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PLoS Pathogens Feb 2020
Topics: Animals; Evolution, Molecular; Microsporidia; Phylogeny
PubMed: 32053705
DOI: 10.1371/journal.ppat.1008276 -
Current Biology : CB Nov 2008Microsporidia are obligate, intracellular eukaryotic pathogens that infect animal cells, including humans [1]. Previous studies suggested microsporidia share a common...
Microsporidia are obligate, intracellular eukaryotic pathogens that infect animal cells, including humans [1]. Previous studies suggested microsporidia share a common ancestor with fungi [2-7]. However, the exact nature of this phylogenetic relationship is unclear because of unusual features of microsporidial genomes, which are compact with fewer and highly divergent genes [8]. As a consequence, it is unclear whether microsporidia evolved from a specific fungal lineage, or whether microsporidia are a sister group to all fungi. Here, we present evidence addressing this controversial question that is independent of sequence-based phylogenetic reconstruction, but rather based on genome structure. In the zygomycete basal fungal lineage, the sex locus is a syntenic gene cluster governing sexual reproduction in which a high mobility group (HMG) transcription-factor gene is flanked by triose-phosphate transporter (TPT) and RNA helicase genes [9]. Strikingly, microsporidian genomes harbor a sex-related locus with the same genes in the same order. Genome-wide synteny analysis reveals multiple other loci conserved between microsporidia and zygomycetes to the exclusion of all other fungal lineages with sequenced genomes. These findings support the hypothesis that microsporidia are true fungi that descended from a zygomycete ancestor and suggest microsporidia may have an extant sexual cycle.
Topics: Biological Evolution; Genes, Mating Type, Fungal; Genome, Fungal; Microsporidia; Molecular Sequence Data; Synteny
PubMed: 18976912
DOI: 10.1016/j.cub.2008.09.030 -
Microbes and Infection Apr 2001A survey of the molecular features of microsporidia is presented which attempts to comment on unresolved questions concerning the physiology of these amitochondrial... (Review)
Review
A survey of the molecular features of microsporidia is presented which attempts to comment on unresolved questions concerning the physiology of these amitochondrial intracellular parasites. Various transports of host-derived molecules can be predicted and trehalose appears as a potential reserve of glucose for energy metabolism. Significant insights into membrane lipids, polyamine metabolism and sporogony-specific proteins have been gained. Some species, such as Encephalitozoon cuniculi, are heterogeneous entities and harbor a small genome. Although showing a variation in genome size of 8.5-fold, microsporidia share reduced rDNA genes. Finally, data on gene organization and a possible evolutionary relationship with fungi are considered.
Topics: Animals; DNA, Protozoan; DNA, Ribosomal; Enterocytozoon; Evolution, Molecular; Genetic Variation; Genome, Protozoan; Host-Parasite Interactions; Microsporidia; Phylogeny
PubMed: 11369278
DOI: 10.1016/s1286-4579(01)01398-3 -
Revista Chilena de Infectologia :... 2018
Topics: Microsporidia; Microsporidiosis
PubMed: 29652974
DOI: 10.4067/s0716-10182018000100073 -
Folia Parasitologica 1993Comparative data are given of microsporidian infections in insects and mammals. Due to minute size and diffuse distribution in mammals microsporidia were recognized in... (Comparative Study)
Comparative Study Review
Comparative data are given of microsporidian infections in insects and mammals. Due to minute size and diffuse distribution in mammals microsporidia were recognized in vertebrates only during search for virus infections. Early infections with Encephalitozoon in rearings of laboratory animals contaminated many isolates of other protozoan infections. Old separate descriptions of microsporidia in mice, rabbits or dogs have to be reevaluated with modern methods of molecular analysis. Old cases of infection of man known now as Encephalitozoon chagasi or Encephalitozoon sp. Matsubayashi are not belonging to the genus Encephalitozoon and should be jointly studied with Nosema connori as eventually identical. With actual improvements of methods of diagnostics the net of detection of microsporidia in man should be extended on routine testing of urine, faecal samples, eye and nose biopsies and other materials including vaginal smears. The way of circulation of the infections in the host organisms must be studied.
Topics: Animals; Encephalitozoon; Humans; Insecta; Mice; Microsporida; Microsporidiosis; Muridae; Nosema; Rodent Diseases; Tissue Distribution
PubMed: 8013925
DOI: No ID Found -
In Vitro Cellular & Developmental... 2009The use of animal cell cultures as tools for studying the microsporidia of insects and mammals is briefly reviewed, along with an in depth review of the literature on... (Review)
Review
The use of animal cell cultures as tools for studying the microsporidia of insects and mammals is briefly reviewed, along with an in depth review of the literature on using fish cell cultures to study the microsporidia of fish. Fish cell cultures have been used less often but have had some success. Very short-term primary cultures have been used to show how microsporidia spores can modulate the activities of phagocytes. The most successful microsporidia/fish cell culture system has been relatively long-term primary cultures of salmonid leukocytes for culturing Nucleospora salmonis. Surprisingly, this system can also support the development of Enterocytozoon bienusi, which is of mammalian origin. Some modest success has been achieved in growing Pseudoloma neurophilia on several different fish cell lines. The eel cell line, EP-1, appears to be the only published example of any fish cell line being permanently infected with microsporidia, in this case Heterosporis anguillarum. These cell culture approaches promise to be valuable in understanding and treating microsporidia infections in fish, which are increasingly of economic importance.
Topics: Animals; Cells, Cultured; Fishes; Insecta; Microsporidia; Research
PubMed: 19184249
DOI: 10.1007/s11626-008-9172-3 -
Contributions To Microbiology 2000Knowledge about the phylum Microspora and its relationship to humans is in a period of rapid growth as noninvasive diagnostic techniques for microsporidia have been... (Review)
Review
Knowledge about the phylum Microspora and its relationship to humans is in a period of rapid growth as noninvasive diagnostic techniques for microsporidia have been developed and are being applied to both clinical and epidemiologic studies. As these techniques have improved, new microsporidian pathogens and reservoir hosts of the microsporidia infecting humans are being identified. Recent phylogenetic data suggest that microsporidia are related to the fungi. This information may prove useful in investigations into new therapeutic strategies for these emerging human pathogens.
Topics: Animals; Humans; Microsporidia; Microsporidiosis; Phylogeny; Polymerase Chain Reaction
PubMed: 10943514
DOI: 10.1159/000060362 -
Parasitology Research May 2014Molecular phylogenies based on the small subunit ribosomal RNA gene (SSU or 18S ribosomal DNA (rDNA)) revealed recently the existence of a relatively large and...
Molecular phylogenies based on the small subunit ribosomal RNA gene (SSU or 18S ribosomal DNA (rDNA)) revealed recently the existence of a relatively large and widespread group of eukaryotes, branching at the base of the fungal tree. This group, comprising almost exclusively environmental clones, includes the endoparasitic chytrid Rozella as the unique known representative. Rozella emerged as the first fungal lineage in molecular phylogenies and as the sister group of the Microsporidia. Here we report rDNA molecular phylogenetic analyses of two endonuclear parasites of free-living naked amoebae having microsporidia-like ultrastructural features but belonging to the rozellids. Similar to microsporidia, these endoparasites form unflagellated walled spores and grow inside the host cells as unwalled nonphagotrophic meronts. Our endonuclear parasites are microsporidia-like rozellids, for which we propose the name Paramicrosporidium, appearing to be the until now lacking morphological missing link between Fungi and Microsporidia. These features contrast with the recent description of the rozellids as an intermediate wall-less lineage of organisms between protists and true Fungi. We thus reconsider the rozellid clade as the most basal fungal lineage, naming it Rozellomycota.
Topics: Amoeba; DNA, Fungal; DNA, Ribosomal Spacer; Microscopy, Electron, Transmission; Microsporidia; Phylogeny
PubMed: 24652444
DOI: 10.1007/s00436-014-3838-4 -
Parasite (Paris, France) 2022Cases of intestinal microsporidiosis infection are underestimated and affect both immunocompromized and immunocompetent patients. Real-time PCR is superseding...
Cases of intestinal microsporidiosis infection are underestimated and affect both immunocompromized and immunocompetent patients. Real-time PCR is superseding microscopic examination for its diagnosis in medical analysis laboratories. However, few manufacturers include microsporidia in their PCR panel for the diagnosis of infectious gastroenteritis. Here, we evaluated the performances of the real-time PCR assays microsporidia generic and microsporidia typing (Bio-Evolution, France) on the Rotor-Gene Q real-time PCR cycler (Qiagen, France). We included 45 negative and 44 positive stool samples for Enterocytozoon bieneusi (n = 34, with various genotypes), Encephalitozoon intestinalis (n = 4), Encephalitozoon hellem (n = 4), and Encephalitozoon cuniculi (n = 2). We also studied a four-year survey of an inter-laboratory quality control program including 9 centers that used this commercial assay. Sensitivity and specificity of the microsporidia generic assay were 86.4% and 93.3%, respectively. Encephalitozoon hellem and Encephalitozoon cuniculi were detected by the microsporidia generic PCR assay but not by the microsporidia typing PCR assay. These results were consistent with the results of the inter-laboratory quality control program. In conclusion, Bio-Evolution Real-time PCR assays are useful tools for intestinal microsporidiosis, but negative results for microsporidia typing assays require supplementary analyses to confirm E. hellem or E. cuniculi infections.
Topics: Humans; Microsporidia; Real-Time Polymerase Chain Reaction; Microsporidiosis; Enterocytozoon
PubMed: 36426934
DOI: 10.1051/parasite/2022055 -
Clinical Microbiology Reviews Apr 1999Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. These parasites are now recognized as one of the... (Review)
Review
Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. These parasites are now recognized as one of the most common pathogens in human immunodeficiency virus-infected patients. For most patients with infectious diseases, microbiological isolation and identification techniques offer the most rapid and specific determination of the etiologic agent. This is not a suitable procedure for microsporidia, which are obligate intracellular parasites requiring cell culture systems for growth. Therefore, the diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Although the diagnosis of microsporidiosis and identification of microsporidia by light microscopy have greatly improved during the last few years, species differentiation by these techniques is usually impossible and transmission electron microscopy may be necessary. Immunfluorescent-staining techniques have been developed for species differentiation of microsporidia, but the antibodies used in these procedures are available only at research laboratories at present. During the last 10 years, the detection of infectious disease agents has begun to include the use of nucleic acid-based technologies. Diagnosis of infection caused by parasitic organisms is the last field of clinical microbiology to incorporate these techniques and molecular techniques (e.g., PCR and hybridization assays) have recently been developed for the detection, species differentiation, and phylogenetic analysis of microsporidia. In this paper we review human microsporidial infections and describe and discuss these newly developed molecular techniques.
Topics: Animals; DNA, Protozoan; Humans; Microsporidia; Microsporidiosis; Nucleic Acid Hybridization; Phylogeny; Polymerase Chain Reaction
PubMed: 10194459
DOI: 10.1128/CMR.12.2.243