Biology subjects

Evans, J. D.

Publications and source records attributed to Evans, J. D..

At least 19 recordsLinked to original sources

bioRxiv2025

Insights from U.S. beekeeper triage surveys following unusually high honey bee colony losses 2024-2025

In January of 2025, U.S. commercial beekeepers reported unusually high honey bee colony losses as they prepared colonies for almond pollination. Two industry groups launched nationwide surveys to document colony losses between June 2024 and March 2025 across all scales of beekeeping. This study analyzes these survey data to assess colony losses, estimate financial impacts, and identify correlations with beekeeper management practices and geographical locations. Unlike past surveys, commercial beekeepers experienced more severe losses than smaller-scale beekeepers during this period. Respondents, managing over half of U.S. colonies, most frequently cited Varroa mites as the cause for their losses. Varroa mites were followed by pesticides and pathogens in the case of commercial beekeepers and by queen failure and weather in the case of smaller-scale beekeepers. Although Varroa was the most frequently cited cause, losses did not significantly differ between users and non-users of amitraz, suggesting that rising amitraz resistance alone does not explain observed trends. Differences in protein and carbohydrate feeding frequencies also played a role in net losses. While colony loss rates and financial concern varied widely among respondents, commercial beekeepers understandably showed higher sensitivity to financial impacts, with concerns increasing linearly with loss severity. This study highlights the value of beekeeper surveys which, alongside direct analyses of bee samples and longitudinal studies, help identify effective management strategies and environmental risks. Such insights are crucial for addressing the leading causes of colony losses on a national scale, and ultimately aid in safeguarding honey bee health, pollination services, and agricultural production. HighlightsO_LIUnprecedented honey bee colony losses C_LIO_LIIndications of disease stress C_LIO_LIHigh economic pain for commercial beekeepers and growers C_LI

ecology↗

bioRxiv2025

Possible origins of kombucha in spontaneous fermentation

Although the microbial composition and functional attributes of kombucha have been extensively studied, the origins and mechanisms of the formation of their biofilm (Symbiotic Culture of Bacteria and Yeasts, or SCOBY) remain speculative. Based on historical reports and the concept of community coalescence, this study establishes a proof-of-concept, demonstrating how a kombucha-like biofilm can form spontaneously from microbes associated with plants, insects, and humans in a sweetened tea medium. Metagenomic analyses revealed microbial dynamics during fermentation, uncovering shifts in community composition driven by acetic acid bacteria, lactic acid bacteria, and yeasts. Comparative analyses with existing fermented beverages demonstrated microbial similarities to kombucha metagenomes. Pangenomic analyses focused on Fructobacillus evanidus, a species present in both the bee microbiome and our spontaneous fermentation. The MAGs of F. evanidus from the fermented beverage showed evidence of genetic streamlining, characterized by the loss of genes essential for survival in shifting and highly competitive environments, such as the bee gut, and adaptation to the more stable conditions of fermentation. This study offers insights into the origins of kombucha, integrating historical, microbiological, ecological and evolutionary perspectives to answer the question Is this a kombucha?, and gesturing toward further physical, chemical and sensory dimensions that could be explored.

microbiology↗

bioRxiv2025

Viruses and vectors tied to honey bee colony losses

Commercial beekeepers in the US reported severe colony losses early in 2025, as colonies were being staged for their critical role in the almond pollination season in California. Average reported losses since the preceding spring exceeded 60%, with substantial variation among operations. Many colonies were still actively collapsing in January, 2025, when pooled and individual samples were collected then screened for levels of known honey bee pathogens and parasites. Deformed wing virus strains A and B, along with Acute bee paralysis virus, were found at unusually high levels, either in pooled colony samples or in individual bees exhibiting shaking behaviors and morbidity. Differences between these two analyses suggest that direct collections of morbid bees provide a superior diagnostic for causal viruses, a suggestion borne out by confirmation of symptoms and morbidity following isolation and new inoculations. Since these viruses are known to be vectored by parasitic Varroa mites, mites from collapsed colonies were in turn screened for resistance to amitraz, a critical miticide used widely by beekeepers. Miticide resistance was found in all collected Varroa, underscoring the urgent need for new control strategies for this parasite. While viruses are a likely end-stage cause of colony death, other stressors such as nutritional stress and agrochemicals may have also played significant roles.

ecology↗

bioRxiv2025

Visualizing the Chronicle of Multiple Cell Fate using a Near-IR Dual-RNA/DNA-Targeting Probe

Early detection and late-stage cell fate assessment are key factors to develop therapeutic strategies, although current methods cannot capture early responses or distinguish multiple injury states, especially in UV-vis-sensitive cells. Here, we introduce a method to simultaneously detect variations in RNA and DNA under near-infrared photoexcitation. Utilizing a pyrazinacene-based probe (TEG8-N14), we unexpectedly achieved discrimination of multiple cell states, including apoptosis, necrosis, necroptosis, and senescence, based on RNA-DNA changes. Specifically, TEG8-N14 selectively stains necrotic cells in live samples, while after fixation, it allows detection of ultra-early senescence in UV-vis-sensitive cells, providing approximately two-fold greater informational content than existing RNA or DNA fluorophores. These findings break current imaging barriers by enabling comprehensive visualization of single-cell fate histories without being affected by UV-vis or genetic manipulation.

bioengineering↗

bioRxiv2025

Chromosome-level genome assembly of Protandrena (Anthemurgus) passiflorae (Hymenoptera: Andrenidae), a host-plant specialist bee

The passion flower bee, Protandrena (Anthemurgus) passiflorae (Robertson) is a monolectic, host-plant specialist of the passionflower plant Passiflora lutea L. Using a single adult male individual, we generated long-read PacBio HiFi, HiC, and short-read RNA sequencing data to build a well-annotated, chromosome-level genome assembly for this species. The final nuclear genome is 249 Mb with 150x coverage and with most of the genome scaffolding into 12 chromosomes. The scaffold N50 is 21.4 Mb and the genome has a Benchmarking Universal Single-Copy Ortholog (BUSCO) score of 97.2% for 5991 hymenopteran genes. BRAKER3 annotation of the genome identified 12,098 genes and 15,353 total transcripts and found that 20.27% of the genome is made up of repetitive elements. We resolved a mitochondrial genome of 12.7 kb. The P. passiflorae genome represents one of only a few published andrenid bee genomes and one of the first monolectic bees. This new high-quality genome will serve as a valuable resource for investigating the genomic basis of specialization and for providing a useful resource for studying pollinator health and conservation.

genomics↗

bioRxiv2024

Repeated shifts in sociality are associated with fine-tuning of highly conserved and lineage-specific enhancers in a socially flexible bee

Comparative genomic studies of social insects suggest that changes in gene regulation are associated with evolutionary transitions in social behavior, but the activity of predicted regulatory regions has not been tested empirically. We used STARR-seq, a high-throughput enhancer discovery tool, to identify and measure the activity of enhancers in the socially variable sweat bee, Lasioglossum albipes. We identified over 36,000 enhancers in the L. albipes genome from three social and three solitary populations. Many enhancers were identified in only a subset of L. albipes populations, revealing rapid divergence in regulatory regions within this species. Population-specific enhancers were often proximal to the same genes across populations, suggesting compensatory gains and losses of regulatory regions may preserve gene activity. We also identified 1182 enhancers with significant differences in activity between social and solitary populations, some of which are conserved regulatory regions across species of bees. These results indicate that social trait variation in L. albipes is driven both by the fine-tuning of ancient enhancers as well as lineage-specific regulatory changes. Combining enhancer activity with population genetic data revealed variants associated with differences in enhancer activity and identified a subset of differential enhancers with signatures of selection associated with social behavior. Together, these results provide the first empirical map of enhancers in a socially flexible bee and highlight links between cis-regulatory variation and the evolution of social behavior.

evolutionary biology↗

bioRxiv2024

Somy evolution in the honey bee infecting trypanosomatid parasite, Lotmaria passim

Lotmaria passim is a ubiquitous trypanosomatid parasite of honey bees nestled within the medically important subfamily Leishmaniinae. Although this parasite is associated with honey bee colony losses, the original draft genome--which was completed before its differentiation from the closely related Crithidia mellificae--has remained the reference for this species despite lacking improvements from newer methodologies. Here we report the updated sequencing, assembly, and annotation of the BRL type strain (ATCC PRA-422) of Lotmaria passim. The nuclear genome assembly has been resolved into 31 complete chromosomes and is paired with an assembled kinetoplast genome consisting of a maxicircle and 30 minicircle sequences. The assembly spans 33.7 Mb and contains very little repetitive content, from which our annotation of both the nuclear assembly and kinetoplast predicted 10,288 protein-coding genes. Analyses of the assembly revealed evidence of a recent chromosomal duplication event within chromosomes 5 and 6 and provides evidence for a high level of aneuploidy in this species, mirroring the genomic flexibility employed by other trypanosomatids as a means of adaptation to different environments. This high-quality reference can therefore provide insights into adaptations of trypanosomatids to the thermally regulated, acidic, and phytochemically rich honey bee hindgut niche, which offers parallels to the challenges faced by other Leishmaniinae during the challenges they undergo within insect vectors, during infection of mammals, and exposure to antiparasitic drugs throughout their multi-host life cycles. This reference will also facilitate investigations of strain-specific genomic polymorphisms, their role in pathogenicity, and the development of treatments for pollinator infection.

genomics↗

bioRxiv2024

Ripened plant-based cheese analogs in Europe: nutritional and microbial profiles

Plant-based cheese analogs have emerged as a novel global market trend driven by sustainability concerns for our planet. This study examines eleven soft ripened plant-based cheese analogs produced in Europe, primarily with bloomy rinds and cashew nuts as the main ingredient. First, we focused on exploring the macronutrients and salt content stated on the labels, as well a detailed fatty acid analysis of the samples. Compared to dairy cheeses, plant-based cheeses share similarities in lipid content, but their fatty acid profiles diverge significantly, with higher ratio of mono- and polyunsaturated fatty acids such as oleic and linoleic acids. We also investigated the microbiota of these analog products, employing a culture-dependent and -independent approaches. We identified a variety of microorganisms in the plant-based cheeses, with Lactococcus lactis and Leuconostoc mesenteroides being the dominant bacterial species, and Geotrichum candidum and Penicillium camemberti the dominant fungal species. Most of the species characterized are similar to those present in dairy cheeses, suggesting that they have been inoculated as culture starters to contribute to the sensorial acceptance of plant-based cheeses. However, we also identify several species that are possibly intrinsic to plant matrices or originate from the production environment, such as Pediococcus pentosaceus and Enterococcus spp. This coexistence of typical dairy-associated organisms with plant associated species highlights the potential microbial dynamics inherent in the production of plant-based cheese. These findings will contribute to a better understanding of plant-based cheese alternatives, enable the development of sustainable products, and pave the way for future research exploring the use of plant-based substrates in the production of cheese analogues.

microbiology↗

bioRxiv2024

Evaluation of efficacy of formic acid and thermal remediation for management of Tropilaelaps and Varroa mites in central Thailand

The western honey bee, Apis mellifera, faces a new threat from the spread of parasitic Tropilaelaps (Tropi) mites, specifically T. mercedesae, which adds additional complexity to an apicultural landscape heavily impacted by Varroa destructor. In this study conducted in central Thailand, we investigated the efficacy of two methods of applying formic acid and a thermal remediation technique in controlling Tropi mites and Varroa, focusing our attention on the reproductive stage of the mites which is restricted to capped brood cells. Results revealed that both formic acid treatments (Formic Pro and liquid formic acid) demonstrated an immediate and substantial reduction in live Tropi and Varroa populations, maintaining near-zero levels for the 3- week duration of the study. In contrast, thermal remediation, employing heating pads, exhibited a more gradual decline, achieving an 85.42% reduction in Tropi mites and a 92.33% reduction in Varroa mites by week three. Notably, heat-treated colonies experienced an unexpected resurgence in mite populations during week two. The findings contribute valuable insights into potential strategies for mitigating the threat of Tropi mites and highlight the urgency of further research to safeguard global honey bee populations.

zoology↗

bioRxiv2024

Food Fermentation in Space Is Possible, Distinctive, and Beneficial

Space exploration is expanding, which demands new technologies and enables new scientific questions. Food, as a bridge between disciplines, can bring these fundamental and applied goals together. Here we investigate whether food fermentation in space is possible, and if so, how it compares with fermentation on Earth. We fermented a miso, a traditional Japanese condiment, on the International Space Station over 30 days, and compared it with two earthbound controls. Using a specially-built environmental sensing box, we gathered metadata for temperature, relative humidity, pressure, and radiation. We analyzed the three misos with shotgun metagenomics to investigate the microbial communities composition and safety; whole genome sequencing to investigate the mutation rate of Aspergillus oryzae; untargeted metabolomics to quantify aromatic compounds, amino acids and organic acids; colorimetry to quantify color; and sensory analysis to describe the misos flavours and quantify liking and sensory difference. Across these datasets, we found that overall, the space miso is recognizable as a miso, suggesting fermentation in space is possible. We also found certain differences in the space miso: specifically the presence of Bacillus velezensis, a higher mutation rate of A. oryzae, higher attributions of roasted and nutty flavours, and the most different sensory impression. Taken together, these observations suggest unique features of the space environment--what we might call space terroir--which could be harnessed to create more flavorful, nourishing foods for long-term space missions and to address fundamental questions about the biology of novel environments. Significance StatementOur study presents, to our knowledge, the first time a food product has been fermented in space. We demonstrate that fermentation in space is possible with safe and successful results, a proof of concept that offers fermentation as a new tool for space research and future long-term space exploration missions. We also document how the space environment shapes the fermentation process in unique ways, suggesting a space terroir. These findings on the feasibility and novelty of fermentation in space open up directions for further multidisciplinary research across science, health, systems design, and society and culture.

microbiology↗

bioRxiv2024

Nano Colonies: Rearing honey bee queens and their offspring in small laboratory arenas

Honey bees create complex societies of self-organized individuals in intricate colonies. Studies of honey bees are carried out in both the field and the laboratory. However, field research is encumbered by the difficulties of making reliable observations and environmental confounders. Meanwhile, laboratory trials produce data that are not field realistic as they lack key characteristics of a natural colony. Additionally, advances in honey bee research have been hindered without reliable methodology to rear queens in the laboratory. Here we provide a new system to reliably produce queens and worker brood in the laboratory and describe how this system fits with artificial insemination of queens as a step towards a continuous self-contained source of bees. The process creates a bridge between field research and laboratory trials and provides a secure system for contagious or regulated elements while maintaining many of the intrinsic characteristics of a honey bee colony.

zoology↗

bioRxiv2023

High temperatures augment inhibition of parasites by a honey bee gut symbiont

Temperature affects growth, metabolism, and interspecific interactions in microbial communities. Within animal hosts, gut bacterial symbionts can provide resistance to parasitic infections. Infection can also be shaped by host body temperature. However, the effects of temperature on the antiparasitic activities of gut symbionts have seldom been explored. The Lactobacillus-rich gut microbiota of facultatively endothermic honey bees is subject to seasonal and ontogenetic changes in host temperature that could alter the effects of symbionts against parasites. We used cell cultures of a Lactobacillus symbiont and an important trypanosomatid gut parasite of honey bees to test the potential for temperature to shape parasite-symbiont interactions. We found that symbionts showed greater heat tolerance than parasites and chemically inhibited parasite growth via production of acids. Acceleration of symbiont growth and acid production at high temperatures resulted in progressively stronger antiparasitic effects across a temperature range typical of bee colonies. Consequently, the presence of symbionts reduced both peak growth rate and heat tolerance of parasites. Results suggest that the endothermic behavior of honey bees could potentiate the effectiveness of gut symbionts that limit parasites ability to withstand high temperature, implicating thermoregulation as a reinforcer of core symbioses and possibly microbiome-mediated antiparasitic defense. IMPORTANCETwo factors that shape the resistance of animals to infection are body temperature and gut microbiota. However, temperature can also alter interactions among microbes, raising the question of whether and how temperature changes the antiparasitic effects of gut microbiota. Honey bees are agriculturally important hosts of diverse parasites and infection-mitigating gut microbes. They can also socially regulate their body temperatures to an extent unusual for an insect. We show that high temperatures found in honey bee colonies augment the ability of a gut bacterial symbiont to inhibit growth of a common bee parasite and reduce the parasites ability to grow at high temperatures. This suggests that fluctuations in colony and body temperatures across life stages and seasons could alter the protective value of bees gut microbiota against parasites, and that temperature-driven changes in gut microbiota could be an underappreciated mechanism by which temperature-- including endothermy and fever-- alters animal infection.

ecology↗

bioRxiv2022

Host-driven temperature dependence of viral infection in honey bees

The temperature dependence of infection reflects changes in the performance of parasites and hosts. High temperatures (i.e., fever) often mitigate infection by favoring heat-tolerant hosts over heat-sensitive parasites. Honey bees exhibit an endothermic, colony-level temperature regulation that is exceptional among insects and favors resistance to several parasites. However, proliferation of viruses is heavily host-dependent, suggesting that viral infection could be linked to--not threatened by--optimum host function. To understand how temperature-driven changes in performance of viruses and hosts shape virus proliferation, we compared the temperature dependence of isolated viral enzyme activity, three honey bee traits, and infection of honey bee pupae. Viral enzyme activity varied by <2-fold over a >30 {degrees}C interval that spanned the temperatures typical of ectothermic insects and honey bees. In contrast, metrics of honey bee performance peaked at high ([≥] 35 {degrees}C) temperatures and were highly temperature-sensitive, with respiration varying 8-fold over a 20 {degrees}C interval and successful development requiring a narrow 8 {degrees}C temperature range. Although these results suggested that hosts would gain a relative advantage over viruses with increasing temperature, the temperature dependence of pupal infection matched that of pupal development, falling only near pupaes upper thermal limits. Our results reflect the host-dependent nature of virus proliferation, suggesting that infection is accelerated--not curtailed--by optimum host function, contradicting predictions of infection based on the relative performance of parasites and hosts, and suggesting tradeoffs between infection resistance and host survival. Despite a 98% reduction in infection at the upper end of the colony temperature range, the narrow thermal safety margin for honey bee development might preclude the effectiveness of fever for controlling viruses.

ecology↗

bioRxiv2022

Kleptocytosis: A Novel Parasitic Strategy for Accelerated Reproduction via Host Protein Stealing in Varroa destructor

Varroa destructor must produce mature offspring within the inflexible nine-day window framing the pupal development of their honey bee host. Missing this deadline renders the foundress mites fitness zero, establishing evolutionary pressure to accelerate reproduction and development. Through micro-computed tomography and modeling Varroas energy budget, we found each egg grows to constitute [~]18% of the foundresss body volume in 30 hours, yet accounts for less than 10% of her energy usage. We hypothesized that this small energy investment is a successful strategy because of Varroas long-ignored ability to traffic intact host proteins. Through gel electrophoresis, concomitant immunodetection, and MS/MS, we detected several intact, bee-derived proteins in mite eggs, including metamorphic proteins (hexamerins) and egg-yolk precursors (vitellogenin and apolipophorin) which likely reduce the parasites direct reproductive investment. We then expressed recombinant Halotag labelled Apis vitellogenin to determine the route conveying exogenous proteins into the mites oocyte. We detected fluorescent vitellogenin in the lyrate organ and observed a tube-like extension of the lyrate organ connecting to the ovum, likely providing an avenue for intact host proteins. Finally, we tested the hypothesis that exogenous proteins maintain functionality in the parasite. Varroa metamorphose despite their inability to produce hexamerins, critical metamorphic proteins. Through label-free quantification of proteins in metamorphosing mites, we observed a hexamerin depletion pattern consistent with usage as a metamorphic amino acid reservoir. We describe this process as "kleptocytosis," denoting movement of stolen intact macromolecules from host to a parasite cell. Given their fixed developmental timeline, this pathway presents a promising target for novel Varroa management strategies. Significance StatementGlobal honey bee health is threatened by the parasitic mite Varroa destructor; its success due in part to its rapid reproduction and accelerated development. By combining biological modeling, micro-computed tomography, fluorescence imaging, and quantitative proteomics, we show that Varroa siphon intact, ostensibly functional host proteins conveying them directly to their oocyte. This avoids the energetically inefficient process of digesting and reconstructing ingested proteins and affords the capacity to utilize proteins that it does not produce de novo facilitating rapid reproduction and accelerated development. We call this process "kleptocytosis," and identify anatomical adaptations which apparently facilitate protein movement. This work exposes a new target in Varroas physiology, providing a promising direction for more effective management strategies.

zoology↗

bioRxiv2022

Oversharing by honey bees and the spread of viruses

Deformed wing virus (DWV) is an emerging insect pathogen efficiently transmitted through communicable and vector-borne routes with Apis mellifera. Continual transmission of DWV between hosts and vectors is required for maintenance of the pathogen within the population, and this vector-host-pathogen system offers unique disease transmission dynamics for pathogen maintenance between vector and a social host. In a series of experiments, we study how vector-vector, host-host and host-vector transmission routes maintain DWV in a honey bee population. We found co-infestations on shared hosts allowed for movement of DWV from mite to mite. Additionally, two social behaviors of the honeybee, trophallaxis and cannibalization of pupae, provide routes for communicable transmission from bee to bee. Communicable circulation of the virus solely amongst hosts was then shown to act as a reservoir of DWV for naive Varroa to acquire and subsequently vector the pathogen. Our findings illustrate communicable transmission between hosts can maintain and influence the future acquisition and vectoring of a pathogen by a vector. There are a handful of other infectious diseases, both zoonotic and which impact human health, that have potentially similar transmission dynamics.

pathology↗

bioRxiv2022

The vectoring competence of the mite Varroa destructor for Deformed wing virus of honey bees is highly dynamic and affects survival of the mite.

The ectoparasitic mite, Varroa destructor and the viruses it vectors, including types A and B of Deformed wing virus (DWV), pose a major threat to honey bees, Apis mellifera. Analysis of 256 mites collected from the same set of colonies on five occasions from May to October 2021 showed that less than a half of them, 39.8% (95% confidence interval (CI): 34.0 - 46.0%), were able to induce an overt-level DWV infection with more than 109 viral genomes per bee in the pupa after 6 days of feeding, with both DWV-A and DWV-B being vectored at similar rates. To investigate the effect of the phoretic stage on the mites ability to vector DWV, the mites from two field collection events were divided into two groups, one of which was tested immediately for their infectiveness, and the other was kept with adult worker bees in cages for 12 days prior to testing their infectiveness. We found that while 39.2 % (95% CI: 30.0 - 49.1%) of the immediately tested mites induced overt-level DWV infections, 12-day phoretic passage significantly increased the infectiousness of mites to 89.8% (95% CI: 79.2 - 95.6%). It is likely that Varroa mites that survive brood interruptions in field colonies are increasingly infectious. We found that mite lifespan was significantly affected by the type of DWV it transmitted to pupae. The mites, which induced overt DWV-B but not DWV-A infection had an average lifespan of 15.5 days (95% CI: 11.8 - 19.2 days), which was significantly shorter than those of the mites which induced overt DWV-A but not DWV-B infection, with an average lifespan of 24.3 days (95% CI: 20.2 - 28.5), or the mites which did not induce high levels of DWV-A or DWV-B, with an average survival of 21.2 days (95% CI: 19.0 - 23.5 days). The mites which transmitted high levels of both DWV-A and DWV-B had an intermediate average survival of 20.5 days (95% CI: 15.1 - 25.9 days). The negative impact of DWV-B on mite survival could be a consequence of the ability of DWV-B, but not DWV-A to replicate in Varroa mites.

microbiology↗

bioRxiv2022

Promiscuous feeding across multiple honey bee hosts amplifies the vectorial capacity of Varroa destructor

Varroa destructor is a cosmopolitan pest and leading cause of colony loss of the European honey bee. Historically described as a competent vector of honey bee viruses, this arthropod vector is cause for the global pandemic of Deformed wing virus, now endemic in honeybee populations. Our work shows viral spread is driven by Varroa actively switching from one adult bee to another as they feed. Assays using fluorescent microspheres were used to show the movement of fluids in both directions between host and vector when Varroa feed. Therefore, Varroa could be in either an infectious or naive state dependent upon the disease status of their host. We tested this and confirm that the relative risk of a Varroa feeding was dependent on the infectiousness of their previous host. Varroa exhibit remarkable heterogeneity in their host switching behavior, with some Varroa switching infrequently while others switch at least daily. As a result, relatively few of the most active Varroa parasitize the majority of bees. This multiple feeding behavior has analogs in vectorial capacity models of other systems, where promiscuous feeding by individual vectors is a leading driver of vectorial capacity. We propose that the honeybee-Varroa relationship offers a unique opportunity to apply principles of vectorial capacity to a social organism, as virus transmission is both vectored and occurs through multiple host-to-host routes common to a crowded society.

animal behavior and cognition↗

bioRxiv2022

Culture and genomic analysis of Arsenophonus apicola sp. nov. isolated from the honeybee Apis mellifera

The genus Arsenophonus has been traditionally considered to be comprised of heritable bacterial symbionts of arthropods. Recent work has reported a microbe related to the type species A. nasoniae as infecting the honey bee, Apis mellifera. The association was unusual for members of the genus in that the microbe-host interaction arose through environmental and social exposure rather than vertical transmission. In this study, we describe the in vitro culture of ArsBeeUS, a strain of this microbe isolated from A. mellifera in the USA. The 16S rRNA sequence of the isolated strain clearly indicates it falls within the genus Arsenophonus. Biolog analysis indicates the bacterium has a restricted range of nutrients that support growth. In vivo experiments demonstrate the strain proliferates rapidly on injection into A. mellifera hosts. We further report the closed genome sequence for the strain. The genome is 3.3 MB and 37.6% GC, which is smaller than A. nasoniae but larger than the genomes reported for non-culturable Arsenophonus symbionts. The genome is complex, with 6 plasmids and 11 predicted intact phage elements, but notably less complex than A. nasoniae. With 92% average nucleotide identity (ANI) to the type strain A. nasoniae, the ArsBeeUS strain isolated is clearly distinct from the type species, and we propose the name Arsenophonus apicola sp. nov. (CECT 30499; LMG 32504).

microbiology↗