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The success of biological control of insect pests by parasitoids ultimately depends on effective host foraging by the agents, which involves multiple processes and various cues associated with hosts' habitat, host-associated symbionts and other microbial organisms, and/or hosts themselves. In general, parasitoid interactions with concealed hosts such as wood-boring beetles differ significantly from those that attack exposed hosts (eg surface-feeding caterpillars, aphids) as they must rely on a more complex hierarchy of cues to first locate hosts' microhabitats and then hosts for their reproduction. These differences influence the parasitoid's host-finding strategies, specificity, and their efficacy in suppressing their host populations. Here, we review the major steps in host finding by parasitoids of wood-boring beetles and synthesize current knowledge on the chemical, vibrational, visual, and other cues that mediate each stage of the process. We highlight how these cues operate across different spatial scales, interact with parasitoid morphology and behavior, and shape the success of biological control programs targeting economically important wood-boring pests. Finally, we identify key knowledges gaps and point to some future research directions aimed at improving the selection, deployment, and monitoring of parasitoid biological control agents in forest ecosystems.

Wild canids serve as definitive hosts for numerous Sarcocystis species infecting livestock and wildlife. However, species-level identification in free-ranging carnivores remains difficult, impeded by the morphological resemblance among the sporocysts of various parasite species. Intestinal mucosal scrapings from 40 wild canids: red fox (Vulpes vulpes, n = 8), gray fox (Urocyon cinereoargenteus, n = 6) and coyote (Canis latrans, n = 26) in Pennsylvania, USA, sampled in 2024, were tested for Sarcocystis sporocysts. Sporocysts were detected microscopically in intestinal homogenates digested in Chlorox in 3/6 (50%) gray foxes, 3/8 (37.5%) red foxes and 18/26 (69.2%) coyotes. PCR amplification was successful on 8/18 (44.4%) coyotes, 0/6 Gy foxes and 2/3 (66.6%) red foxes. Multi-locus genotyping was performed for the 18S rRNA, 28S rRNA, COI and ITS1 genetic markers, supporting identification of multiple species of Sarcocystis, including Sarcocystis albifronsi-like, S. cruzi, S. gjerdei-like, S. cristata/S. wenzeli-like and an additional undescribed, ungulate-associated Sarcocystis spp. Phylogenetic analysis confirmed clustering with reference sequences with strong support. This study demonstrates that wild foxes and coyotes serve as definitive hosts for multiple species of Sarcocystis, including Sarcocystis cruzi, which uses cattle as intermediate hosts and imposes significant economic burdens on cattle production. Moreover, these findings demonstrate that wild canids harbor diverse Sarcocystis spp., supporting their role in environmental dissemination and potential transmission at the wildlife-livestock interface.

Bacterial laccases are multicopper oxidase enzymes that are able to catalyze the oxidation reaction of phenolic and non-phenolic substrates followed by the reduction reaction of molecular oxygen to water as the only byproduct. It exhibits high stability under harsh conditions and can be produced recombinantly in various microbial hosts. Herein, we review recent advances in bacterial laccase research over the past decade, which focus on production technologies, protein engineering strategies, and diagnostic applications. We also discuss how synthetic biology has overcome historical limitations in heterologous expression and enabled industrial-scale production in hosts such as Escherichia coli and Bacillus subtilis. In addition, we analyzed how directed evolution, rational design, post-translational modifications, and computational modeling have enhanced the catalytic properties of laccases. In the final chapter, we evaluate the use of bacterial laccases as peroxidase alternatives for detecting clinical analytes like dopamine, uric acid, and glucose biosensing and point-of-care diagnostics. This review integrated more than 120 peer-reviewed papers and provides a comprehensive assessment of how bacterial laccases are transitioning from laboratory curiosities to practical biocatalysts in environmental monitoring, industrial processing, and medical diagnostics. We conclude the review by identifying remaining challenges and future research directions for realizing the full potential of these versatile enzymes.

Echinococcus multilocularis, which causes alveolar echinococcosis, can infect a wide range of hosts. Increasing interactions among wildlife, domestic animals, and humans may enhance the transmission risk in endemic areas. Surveillance of E. multilocularis in definitive hosts has relied on the post-mortem examination of the small intestine using the sedimentation and counting technique, with a recent shift toward non-invasive methods targeting fecal samples. However, host identification based solely on visual inspection of feces is often unreliable. Existing PCR-based methods are limited by complexity, low resolution, or a narrow range of target species. In this study, we developed a multiplex PCR assay targeting the mitochondrial 16S rRNA gene for simultaneous identification of 10 host species and evaluated its performance against a reference PCR assay. A total of 114 fecal samples, visually considered as fox-derived, were collected from roadsides in three areas in Hokkaido, Japan. Animal species were successfully identified in 106 samples (93.0%) using the newly developed multiplex PCR assay. Overall, foxes were the most common (74.6%), followed by cats (12.3%), dogs (5.3%), and raccoons (1.8%). The new assay showed almost perfect agreement with the reference method (κ = 0.94; 95% CI: 0.87-1; n = 114). Molecular identification revealed that 20.6% of samples were not derived from foxes, indicating that visual inspection is prone to identification errors. PCR screening detected E. multilocularis DNA in 34.2% of all samples. The positivity rate was 41.2% in foxes and 28.6% in cats. These findings highlight the importance of accurate host identification for reliable E. multilocularis surveillance. The developed multiplex PCR assay provides a rapid and robust approach to improve epidemiology accuracy and support effective control strategies.

Bats are natural reservoirs for over 4,400 viruses across 110 recognized viral families due to their high species diversity, long lifespans, and unique physiological adaptations. Their tolerance to viral infections without clinical disease stems from constitutive interferon-alpha (IFN-α) activity, high metabolic rates during flight, and tightly regulated inflammatory responses. Anthropogenic pressures including deforestation and urbanization intensify human-bat contact, facilitating viral spillover. Beyond direct transmission, bat-associated ectoparasites - ticks, bat flies, and mosquitoes - may serve as vectors and potential bridge hosts in viral maintenance and interspecies transmission, although the degree of vector competence varies considerably across taxa and viral systems. This review examines bat-virus interactions globally and in Türkiye, which hosts 39 bat species at the intersection of African and Eurasian faunal regions. Recent discoveries highlight the public health importance of bat-vector-virus networks; Jingmen tick virus (JMTV) detection in bat-associated ticks, tick salivary gland extract (SGE) supporting Kasokero virus (KASV) persistence, and Oita virus circulation for 50 years. This review presents the ecology of major bat-associated viral families, including Rhabdoviridae, Filoviridae, Coronaviridae, Nairoviridae, Flaviviridae, and Paramyxoviridae, while also discussing selected additional groups such as Reovirales, Iflaviridae, Togaviridae, and other emerging bat-associated viruses in relation to bat-vector interactions. Rather than excluding bats from ecosystems, comprehensive monitoring of bat-vector-virus networks through a One Health approach is critical for preventing zoonotic outbreaks in an era of climate change and increasing human-nature interaction.

Cyclodextrin (CD) derivatives bearing multicharged side chains exhibit enhanced host-guest binding, with higher selectivity and affinity compared with natural CDs, due to their deep cavities, polar binding sites and electrostatic interactions. To further understand the relationship between their structures and molecular recognition, molecular dynamics simulations were performed on a series of multicharged CD hosts with per-6-substituted side chains and their oppositely charged guests. In the case of rocuronium bromide (ROC) as the guest, umbrella sampling identified glutamic acid-substituted γ-CD as the host, exhibiting the strongest host-guest binding, with a free energy of -103.1 kJ mol-1, followed in descending order by aspartic acid-substituted γ-CD, glycine-substituted γ-CD, succinic acid-substituted γ-CD, sugammadex, and adamgammadex. Meanwhile, molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) analysis showed similar rankings, suggesting that electrostatic interactions play a dominant role in binding, while hydrophobic interactions, van der Waals forces, hydrogen bonding, and host-guest geometric complementarity act synergistically to stabilize the complexes. In addition, edrophonium@succinic acid-substituted β-CD and simvastatin@ammonium-substituted β-CD complexes were also evaluated, exhibiting binding free energies of -98.42 and -59.77 kJ mol-1, respectively. These findings provide mechanistic insights into CD derivative recognition and offer theoretical guidance for the rational design and experimental screening of high-affinity hosts.

Baculoviruses are highly diverse insect-specific DNA viruses that have coevolved with their lepidopteran hosts, often exhibiting high host specificity and geographic population structures. To investigate the genomic basis of host - associated divergence, we sequenced and analyzed the complete genome of a baculovirus isolated from symptomatic Eriogaster neogena larvae collected in Mongolia. The complete genome of this isolate, designated Malacosoma neustria nucleopolyhedrovirus Eriogaster neogena isolate (ManeNPV-Er), was sequenced and comparatively analyzed. Phylogenetic and pairwise K2P distance analyses based on lef8/lef9/polh were performed to evaluate its taxonomic relationship with other baculoviruses. Comparative genomic analysis revealed an overall nucleotide identity of 86.9% with Malacosoma neustria nucleopolyhedrovirus (ManeNPV-T2), which was isolated from a different host species (Malacosoma neustria) in Turkey. Despite their close taxonomic relationship, this low identity indicates substantial genomic divergence. Phylogenetic and pairwise K2P distance analyses based on lef8/lef9/polh confirmed their conspecific status. However, the corrected K2P distance suggests incipient divergence, which may require additional genomic and biological evidence to confirm. The significant genetic differentiation of ManeNPV-Er is potentially driven by the combined effects of adaptation to a distinct host and geographic isolation in a different region. Such divergence patterns are consistent with the parallel diversification commonly observed between baculoviruses and their lepidopteran hosts. Collectively, our findings expand the current understanding of baculovirus genomic diversity and provide new insights into how the interplay of host shift and geographic separation influences viral speciation.

Drosophila suzukii is a devastating global pest of soft-skinned fruits, yet its population dynamics in mountainous agricultural systems where cultivation extends across elevational gradients remain poorly understood. To address this gap, we conducted 2 years of intensive monitoring (2023-2024) in sweet cherry (Prunus avium) orchards at three elevations (1360-1910 m) in Wenchuan, China, characterizing adult population fluctuations and fruit infestation patterns. Adult population peaks were progressively delayed with increasing elevation, closely tracking local cherry phenology. Generalized linear mixed models revealed that adult abundance was positively associated with mean temperature and fruit maturity, with temperature effects strengthening significantly at higher elevations. Despite the later population buildup, infestation incidence at the highest site (1910 m) reached the 40% infestation threshold at a fruit maturity ratio 0.459 lower than at the lowest site (1360 m), indicating heightened susceptibility of high-elevation orchards. Field surveys identified 11 non-crop host species supporting D. suzukii reproduction before sweet cherry maturation. Notably, early-ripening Lonicera standishii at high elevations and Prunus pseudocerasus at low elevations served as critical population reservoirs. Interplanting with P. pseudocerasus advanced both the seasonal arrival of D. suzukii and the onset of sweet cherry damage by 5-10 d. These findings demonstrate that elevational gradients create asynchronous pest pressure, with high-elevation orchards facing disproportionately rapid infestation despite cooler temperatures. We provide an empirical basis for elevation-specific monitoring and management strategies such as the sterile insect technique, emphasizing targeted early-season intervention in non-crop hosts to mitigate spillover into commercial plantings.

Mosquitoes are generally regarded as the main vectors for many zoonotic diseases, capable of transmitting various diseases and causing significant public health burdens. In this study, a total of 232 Aedes albopictus mosquitoes were captured from Qingdao City, Shandong Province in the eastern part of China, and it was believed that a new subspecies of Rickettsia felis had been discovered. Genetic analysis indicated that the htrA gene has highest 99.29% identity to Rickettsia felis, an emerging human pathogen attracting global attention, predominantly sustained by fleas, mosquitoes and booklice. The 16S sequence of the strain had 100% of nucleotide similarity with Rickettsia sp. OnF11 gene for 16S rRNA. The gltA sequence had 98.77% similarity to both Candidatus Rickettsia senegalensis isolate and Candidatus Rickettsia senegalensis strain PU01-02. The groEL sequence had 99.42% similarity to Candidatus Rickettsia yingkouensis clone YK50. The ompB sequence had 99.42% similarity to Rickettsia hoogstraalii. In the phylogenetic tree based on concatenated nucleotide sequences of 16S, gltA, groEL, htrA and ompB genes, these strains were closely related to R. felis. Herein, it was named 'Candidatus Rickettsia felis subsp. laoshanensis'. Its ability to induce pathogenesis in both human and animal hosts is yet to be comprehensively determined.

SUMMARYThe skin harbors a diverse fungal community that contributes to both epidermal homeostasis and inflammatory disease. Historically, studies of cutaneous fungi focused primarily on opportunistic infections in immunocompromised hosts. Advances in sequencing technologies and metagenomic analyses have revealed that commensal yeasts of the skin microbiome likely influence host physiology and cutaneous disease severity. In this review, we summarize the current knowledge of host-fungal interactions at the skin epithelium, with particular emphasis on the yeast genera Malassezia and Candida. We discuss how fungal colonization shapes epidermal biology through direct interactions with keratinocytes and immune cells, highlighting fungal virulence factors such as secreted proteases and candidalysin, as well as host-sensing pathways. We further examine how these interactions contribute to inflammatory skin diseases, particularly atopic dermatitis and psoriasis, and how fungi participate in polymicrobial networks with bacteria and viruses to alter susceptibility to infection. Finally, we discuss how emerging therapeutic strategies change the fungal composition on skin. These advances suggest the importance of fungi as active regulators of skin immunity and emphasize key knowledge gaps that need to be addressed in future studies to better understand how they contribute to cutaneous diseases.

The connections between viruses and cancer have historically been studied in the context of viral oncogenesis. For decades, tumour virology has focused on oncogenic viruses such as hepatitis B virus, hepatitis C virus, human papillomavirus, Epstein-Barr virus, human T cell leukaemia virus type 1, Kaposi sarcoma-associated herpesvirus and Merkel cell polyomavirus, elucidating their oncogenic mechanisms, which include mutagenesis, chronic inflammation and immune evasion. However, the human virome is vast and complex, and this oncogenesis-centred view has overshadowed the possibility that certain viral exposures enhance antitumour immunity. Through millions of years of coevolution with animal hosts, the virome, consisting of diverse bacteriophages and eukaryotic viruses, including endogenous retroviruses, appear to have evolved strategies for coexistence that shape immune development and potentiate host surveillance pathways capable of recognizing and eliminating cancer cells. Non-oncogenic viruses can prime innate and adaptive immune responses, mimic tumour antigens and modulate the expression of immune checkpoints, as exemplified by the association of the enterovirus and rhinovirus CE1 epitope with protective liver cancer immunity. Moreover, endogenous retroviruses, naturally occurring oncolytic viruses and microbiome-associated phages may act as allies in cancer control. This Review explores the emerging evidence for viral anticancer immunity, its underlying mechanisms, and implications for a virome-guided framework for cancer prevention including new approaches to risk assessment, immune-based therapeutics and applications in low-resource settings.

The New World screwworm (NWS), Cochliomyia hominivorax, is an obligate ectoparasite whose larvae cause severe myiasis, leading to extensive tissue damage and potentially fatal outcomes in dogs if not promptly treated. Dogs play an important epidemiological role in maintaining and disseminating infestations, requiring rapid and effective therapeutic options. Fipronil (FIP) is an insecticide widely used for ectoparasite control with systemic efficacy after oral administration to different species, representing a promising alternative for treating canine myiasis. This study describes the development of molded FIP chewable tablets, the evaluation of its pharmacokinetics, and its clinical efficacy in dogs naturally infested by NWS larvae. For pharmacokinetic assessment, eight healthy dogs received a single dose (6 mg/kg) chewable tablet, and blood samples were collected at selected time points to determine plasma concentrations. To assess efficacy, eight dogs naturally infested with NWS larvae received the same dosage. Larvae expelled from hosts were collected over 24 h, after which remaining larvae were mechanically removed. The tablets met established quality control criteria. Following oral administration, FIP was rapidly absorbed, being detectable 30 min after treatment and reaching a maximum plasma concentration (Cmax) of 3126.5 ± 1269.5 ng/mL at 2.2 ± 0.94 h (Tmax). Clinically, larval expulsion increased progressively from 2 h onward, reaching 97.8% effectiveness within 24 h. No live larvae were observed in the lesions at the end of evaluation, resulting in 100% overall effectiveness. These findings demonstrate that the FIP chewable tablet is a viable alternative option for treating canine myiasis from NWS larval infestation.

Recent advances in microscopy techniques has uncovered unique aspects of flagella-driven motility in bacteria. A remarkable example is the discovery of flagellar wrapping, a phenomenon whereby a bacterium wraps its flagellum (or flagellar bundle) around its cell body and propels itself like a corkscrew, enabling locomotion in highly viscous or confined environments. For certain bacterial species, this flagellar-wrapping mode is crucial for establishing selective symbiotic relationships with their hosts. The transformation of a flagellum from an extended to a folded (wrapped) state is triggered by a buckling instability driven by the motor-generated torque that unwinds the helical filament. This study investigated this biologically inspired, novel buckling mechanism through a combination of macroscale physical experiments, numerical simulations, and scaling theory to reveal its underlying physical principles. Excellent quantitative agreement between experiments and numerical results showed that long-range hydrodynamic interactions are essential for accurate quantitative descriptions of the geometrically nonlinear deformation of the helical filament during wrapping. By systematically analyzing extensive experimental and numerical data, we constructed a stability diagram that rationalized the stability boundary through an elastohydrodynamic scaling analysis. Leveraging the scaling nature of this study, we compared our physical results with available biological data and propose that bacteria exploit motor-induced buckling instability to initiate their flagellar wrapping. Our findings indicate that this mechanically driven process is essential to bacterial-wrapping motility and, consequently, plays a critical role in symbiosis and infection.

Recent research has increasingly focused on machine learning (ML) models for early disease prediction, yet practical frameworks for integrating these models into clinical workflows remain limited. BIAlert is a microservices-based framework designed to operate as a real-time early-warning system for ML-driven disease prediction in hospitalised patients. It can be deployed remotely on physical or virtual servers and is composed of coupled microservices that communicate through Apache Kafka queues, using HL7 FHIR resources as the message format. The system comprises four core components: (1) the Connector, which ingests raw hospital data and converts it into standardised healthcare formats; (2) the Writer, which stores FHIR-formatted data in an internal database and triggers the prediction pipeline; (3) the Predictor, which hosts ML models and generates patient-specific alerts; and (4) the Model Evaluator, which supports prospective monitoring of model performance. Alerts are displayed through the BIAlert user interface and can also be integrated directly into the electronic health record (EHR). BIAlert is currently deployed and operating in real-time clinical settings in two hospitals, demonstrating its feasibility as a scalable and interoperable solution for ML-based clinical decision support.

Viruses shape microbial communities but remain underexplored in aquatic systems. Most studies target specific viruses as contamination indicators, while the potential of phages to reflect microbial dynamics is often overlooked. We designed and optimised two qPCR assays to quantify specific phages from the order Caudoviricetes-some of the most abundant in aquatic environments-infecting Mycobacterium, Rhodococcus and Gordonia spp. Major capsid protein (MCP) sequences were retrieved from the NCBI Viral Database and degenerate and non-degenerate primers, along with a TaqMan probe, were developed targeting the MCP gene. SYBR Green and TaqMan assays were optimised, validated using an MCP sequence and applied to samples from a drinking water treatment plant (DWTP), urban lakes and activated sludge. Both assays showed strong linearity with efficiencies of 95% (TaqMan) and 94% (SYBR Green). Viral gene copies decreased across the DWTP, indicating up to four-log phage removal during treatment. Phage counts in source water paralleled bacterial counts, especially in the cold season, suggesting a potential correlation between phages and bacterial hosts. Lake samples had higher phage concentrations (up to 106 copies/L), while only two wastewater treatment plants showed phage presence. These assays offer sensitive tools for monitoring phage abundance and microbial dynamics in freshwater environments.

Lignin valorization is critical to the economic viability of lignocellulosic biorefineries and could serve as an additional revenue stream for the pulp and paper industry. Emergent lignin-focused biomass pretreatment processes release a variety of aromatic monomers that could be directly upgraded into value-added aromatics for use as monomers, flavors, and fragrances. To date, most biological approaches for lignin valorization use a two-stage molecular disassembly&#x2192;targeted reconstruction strategy that leverages microbial funnels to route lignin monomers (>C6) into C2-C3 metabolic intermediates before building them back up into C6-C12 value-added chemicals. Here, we review the use of minimal enzyme cascades (<4 enzymes) that preserve the aromatic core for the atom-efficient transformation of ferulic acid (FA) and p-coumaric acid (pCA) into value-added products. We focus on FA/pCA because they are the primary aromatic monomers released from grassy lignin deconstruction and have been extensively upgraded in the literature, yielding over thirty value-added chemicals via minimal enzyme cascades. Opportunities in this space include artificial intelligence/machine learning-driven retro-biosynthetic approaches to predict minimal enzyme cascades for novel chemicals, coupled with cell-free expression systems for rapid validation prior to implementation in microbial hosts. Key challenges include aromatic toxicity to the microbial host, enzyme inhibition, poor heterologous expression of plant enzymes in microbes, and separation of aromatic production from lignin-derived aromatic feed streams. The high price point of value-added aromatics (>$15/kg), coupled with the low cost of lignin monomers (&#x223c;$4/kg), creates an opportunity for atom-efficient aromatic-to-aromatic lignin upgrading.

The aim of this study was to assess the role of leukotoxin in Mannheimia haemolytica on colonization dynamics in the nasopharynx and bacterial shedding in calves concurrently infected with bovine herpesvirus 1 (BHV-1). Eight calves were assigned to two treatment groups of four and housed in isolation rooms. After acclimation, BHV-1 was administered intranasally to both groups. On the same day, calves in one group received feed containing leukotoxin (LktA) deleted mutants of the M. haemolytica serotype (ST1) and ST6 strains. Five days post-BHV-1 exposure, this group was re-exposed to LktA mutants intranasally. On day six, both groups were intranasally inoculated with wild-type ST1 and ST6 parent strains, and the animals were euthanized on day 10. Results indicate that both ST1 and ST6 can establish high-level colonization in the nasopharynx of BHV-1 infected calves. LktA mutants exhibited approximately 10-fold lower nasopharyngeal colonization compared to their wild-type counterparts. The higher shedding levels observed in wild-type strains compared to LktA mutants suggested a clear advantage in spreading the infection to other susceptible animals. These findings provide valuable insight into the nature of M. haemolytica infection in bovine hosts. They also indicate that leukotoxin expression may contribute to the competitive fitness M. haemolytica strains, potentially influencing their adaptation within the host.

The maturation and infectivity of orthoflaviviruses is driven by interactions and structural changes of the two envelope proteins, prM and E, which are controlled by protonation and deprotonation events during the viral life cycle when the virus encounters acidic and neutral pH environments inside and outside the cell. Histidine residues act as sensors for these pH-induced conformational transitions, which differ between mosquito-borne and tick-borne orthoflaviviruses in some aspects. We identified six histidine residues that are conserved among the envelope proteins of mammalian tick-borne orthoflaviviruses, but not among those of mosquito-borne orthoflaviviruses. These residues might account for some of the structural differences observed between these two orthoflavivirus groups. We therefore conducted a mutational analysis by replacing each of the conserved histidine residues with alanine and determined the effect of these mutations on the maturation and infectivity of tick-borne encephalitis virus (TBEV). One of the histidine residues (H208, located in an insert unique to mammalian tick-borne orthoflaviviruses at the prM-binding site in E) was shown to be an important determinant of efficient prM cleavage. In line with recent findings regarding the infectivity of immature tick-borne orthoflaviviruses, this mutant was only slightly less infectious than the mature wild-type virus. The presence of histidine residue 208 appears to be linked to the particular requirements of the complex ecological life cycle of TBEV and likely reflects an evolutionary adaptation to the specific interactions of the virus with mammalian hosts and/or tick vectors.