNAi (SMR) is a promising method for precision control of pest insect species such as Western Flower Thrips (WFT). Two species of bacteria are known to be dominant symbiotic bacteria in WFT, namely BFo1 and BFo2 (Bacteria from Frankliniella occidentalis 1 and 2), as we here confirm by analysis of next-generation sequence data deri...

We report the discovery and functional characterization of a new bacterial tRNA species. The tRNA-Asp-AUC, from a fast-growing desert streptomycete, decodes GAU codons. In the absence of queuosine tRNA anticodon modification in streptomycetes, the new tRNA circumvents inefficient wobble base-pairing during translation. The tRNA, which is constituti...

This article presents an overview of paratransgenesis as a strategy to control pathogen transmission by insect vectors. It first briefly summarises some of the disease-causing pathogens vectored by insects and emphasises the need for innovative control methods to counter the threat of resistance by both the vector insect to pesticides and the patho...

RNA interference (RNAi) has emerged as a widely used approach for reverse genetic analysis in eukaryotes. In insects, RNAi also has an application in the control of insect pests. Several methods have been developed for delivery of interfering RNA in insects, with varying outcomes for different species. Here we describe how a bacterial symbiont can...

Traditional Irish medicines are often intertwined with ritual and spirituality, making it difficult to substantiate the validity of their claims. In this manuscript, we use molecular and microscopic techniques to investigate some microorganisms that might be responsible for the reputed healing properties of an ancient Irish soil cure known as the B...

Rhodnius prolixus is an insect vector of two flagellate parasites, Trypanosoma rangeli and Trypanosoma cruzi, the latter being the causative agent of Chagas disease in Latin America. The R. prolixus neuroendocrine system regulates the synthesis of the steroid hormone ecdysone, which is essential for not only development and molting but also insect...

Background Siderophores are small molecule iron-chelators produced by microorganisms and plants growing mostly under low iron conditions. Siderophores allow iron capture and transport through cell membranes into the cytoplasm, where iron is released for use in biological processes. These bacterial iron uptake systems can be used for antibiotic conj...

In insect reverse genetics, dietary delivery of interfering RNAs is a practical approach in nonmodel species, such as thrips, whose small size, and feeding behavior restricts the use of other delivery methods. In a laboratory context, an unsuitable diet could confound the interpretation of an RNA interference (RNAi) phenotype, however well-formulat...

The Qinghai-Tibet Plateau glaciers are an important carrier of mercury (Hg). With global warming, Hg enters into the downstream ecosystem in the melt waters, threatening human health and ecosystem security in the region. Methylmercury (MeHg), which has higher toxicity than Hg itself, is converted from inorganic Hg. However, little is known about th...

Actinobacteria are known for their metabolic potential of producing diverse secondary metabolites such as antibiotics. Actinobacteria also playimportant roles in biogeochemical cycling and how soils develop. However, little is known about the effect of the vegetation type on the actinobacterial community structures in soils from arid regions. For t...

A novel actinobacterial strain, designated Z022T, isolated from a soil sample collected from Dangxiong in Tibet Autonomous Region (PR China), was determined by polyphasic taxonomic approach. The organism had chemotaxonomic and morphological properties consistent with its classification in the genus Streptomyces. Strain Z022T showed high similarity...

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are the principal vectors of several notable viral pathogens infecting animal livestock. Sickness and animal deaths caused by the Culicoides-transmitted bluetongue virus, as well as the recent Schmallenberg virus outbreak, have threatened the livestock industry in Europe. Recent studi...

Antibiogram of novel species Streptomyces sp. myrophorea, isolate McG1

In an effort to stem the rising tide of multi-resistant bacteria, researchers have turned to niche environments in the hope of discovering new varieties of antibiotics. We investigated an ethnopharmacological (cure) from an alkaline/radon soil in the area of Boho, in the Fermanagh Scarplands (N. Ireland) for the presence of Streptomyces, a well-kno...

Boho Streptomyces A Novel Alkaliphilic Streptomyces Inhibits ESKAPE Pathogens. In an effort to stem the rising tide of multi-resistant bacteria, researchers have turned to niche environments in the hope of discovering new varieties of antibiotics. We investigated an ethnopharmacological (cure) from an alkaline/radon soil in the area of Boho, in th...

A novel actinobacterial strain, designated S10T, was isolated from a sand sample collected from the Qaidam Basin in Qinghai province, China. The strain S10T exhibited antibacterial activity against MRSA. The taxonomic position of the strain S10T was determined by a polyphasic approach. There were six copies of 16S rDNA in S10T which were not same e...

It is time to reduce the environmental footprint of insect pest control. Bacteria are the ideal tools for developing 'smart' precision bio-insecticides and preventing disease transmission by insects.

Drug resistance is a major problem in antibacterial chemotherapy. Apidaecins, which refer to a series of small, proline-rich antimicrobial peptides, are predominantly active against many drug-resistant bacteria. The apidaecins have special antibacterial mechanisms, and are non-toxic for human cells, a prerequisite for using them as novel antibiotic...

The dissacharide trehalose is an important intracellular osmoprotectant and the OtsA/B pathway is the principal pathway for trehalose biosynthesis in a wide range of bacterial species. Scaffolding proteins and other cytoskeletal elements play an essential role in morphogenetic processes in bacteria. Here we describe how OtsA, in addition to its rol...

Growth curves of strains Ar0111 (ΔotsA + PotsA-otsA), Ar0112 (ΔotsA + PotsA-otsAEc), Ar0113 (ΔotsA + PotsA-otsB), Ar0114 (ΔotsA + PotsA-dsbA), Ar0115 (ΔotsA + PotsA-otsAR36A), Ar0116 (ΔotsA + PotsA-otsA::mCherry) grown in LB. (DOCX)

Determination of intracellular trehalose concentrations. Intracellular concentrations were obtained from cells grown to mid-log phase and standardized with respect to wet weights. (A) Intracellular trehalose concentration of Ar0001 (wt), Ar0002 (ΔotsA), Ar0008 (wt + treFEc) and Ar0112 (ΔotsA + otsAEc) grown in LB medium; (B) Intracellular trehalose...

The percentage of cell aggregates with circumference >4 um in early log-phase cultures of wild-type (Ar0001), ΔotsA (Ar0002), wild-type + treFEc (Ar0008) grown in LB medium and wild-type (Ar0001) grown in LB medium amended to a final concentration of 0.57 M NaCl. (DOCX)

Polymerization of variant OtsA proteins. (DOCX)

Strain Ar0003 (Wild type strain, 1); Ar0111 (ΔotsA + PotsA-otsA, 2); Ar0002 (ΔotsA, 3); Ar0004 (wild-type + up-otsA, 4) Ar0010 (wild-type + up-otsAEC, 5); Ar0011 (wild-type + up-otsAR36A, 6) were grown on minimal medium (A), minimal medium+ 4 mM trehalose (B), minimal medium + 0.57 M NaCl (C), minimal medium + 4mM trehalose + 0.57 M NaCl (D). (DOCX...

Reduced septum formation associated with growth of myceloids. NCW, DAPI, DIC and merged images of representative early log-phase myceloids of (A) strain Ar0002 (ΔotsA) grown in LB; (B) strain Ar0003 (wild-type with empty vector) grown in LB amended to a final concentration of 0.57 M NaCl; (C) strain Ar0012 (wild-type with treCEc) grown in LB. Black...

Sizes of OtsA protein multimers previously denatured in 4M urea and then extensively dialysed to remove all urea, measured by dynamic light scattering. (DOCX)

Analysis of protein multimers of OtsAEc and OtsAR36A. (A) Sizes and abundance of multimeric structures as determined by dynamic light scattering. (B) Negative-stained TEM images of the respective protein structures. (DOCX)

Pest control in agriculture employs diverse strategies, among which the use of predatory insects has steadily increased. The use of several species within the genus Orius in pest control is widely spread, particularly in Mediterranean Europe. Commercial mass rearing of predatory insects is costly, and research efforts have concentrated on diet mani...

Insight into animal biology and development provided by classical genetic analysis of the model organism Drosophila melanogaster was an incentive to develop advanced genetic tools for this insect. But genetic systems for the over one million other known insect species are largely undeveloped. With increasing information about insect genomes resulti...

Importance: Polar growth is an intricate manner of growth for accomplishing a complicated morphology, employed by a wide range of organisms across the kingdoms of life. The tip extension of Streptomyces hyphae is one of the most pronounced examples of polar growth among bacteria. The expansion of the cell wall by tip extension is thought to be fac...

A novel actinobacterial strain, designated Z1027T, was isolated from a soil sample collected near the Tuotuo river, Qinghai-Tibet Plateau (China). The strain exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus. The strain Z1027T identity was determined using a polyphasic taxonomic approach. The organism has chemotaxo...

Pseudarthrobacter sulfonivorans strain Ar51, a psychotrophic bacterium isolated from the Tibet permafrost of China, can degrade crude oil and multi benzene compounds efficiently in low temperature. Here we report the complete genome sequence of this bacterium. The complete genome sequence of Pseudarthrobacter sulfonivorans strain Ar51, consisting o...

RNA interference (RNAi) methods for insects are often limited by problems with double-stranded (ds) RNA delivery, which restricts reverse genetics studies and the development of RNAi-based biocides. We therefore delegated to insect symbiotic bacteria the task of: (i) constitutive dsRNA synthesis and (ii) trauma-free delivery. RNaseIII-deficient, ds...

Arthrobacter strain A3, a psychotrophic bacterium isolated from the Tian Shan Mountain of China, can degrade the cellulose and synthesis the long-chain hydrocarbons efficiently in low temperature. Here we report the complete genome sequence of this bacterium. The complete genome sequence of Arthrobacter strain A3, consisting of a cycle chromosome w...

Actinobacteria are typically soil bacteria that have important roles in soil development and biogeochemical cycling. However, little is known about the occurrence or the succession of communities of Actinobacteria in new habitats. In this study, we investigated the diversity and succession of the actinobacterial communities that inhabited the forel...

Obligate bacterial symbionts are widespread in many invertebrates, where they are often confined to specialized host cells and are transmitted directly from mother to progeny. Increasing numbers of these bacteria are being characterized but questions remain about their population structure and evolution. Here we take a comparative genomics approach...

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titres. In this study, genes encoding key proteins involved in...

ABSTRACT Background: As an essential protein for bacterial cell division, the tubulin-like FtsZ protein has been selected as a target for development of next generation antimicrobials. PC190723 is a fluoride-containing benzamide compound developed as a FtsZ inhibitor that selectively inhibits growth of multidrug resistant Gram-positive bacteria. Ou...

Streptomyces are non-motile, saprophytic Gram-positive prokaryotes that are important as commercial producers of antibiotics. They possess a large (between 6 and 10 Mb) linear chromosome. Growth is by hyphal tip extension and branching, with subsequent erection of sporulating aerial hyphae. Primary metabolism utilizes carbon obtained from complex b...

The actinomycetes are well-known bioactive natural product producers, comprising the Streptomycetes, the richest drug-prolific family in all kingdoms, producing therapeutic compounds for the areas of infection, cancer, circulation, and immunity. Completion and annotation of many actinomycete genomes has highlighted further how proficient these bact...

The family Streptomycetaceae comprises the genera Streptomyces, Kitasatospora, and Streptacidiphilus that are very difficult to differentiate both with genotypic and phenotypic characteristics. A separate generic status for Kitasatospora and Streptacidiphilus is questionable. Members of the family can be characterized as non-acid-alcohol-fast actin...

Dps proteins are members of an extensive family of proteins that oxidise and deposit iron in the form of ferric oxide, and are also able to bind DNA. Ferroxidation centres are formed at the interface of anti-parallel dimers, which further assemble into dodecameric nanocages with a hollow core where ferric oxide is deposited. Streptomyces coelicolor...

The Qinghai-Tibet Plateau is sensitive to climate change, with ecosystems that are important with respect to scientific research. Here high-throughput DNA pyrosequencing was used to assess bacterial diversity within different alpine grassland ecosystems of the Qinghai-Tibet Plateau, China. In total, 34,759 sequences were obtained for the three ecos...

Streptomyces violaceusniger strain SPC6 is a halotolerant streptomycete isolated from the Linze desert in China. The strain has a very high growth rate and a short life cycle for a streptomycete. For surface-grown cultures, the period from spore germination to formation of colonies with mature spore chains is only 2 days at 37°C. Additionally, the...

We report the 4,385,577-bp high-quality draft assembly of the bacterial symbiont Rhodococcus rhodnii strain LMG5362, isolated from the gut of Rhodnius prolixus (Hemiptera, Reduviidae, Triatominae), the principle vector of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. This sequence might provide useful information for sub...

Dps proteins are found almost ubiquitously in bacterial genomes and there is now an appreciation of their multifaceted roles in various stress responses. Previous studies have shown that this family of proteins assemble into dodecamers and their quaternary structure is entirely critical to their function. Moreover, the numbers of dps genes per bact...

Antibiotic-producing Streptomyces are complex bacteria that remodel global transcription patterns and their nucleoids during development. Here, we describe a novel developmentally regulated nucleoid-associated protein, DdbA, of the genus that consists of an N-terminal DNA-binding histone H1-like domain and a C-terminal DksA-like domain that can pot...

Phylogenetic reconstruction revealed that most Actinobacterial orthologs of S. coelicolor SCO2837, encoding a metal-dependent galactose oxidase-like protein, are found within Streptomyces and were probably acquired by horizontal gene transfer from fungi. Disruption of SCO2837 (glxA) caused a conditional bld phenotype that could not be reversed by e...

GC content (%) of Streptomyces and S. aurantiaca genomes and SCO2837 (glxA) orthologs used in GC content comparisons. Only assembled genome sequences were included. ORF name is indicated when more than one glxA-like sequence per genome is present. (DOC)

Diagram representing SCO2837 (glxA) genetic locus and DNA fragments used in sub-cloning experiments. The position of transposon insertions is indicated by gray vertical arrows, while the putative promoter predicted by PromBase is indicated by a striped arrow with chromosome position indicated. Refer to [19] for a detailed map of Tn5062. (TIF)

Neighbour-Joining Bootstrap phylogenetic tree generated using protein sequences displaying similar domain composition and organisation to GlxA. Numbers at branch nodes indicate bootstrap values. (TIF)

The nature of microbial communities and their relation to enzyme activities in desert soils is a neglected area of investigation. To address this, the bacterial diversity and distribution and soil physico-chemical factors were investigated in the soil crust, the soil beneath the crust and rhizosphere soil at the southeast edge of the Tengger Desert...

This study investigated nitrogen removal from aquaculture wastewater in laboratory-scale biofilters treating saline aquaculture wastewater. Alongside the monitoring of water chemistry, changes to the total bacterial communities and ammonia oxidizing bacterial (AOB) communities were characterised using DNA based techniques. Three replicate flood/dra...

[This corrects the article on p. e25593 in vol. 6.].

The DpsA protein plays a dual role in Streptomyces coelicolor, both as part of the stress response and contributing to nucleoid condensation during sporulation. Promoter mapping experiments indicated that dpsA is transcribed from a single, sigB-like dependent promoter. Expression studies implicate SigH and SigB as the sigma factors responsible for...

Trehalose is a chemical chaperone known to protect a variety of organisms against cold stress. Members of the genus Arthrobacter, which belongs to the Actinomycetales group, exhibit strong resistance to stress conditions, but exactly how trehalose synthesis is regulated in conditions of cold stress is still unknown. Here, we report that Arthrobacte...

To date, the function of only two of the 34 predicted serine/threonine protein kinases (STPKs) of Streptomyces coelicolor has been described. Here we report functional analysis of pknB and two linked genes, fhaAB, encoding forkhead-associated (FHA) domain proteins that are part of a highly conserved gene locus in actinobacteria. In contrast to the...

Enriched phosphoproteomes of (A) M145, (B) pknB mutant and (C) fhaAB mutant. Cultures were grown on NE medium for 48 h and phosphoproteins subsequently enriched from cell extracts by affinity chromatography using a phosphoprotein purification kit (Qiagen). Samples were subsequently analysed by SDS‐PAGE, followed by detection of phosphoproteins with...