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As one of the core framework proteins of nuclear pore complex (NPC), nucleoporin Nupl70 acts as a structural adapter between the nucleolus and nuclear pore membrane and maintains the stability of NPC structure through interaction with other proteins. In this study, we identified a Nup170 protein in the microsporidian Nosema bombycis for the first time and named it as NbNup170. Secondary structure prediction showed that the NbNup170 contains α-helices and random coils. The three-dimensional structure of NbNup170 is elliptical in shape. Phylogenetic analysis based on the Nup170 and homologous sequences showed that N. bombycis clustered together with Vairimorpha ceranae and Vairimorpha apis. The immunofluorescence localization results showed that the NbNup170 was located on the plasma membrane of the dormant spore and transferred to the surface of sporoplasm in a punctate pattern when the dormant spore has finished germination, and that NbNup170 was distributed on the nuclear membrane and both sides of the nuclei of early proliferative phase, and only on the nuclear membrane during sporogonic phase in the N. bombycis. qPCR analysis showed that the relative expression level of NbNup170 maintained at a low level from 30 to 78 h post-infection with N. bombycis, then reached the highest at 102 h, while that of NbNup170 was repressed at a very low level throughout its life cycle by RNA interference. These results suggested that NbNup170 protein is involved in the proliferative phase and active during the sporogonic phase of N. bombycis.

The gypsy moth, Lymantria dispar, is one of the most important pests of deciduous trees in Europe, occurring in all environmental zones of Europe except the Alpine North and part of the Boreal zone. The gypsy moth fungal pathogen Entomophaga maimaiga, originally from Asia, was imported from the USA and released in Bulgaria, in 1999–2000. Spread of E. maimaiga in Central Europe was documented from 2011 to 2013, but this pathogen was only detected as far north as Slovakia. Collections of dead L. dispar larvae in 2019 (but not 2018), in areas of both sporadic and cyclic L. dispar outbreaks, resulted in the first detections of E. maimaiga in the Czech Republic. Lymantria dispar larvae were exposed to soil from oak forests in 2014–2018, but only infection by the gypsy moth nucleopolyhedrovirus (LdNPV) and the microsporidium Vairimorpha (= Nosema) lymantriae was detected. At most localities in the cyclic outbreak area, in 2017 the first defoliations of a new outbreak cycle occurred and the numbers of gypsy moth egg masses began to increase, so the calculated duration of approximately 13 years from outbreak to outbreak in the Czech Republic was verified.

Nosema leptinotarsae Lipa, 1968 is a microsporidian pathogen of the Colorado potato beetle, Leptinotarsa decemlineata Say. (Coleoptera: Chrysomelidae). To determine the phylogenetic status of N. leptinotarsae, the 16S SSU rRNA gene was sequenced (GenBank Accession No. MN841279) and compared phylogenetically against 21 microsporidian 16S SSU rRNA sequences using neighbour-joining and maximum-parsimony methods. The per cent identities of the N. leptinotarsae and other members of the Nosema–Vairimorpha clade ranged from 78.1 to 98.5%. Pairwise phylogenetic distances between the N. leptinotarsae and other species ranged from 0.009 to 0.320. Phylogenetic analysis shows clearly that N. leptinotarsae is a member of the Vairimorpha clade rather than the Nosema clade. The sequence divergence and morphological traits separated the N. leptinotarsae from other species in the Vairimorpha complex. As a result, a new assignment of Vairimorpha leptinotarsae comb. nov. has been implemented for N. leptinotarsae according to the phylogenetical positioning in the present study.

Microsporidia are intracellular fungal parasites and they are the most common pathogens for sericulture. Microsporidian sp. can cause pebrine, a dreadful disease and lead to destructive disorder in Muga silkworm, Antheraea assamensis Helfer by vertical and horizontal transmission. This disease is the key factor obstructing the developmental progress of Muga culture in India. Nevertheless, molecular identification and characterization of pathogen associated with pebrine disease in A. assamensis is not yet established. Insect bioassay studies revealed that microsporidian infection in Muga silkworm, A. assamensis Helfer significantly reduced (P

Microsporidia are unique fungi that exist as obligate intracellular parasites. Approximately 40% of the known microsporidian strains infect various insects. Due to their high host specificity, microsporidia have potential use as powerful biological pesticides. Here, we analyzed microsporidian strains isolated from the common cutworm, Spodoptera litura Fabricius (Lepidoptera: Noctuidae) of Japan and Taiwan, which is considered a pest insect. Two experiments were performed: a comparison of spore size and a phylogenetic analysis using small subunit ribosomal RNA gene sequencing. We then estimated the flight routes of S. litura by using the phylogenetic relationships of the isolated microsporidian strains as a marker. An analysis of spore size indicated that the test strains comprised three groups: Pleistophora, Nosema or Vairimorpha, and Trachipleistophora or Vavraia. The results of the phylogenetic analysis suggested a classification into five genera, including Vavraia. The genus Vavraia was first detected from lepidopteran insects in Japan. We estimated the sources and flight routes of S. litura using phylogenetic data for the genera Nosema and Trachipleistophora. In this study, we used microsporidia as a novel marker to estimate sources and flight routes of S. litura from Ogasawara and Southern China to mainland Japan, demonstrating the usefulness of this approach.

Nosemosis caused by Vairimorpha ceranae is one of the most important threats to honeybee colonies worldwide. This study aimed to determine the prevalence and intensity of Vairimorpha infection in different types of colonies and locations in Iran. In October 2017 and May 2018, 376 colonies from 97 apiaries were selected for each month according to a randomly clustered design. By considering 3–5 colonies for each apiary, 20 adult bees as pooled samples were collected from each colony. In microscopic analysis, 46.52% and 46.1% of samples in May and October showed Vairimorpha spores, respectively. The infection intensities in May and October were 5.94 ± 0.19 (× 106) and 5.86 ± 0.23 (× 106) spores/bee in a pooled sample, respectively. The mean infection intensity ranged from 1.8 to 12.5 (× 106) spores/bee. Statistically, there were no significant differences in the prevalence and intensity of V. ceranae infection between May and October samples. No significant differences were found among the prevalence rates of infection in the types of colonies; however, the intensity was significantly higher in migratory and mountainous colonies in May and only in migratory colonies in October. There was a significant correlation between the prevalence and intensity of V. ceranae infection (r2 = 0.695). PCR analysis showed that the samples were only infected with V. ceranae. No intraspecific variation to V. ceranae was found by direct sequencing of the amplified fragment of 16S rRNA. The obtained sequence was mainly 100% similar to those of V. ceranae isolates from European countries.

Made available in DSpace on 2021-06-25T11:01:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Microsporidia are naturally occurring fungal-related parasites that can infect nearly all animal hosts, but their biocontrol potential of insect pests is routinely overlooked in agriculture and forestry. This research brings the first report describing the natural occurrence of a microsporidium causing disease in field-collected populations of the invasive eucalyptus snout beetle, Gonipterus platensis (Coleoptera: Curculionidae), a major destructive pest of eucalyptus plantations in Brazil. Adult beetles were collected during field surveys in commercial eucalyptus plantations in southern Brazil to be examined and dissected with typical symptoms to verify presence of microsporidian spores in haemolymph. From 14 plantations in different sites, the natural infection occurrence in these populations ranged from 0 to 65%, while a lab colony exhibited an infection incidence of 70%. Spore density in haemolymph of symptomatic insects averaged 2.1 (± 0.4) × 107 spores/beetle. Symptoms in infected adults were identified by an abnormal abdomen with malformation of the second pair of wings, impairing their flight activity. Electron transmission microscopy of the pathogen showed morphological features similar to species belonging to the genus Nosema or Vairimorpha. Phylogenetic analysis of the full-length small subunit ribosomal RNA gene suggests this pathogen’s placement in the genus Vairimorpha, but with a sequence identity of ~ 94% with the nearest neighbours. The low level of sequence identity suggests this pathogen may represent a novel taxon in the genus and further requires whole genome sequencing for definitive taxonomic resolution. These findings provide insights on the natural occurrence of this novel pathogen of this invasive pest in Eucalyptus plantations in Brazil. Further studies are needed to determine potential of this microsporidium in the design of conservative or augmentative biological control programs for this invasive pest. School of Agricultural Sciences São Paulo State University (UNESP), Campus of Botucatu, Av. Universitária, 3780, Altos do Paraíso, Fazenda Experimental Lageado Laboratory of Environmental Microbiology Brazilian Agricultural Research Corporation Embrapa Environment, Rodovia SP-340, km 127.5 Botucatu Medical School Dept. Internal Medicine Sao Paulo State University (UNESP), Campus of Botucatu, Av. Prof. Mário Rubens Guimarães Montenegro, s/n USDA Agricultural Research Service National Center for Agricultural Utilization Research Crop Bioprotection Research Unit, 1815, N. University St School of Agricultural Sciences São Paulo State University (UNESP), Campus of Botucatu, Av. Universitária, 3780, Altos do Paraíso, Fazenda Experimental Lageado Botucatu Medical School Dept. Internal Medicine Sao Paulo State University (UNESP), Campus of Botucatu, Av. Prof. Mário Rubens Guimarães Montenegro, s/n

Mulberry silkworm, Bombyx mori L. is afflicted especially by microorganisms causing silkworm diseases. These diseases are caused by viruses (BmNPV, BmIFV, BmDNVs, BmCPV); bacteria (Bacillus thuringiensis, Staphylococcus spp., Streptococcus spp.); fungi (Beauveria bassiana, Nomuraea rileyi, Aspergillus flavus); microsporidians (Nosema bombycis, Vairimorpha spp., Pleistophora spp., Thelohania spp. and Microsporidium spp.). Silkworm diseases cause severe crop losses to the farmers as there are no curative measures for their management; only general prophylactic measures are readily available for preventing the incidence and spread of the diseases. Most of the external symptoms of silkworm diseases are atypical and except for a few, they could not be identified by tell-tale features. Disease diagnosis/detection plays a pivotal role in designing prevention strategies to offset the cocoon crop losses. Traditional light microscopy and histochemical methods are not practical; besides being not-so-sensitive; especially non-occluded viruses which possibly could not be detected; and non-specific. More sensitive and specific assays employed to detect/diagnose silkworm viral and microsporidian diseases are based on antigen-antibody (serological) reactions. The immunoassays developed for these purposes include precipitin, fluorescent antibody, immunoblotting, latex agglutination tests; enzyme-linked immunosorbent (ELISA) and dipstick immunoassays. These tests detect silkworm viruses and microsporidians at very low concentrations with high specificity in silkworm tissue and faecal matter. Silkworm larval rearings at a young age are often certified as disease free for further rearing and cocoon production utilizing several variants of latex agglutination, ELISA and dipstick immunoassays. This chapter presents methods for isolation, propagation, purification of silkworm pathogens and protocols for different immunodiagnostic methods.

Scientific and Technological Research Council of Turkey(Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)) The Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae) is one of the most important stored product pests. Fumigation plays a significant role in the management of insect pests in stored-products. However, the use of fumigants is problematic because of their effects on the environment and high costs. Entomopathogenic organisms are environmentally friendly control agents and suppress pest populations under natural conditions. In this study, distribution and occurrence of a microsporidian pathogen, Vairimorpha plodiae (Opisthokonta: Microspora) in the populations of P. interpunctella from 12 localities representing Turkey between 2019 and 2020 are presented for the first time by confirming its effectiveness on natural populations. The presence of the microsporidian pathogen was found in 11 of 12 (91.7%) populations. In total, 863 of 3,044 samples were infected by the pathogen. Infection mean was 28.4% for all populations. Our results showed that V. plodiae infection reached to a considerably high prevalence (88.77%) in P. interpunctella populations and varied from 5.1 to 88.7% between the populations. In addition, microsporidia infections have been identified throughout Turkey. We found that V. plodiae can infect all life stages of P. interpunctella. Totally, 623 (28.5%) of 2187 larvae, 14 (37.8%) of 37 pupae, 226 (27%) of 820 adults were found to be infected by the pathogen. There were considerable differences between the dead and living larvae. The microsporidian infection was found in 26 (11.6%) of 225 living larvae, whereas it was found in 595 (30.5%) of 1,952 dead larvae. These results confirm that the microsporidia pathogen has a high spreading potential in P. interpunctella populations and can be a natural biological suppression factor on pest populations. Scientific and Technological Research Council of Turkey [118O980]

A microsporidian pathogen was originally identified using molecular techniques from Oulema melanopus L. (Coleoptera, Chrysomelidae) under a "working name" Nosema oulemae, but its description was never published. In the present study, a microsporidian infection was detected in the Blue Shieldbug, Zicrona caerulea for the first time, showing 99.9% SSU rRNA sequence similarity to N. oulemae (Genbank accession U27359). Life cycle, tissue tropism, ultrastructure and phylogenetical relationships with other microsporidia species were disclosed. Nymph and adult stages of the host were infected with mature spores produced in the gut, hemocoel and fat body. Spores of the parasite measured approximately 4.50 ± 0.36 μm in length and 2.46 ± 0.18 μm in width on fresh smears. The number of coils of the polar filament was 9-11. Coils were 109.23 ± 22.92 nm (range: 93.75-268.66; n = 50) in diameter and consisted of seven concentric layers of different electron density and thickness. The spores possessed a relatively thick (174.04 ± 57.65 nm) trilaminar spore wall. Developmental sequence and ultrastructure The SSU rRNA and RPB1 gene sequences were deposited GenBank under accession MT102274 and MW538912. Basing upon the sequence similarity, the isolate from Z. caerulea can be attributed to the species from O. melanopus provisionally designated as N. oulemae. The novel species Vairimorpha hostounsky sp. nov. is described, named after Prof. Zdenek Hostounsky who was the first to discover this parasite.

Background: Vairimorpha (Nosema) ceranae is the most common eukaryotic gut pathogen in honey bees, Apis mellifera. Infection is typically chronic but may result in mortality. Additional factors may be involved in mortality, including the honey bee gut microbiota. Previous studies of V. ceranae and gut microbiota identified positive associations between core bacteria and V. ceranae infection. These possibly synergistic or mutualistic associations are often disregarded because some core bacteria act as probiotic symbionts. Methods: To clarify the effects caused by the positive associations, we added isomaltooligosaccharide (IMO), a prebiotic also found in honey, to alter the interactions between V. ceranae and gut bacteria. Mortality and sugar consumption of the caged bees were monitored. Infection intensities and gut bacteria were examed after 12 days post inoculation, the plateau phase of infection. The gut bacteria were evaluated using both qPCR and 16S rDNA sequencing.Results: We confirmed that V. ceranae infections alone significantly enhance several core bacterial populations, including Bifidobacterium spp., Snodgrassella alvi, and Gilliamella apicola in the honey bee hindgut microbiota. Moreover, the qPCR results suggested that V. ceranae infected bees had significantly higher bacterial microbiota populations. In addition to the enhanced core bacteria, Commensalibacter and Bartonella were significantly increased in the fecal microbiome. Infected bees fed IMO had significantly higher V. ceranae spore counts but lower mortality; however, infected bees fed IMO did not have significant changes in gut bacteria populations compared to those fed only sucrose, but feeding IMO further reduced the fecal microbiome alpha-diversity. Conclusions: The microbiota alterations caused by infection were similar to the microbiota differences found between summer bees and winter bees, the latter of which have longer lifespans, and feeding IMO increased this similarity. Our results indicated that the interactions between gut bacteria and V. ceranae not only enhanced both the pathogen and bacteria populations but also sustained the host survival. This mutualistic interaction potentially enhances disease transmission and avoids social immune responses of the honey bee hosts.

The beet webworm Loxostege sticticalis (LS) has eruptive type of population dynamics and high migratory activity. The LS outbreaks are therefore difficult to predict and the pest belongs to the category of highly dangerous pests. However, during periods of depressions this insect is not observed within the most of its range and is very susceptible to infection by pathogens, including various species of microsporidia, some of which are not specific parasites of the order Lepidoptera. The distribution of LS microsporidia in Eurasia is quite extensive. During the study period of LS from 2003 to 2019, we have found 6 species of microsporidia. The parasite list includes not only species known for Lepidoptera such as Nosema sp. and Vairimorpha thomsoni, but also Vairimorpha (Nosema) ceranae as the typical pathogen from Apis mellifera, as well as Endoreticulatus cf poecilimonae, a pathogen similar to Endoreticulatus poecilimonae from Poecilimon thoracicus. Moreover, two isolates from the genus Tubulinosema identified in LS belong to the group of parasites with a very wide host range, including humans. In laboratory experiments, LS proved high sensitivity to microsporidia N. pyrausta from Ostrinia nubilalis and N. tyriae from Tyria jacobaeae. Its susceptibility to Paranosema locustae from Locusta migratoria has also been discovered.

Microsporidia Vairimorpha (Nosema) ceranae is an emergent parasite of honeybee Apis mellifera and has a great concern to apiculture due to high pathogenesity and fumagillin resistance. Recently RNA interference and single-chain antibodies technologies are proposed to create unsusceptible to intracellular parasites breeds of insects. In this study we established cell culture model system to provide a way to investigate the molecular basis of interactions between honeybee and its pathogen. As the first step in this direction V. ceranae spores were isolated from living bees, properly sterilized and in vitro germinated with Sf9 lepidopteran-derived cell line. The entire life circle of this parasite was achieved. This should allow us to develop the novel treatment strategy directed to inhibit propagation of V. ceranae intracellular stages with recombinant antibodies targeted to the vitally important membrane transporters.

Research pertaining to the two closely-related microsporidian genera Nosema and Vairimorpha is hindered by inconsistencies in species differentiation within and between the two clades. One proposal to better delimit these genera is to restructure the Nosema around a "True Nosema" clade, consisting of species that share a characteristic reversed ribosomal DNA operon arrangement and small subunit (SSU) ribosomal DNA sequences similar to that of the Nosema type species, N. bombycis. Using this framework, we assess two distinct microsporidia recovered from the forest insect Bruce spanworm (Operophtera bruceata) by sequencing their SSU and internal transcribed spacer regions. Phylogenetic analyses place one of our isolates within the proposed True Nosema clade close to N. furnacalis and place the other in the broader Nosema/Vairimorpha clade close to N. thomsoni. We found that 25% of Bruce spanworm cadavers collected over the four-year study period were infected with microsporidia, but no infections were detected in cadavers of the Bruce spanworm's invasive congener, the winter moth (O. brumata), collected over the same period. We comment on these findings as they relate to the population dynamics of the Bruce spanworm-winter moth system in this region, and more broadly, on the value of ribosomal DNA operon arrangement in Nosema systematics.

The microsporidiosis of the endangered white-clawed crayfish Austropotamobius pallipes complex has generally been attributed to only one species, Thelohania contejeani, the agent of porcelain disease. Species identification was mostly assessed by macroscopic examination or microscopic evaluation of muscle samples rather than by molecular or ultrastructural analyses. A survey conducted on A. pallipes complex populations in Northern Italy highlighted the presence of two different microsporidia causing similar muscular lesions, T. contejeani and an undescribed octosporoblastic species Vairimorpha austropotamobii sp. nov. Mature spores and earlier developmental stages of V. austropotamobii sp. nov. were found within striated muscle cells of the thorax, abdomen, and appendages of the crayfish. Only octosporoblastic sporogony within sporophorous vesicles (SPVs) was observed. Diplokaryotic sporonts separated into two uninucleate daughter cells, which gave rise to a rosette-shaped plasmodium, and eight uninucleate spores were produced within the persistent SPV. Ultrastructural features of stages in the octosporoblastic sequence were similar to those described for Vairimorpha necatrix, the type species. Mature spores were pyriform in shape and an average of 3.9 × 2.2 µm in size. The polar filament was coiled 11-14 times, lateral to the posterior vacuole. The small subunit ribosomal RNA gene (SSU rRNA) and the large subunit RNA polymerase II gene (RPB1) of V. austropotamobii sp. nov. were sequenced and compared with other microsporidia. The highest sequence identity of SSU rRNA (99%) and RPB1 (74%) genes was with the amphipod parasite Nosema granulosis and subsequently with V. cheracis, which infects the Australian yabby Cherax destructor. In our work we discuss about the reasons for placing this new species in the genus Vairimorpha. In addition, we provide for T. contejeani a RPB1 gene sequence, supplemental sequences of SSU rRNA gene and ultrastructural details of its sporogony in the host A. pallipes complex.

Vairimorpha (Nosema) ceranae is the most common eukaryotic gut pathogen in honey bees. Infection is typically chronic but may result in mortality. Gut microbiota is a factor that was recently noted for gut infectious disease development. Interestingly, studies identified positive, instead of negative, associations between core bacteria of honey bee microbiota and V. ceranae infection. To investigate the effects of the positive associations, we added isomaltooligosaccharide (IMO), a prebiotic sugar also found in honey, to enhance the positive associations, and we then investigated the infection and the gut microbiota alterations using qPCR and 16S rRNA gene sequencing. We found that infected bees fed IMO had significantly higher V. ceranae spore counts but lower mortalities. In microbiota comparisons, V. ceranae infections alone significantly enhanced the overall microbiota population in the honey bee hindgut and feces, all monitored core bacteria significantly increased in the quantities but not all in the population ratios. The microbiota alterations caused by the infection were enhanced with IMO, and these alterations were similar to the differences found in bees that naturally have longer lifespans. Although our results did not clarify the causations of the positive associations between the infections and microbiota, the associations seemed to sustain the host survival and benefit the pathogen. Enhancing indigenous gut microbe to control nosema disease may result in an increment of bee populations but not the control of the pathogen. This interaction between the pathogen and microbiota potentially enhances disease transmission and avoids the social immune responses that diseased bees die prematurely to curb the disease from spreading within colonies.

The microsporidian genera Nosema and Vairimorpha comprise a clade described from insects. Currently the genus Nosema is defined as having a dimorphic life cycle characterized by diplokaryotic stages and diplosporoblastic sporogony with two functionally and morphologically distinct spore types ("early" or "primary" and "environmental"). The Vairimorpha life cycle, in addition to a Nosema-type diplokaryotic sporogony, includes an octosporoblastic sporogony producing eight uninucleate spores (octospores) within a sporophorous vesicle. Molecular phylogeny, however, has clearly demonstrated that the genera Nosema and Vairimorpha, characterized by the absence or presence of uninucleate octospores, respectively, represent two polyphyletic taxa, and that octosporogony is turned on and off frequently within taxa, depending on environmental factors such as host species and rearing temperature. In addition, recent studies have shown that both branches of the Vairimorpha-Nosema clade contain species that are uninucleate throughout their life cycle. The SSU rRNA gene sequence data reveal two distinct clades, those closely related to Vairimorpha necatrix, the type species for the genus Vairimorpha, and those closely related to Nosema bombycis, the type species for the genus Nosema. Here, we redefine the two genera, giving priority to molecular character states over those observed at the developmental, structural or ultrastructural levels and present a list of revised species designations. Using this approach, a series of species are renamed (combination novum) and members of two genera, Rugispora and Oligosporidium, are reassigned to Vairimorpha because of their phylogenetic position. Moreover, the family Nosematidae is redefined and includes the genera Nosema and Vairimorpha comprising a monophyletic lineage of Microsporidia.

Sample collections of Solenopsis invicta Buren (Hymenoptera: Formicidae) were taken from 20 islands of the West Indies and evaluated for the presence of key pathogens and parasites of this invasive pest ant. We hypothesized that bottleneck events during the introduction of this ant species in the West Indies would have resulted in populations devoid, or nearly so, of natural enemies. Monogyne and polygyne social forms were found throughout the islands surveyed with monogyny being more prevalent (65%) compared with polygyny (35%). Among 254 samples, only 25 (~10%) tested positive for the presence of pathogens or parasites. The microsporidian Kneallhazia solenopsae was the most prevalent pathogen detected; it was found in 20 colonies. A second microsporidian species, Vairimorpha invictae, was shown to be present in a polygyne sample collected from St. Croix—the first detection of this pathogen outside South America. Similarly, Solenopsis invicta densovirus (SiDNV) was detected in one polygyne sampl...

An isolate of the microsporidium Vairimorpha ephestiae (originally isolated from Ephestia kuhniella) from collection of Prof. J. Weiser was propagated in a laboratory culture of Galleria mellonella. Only disporoblastic sporogony was observed and formation of octospores, characteristic of the genus Vairimorpha, never occurred. A partial nucleotide sequence of the small subunit rRNA gene (1247 bp) for this microsporidium showed 100% identity to the homologous sequences of Vairimorpha (Nosema) necatrix (Genbank accession # U11051 and # DQ996241), a microsporidium with a broad host range within the Lepidoptera. Sequence similarity of protein-coding genes (RPB1, HSP70 and actin) between V. ephestiae and V. necatrix was about 98–100%. The level of genetic polymorphism in the RPB1 locus between these two species was essentially the same as between isolates of V. necatrix. It is therefore concluded that V. ephestiae is in fact an isolate of V. necatrix and the former species should be synonymized with the latter. Though described later, V. necatrix has prevailing usage and its precedence over V. ephestiae is proposed to conserve stability and avoid confusion.

BAKI, Hilal/0000-0002-6072-5543; BEKIRCAN, CAGRI/0000-0002-5968-7359 WOS: 000424857300022 PubMed: 29258841 A new microsporidium was isolated from Subcoccinella vigintiquatuorpunctata L. (Coleoptera: Coccinellidae), a pest of Galega officinalis L. in Turkey. Infection in larval and adult stages was systemic with mature spores produced in the midgut, gonads, Malpighian tubules and, most extensively, fat body tissues. The microsporidium was polymorphic with two sporulation sequences producing two types of spores, binucleate spores with 13-15 coils of the polar tube, and uninucleate spores with 7 coils of the polar tube that developed within a sporophorous vesicle (SPV) to form meiospores. The 16S small subunit rRNA (SSU rRNA) gene of the microsporidium was sequenced and compared with twenty-seven microsporidian sequences from GenBank. Based on the phylogenetic analysis of the SSU rRNA sequence, this microsporidium is unique within the Vairimorpha group. Morphological and genetic characters indicate that the described microsporidium is dissimilar to all known Vairimorpha species, and so is named here as Vairimorpha subcoccinellae n. sp. Scientific Research Committee of Giresun University [FEN-BAP-A-220413-48] The study was supported by the Scientific Research Committee of Giresun University (FEN-BAP-A-220413-48). We are thankful to Mehmet Ali Ozdes for making this study possible. We are grateful to James J. Becnel Ph.D. for reading the manuscript and for his valuable comments.

Microsporidia are intracellular parasites of insects and other higher eukaryotes. The microsporidian Nosema philosamiae Talukdar, 1961 was isolated from the eri silkworm, Philosamia cynthia ricini Grote. In the present study, alpha- and beta-tubulin genes from N. philosamiae were characterized. The identity analysis of nucleotide and amino acid sequences indicated high similarity with species of Nosema Nageli, 1857 sensu lato (nucleotide sequences, > or = 96.0%; amino acid sequences, > or = 99.0%). However, the tubulin genes of N. philosamiae share low sequence similarity with that of N. ceranae Fries, Feng, da Silva, Slemenda et Pieniazek, 1996 (strain BRL01) and a Nosema/Vairimorpha species. Phylogenies based on alpha-, beta- and combined alpha- plus beta-tubulin gene sequences showed that N. philosamiae, along with the true Nosema species, forms a separate clade with a high bootstrap value, with N. ceranae BRL01 forming a clade of its own. The results indicated that the alpha- and beta-tubulin sequences may be useful as a diagnostic tool to discriminate the true Nosema group from the Nosema/Vairimorpha group.

We designed fluorescence in situ hybridization probes for two distinct microsporidian clades and demonstrated their application in detecting, respectively, Nosema / Vairimorpha and Dictyoceola species. We used them to study the vertical transmission of two microsporidia infecting the amphipod Gammarus duebeni .

The microsporidian parasite designated here as Nosema sp. Isolate YNPr was isolated from the cabbage butterfly Pieris rapae collected in Honghe Prefecture, Yunnan Province, China. The genome was sequenced by Illumina sequencing and compared to those of two related members of the Nosema/Vairimorpha clade, Nosema ceranae and Nosema apis. Based upon assembly statistics, the Nosema sp. YNPr genome is 3.36 x 106bp with a G+C content of 23.18% and 2,075 protein coding sequences. An “ACCCTT” motif is present approximately 50-bp upstream of the start codon, as reported from other members of the clade and from Encephalitozoon cuniculi, a sister taxon. Comparative small subunit ribosomal DNA (SSU rDNA) analysis as well as genome-wide phylogenetic analysis confirms a closer relationship between N. ceranae and Nosema sp. YNPr than between the two honeybee parasites N. ceranae and N. apis. The more closely related N. ceranae and Nosema sp. YNPr show similarities in a number of structural characteristics such as gene synteny, gene length, gene number, transposon composition and gene reduction. Based on transposable element content of the assemblies, the transposon content of Nosema sp. YNPr is 4.8%, that of N. ceranae is 3.7%, and that of N. apis is 2.5%, with large differences in the types of transposons present among these 3 species. Gene function annotation indicates that the number of genes participating in most metabolic activities is similar in all three species. However, the number of genes in the transcription, general function, and cysteine protease categories is greater in N. apis than in the other two species. Our studies further characterize the evolution of the Nosema/Vairimorpha clade of microsporidia. These organisms maintain variable but very reduced genomes. We are interested in understanding the effects of genetic drift versus natural selection on genome size in the microsporidia and in developing a testable hypothesis for further studies on the genomic ecology of this group.