Ultrastructural and molecular characterization of Glugea serranus n. sp., a microsporidian infecting the blacktail comber, Serranus atricauda (Teleostei: Serranidae), in the Madeira Archipelago (Portugal).
A new microsporidian infecting the connective tissue of the coelomic cavity of the blacktail comber Serranus atricauda, in the Madeira Archipelago (Portugal), is described on the basis of morphological, ultrastructural, and molecular features. The microsporidian formed large whitish xenomas adhering to the peritoneal visceral organs of the host. Each xenoma consisted of a single hypertrophic cell, in the cytoplasm of which mature spores proliferated within parasitophorous vacuoles surrounded by numerous collagen fibers. Mature spores were ellipsoidal and uninucleated, measuring an average of 6.5 ± 0.5 μm in length and 3.4 ± 0.6 μm in width. The anchoring disk of the polar filament was subterminal, laterally shifted from the anterior pole of the spore. The isofilar polar filament coiled in 18-19 turns, forming two rows that surrounded the posterior vacuole. The latter occupied about one third of the spore length. The polaroplast surrounding the apical and uncoiled portion of the polar filament displayed two distinct regions: a lamellar region and an electron-dense globule. Molecular analysis of the rRNA genes, including the internal transcribed spacer region, and phylogenetic analysis using maximum likelihood and neighbor joining demonstrated that this microsporidian parasite clustered with some Glugea species. Based on the differences found both at the morphological and molecular levels, to other members of the genus Glugea, the microsporidian infecting the blacktail comber is considered a new species, thus named Glugea serranus n. sp.
Department of Sciences, University Institute of Health Sciences, CESPU, 4585-116, Gandra, Portugal.|Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4050-123, Porto, Portugal.|Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS/UP), University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal.
Graça
G
Casal
Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4050-123, Porto, Portugal.|Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS/UP), University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal.
Sónia
S
Rocha
Marine Biological Station of Funchal, University of Madeira, 9000-107, Funchal, Madeira, Portugal.
Graça
G
Costa
Zoology Department, College of Sciences, King Saud University, Riyadh, 11451, Saudi Arabia.
Saleh
S
Al-Quraishy
Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4050-123, Porto, Portugal. azevedoc@icbas.up.pt.|Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS/UP), University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal. azevedoc@icbas.up.pt.|Zoology Department, College of Sciences, King Saud University, Riyadh, 11451, Saudi Arabia. azevedoc@icbas.up.pt.
Carlos
C
Azevedo
D000818:Animals; D001492:Bass; D005393:Fish Diseases / Q000382:microbiology*; D050220:Glugea / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D016881:Microsporidiosis / Q000382:microbiology / Q000662:veterinary*; D010802:Phylogeny; D011174:Portugal; D017422:Sequence Analysis, DNA / Q000662:veterinary
Fine structure; Fish parasite; Microsporidia; rRNA genes