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1.
Eur J Protistol ; 72: 125659, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31825791

RESUMO

Three species of tintinnines, namely Tintinnopsis tentaculata Nie and Cheng, 1947, Tintinnopsis orientalis Kofoid and Campbell, 1929, and Eutintinnus lususundae (Entz, 1885) Kofoid and Campbell, 1939, were isolated from coastal waters of China. The morphology of each was investigated based on observations of live and protargol-stained specimens, and their SSU rDNA- and LSU rDNA-based phylogenetic relationships were analyzed. The ciliary patterns of these species are revealed for the first time. Based on the original descriptions and data from the present study, an improved diagnosis is given for each species. Unlike its congeners, the second dorsal kinety of Eutintinnus lususundae is displaced below the left ciliary field, which may suggest that the second dorsal kinety is evolving into a posterior kinety by a migration process. The ventral kinety in Eutintinnus is redefined. A neotype is fixed for T. tentaculata to stabilize the species name objectively, mainly because of the unavailability of type material.


Assuntos
Cilióforos/classificação , Água do Mar/parasitologia , China , Cilióforos/citologia , Cilióforos/genética , DNA de Protozoário/genética , Filogenia , RNA Ribossômico 18S/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Especificidade da Espécie
2.
Eur J Protistol ; 72: 125643, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31734636

RESUMO

The colonization features of periphytic protozoa have proved to be a useful tool for indicating water quality status in aquatic ecosystems. In order to reveal the seasonal variations in colonization dynamics of the protozoa, a 1-year baseline survey was carried out in coastal waters of the Yellow Sea, northern China. Using glass slides as artificial substrates, a total of 240 slides were collected at a depth of 1 m in four seasons after colonization periods of 3, 7, 10, 14, 21, and 28 days. A total of 122 ciliate species were identified with 21 dominant species. The colonization dynamics of the protozoa were well fitted to the MacArthur-Wilson and logistic models in all four seasons (P < 0.05). However, the equilibrium species numbers (Seq), colonization rates (G), and the time to 90% Seq (T90%) represented a clear seasonal variability: (1) more or less similar levels in spring and autumn (Seq = 29/23; G = 0.301/0.296; T90%=7.650/7.779); (2) with a significant difference in summer and winter (Seq = 32/121; G = 0.708/0.005; T90% = 3.252/479.705). Multivariate approaches demonstrated that the exposure time for the species composition and community structure of the protozoa to an equilibrium period were 10-14 days in spring and autumn, but less and more time periods were needed in summer and winter, respectively. Based on the results, we suggest that the colonization dynamics of periphytic protozoa were different within four seasons, and an optimal sampling strategy for monitoring surveys should be modified during different seasons in marine ecosystems.


Assuntos
Biodiversidade , Cilióforos/fisiologia , Estações do Ano , Água do Mar/parasitologia , China , Monitoramento Ambiental , Modelos Logísticos
3.
Sci Total Environ ; 698: 134289, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514034

RESUMO

Microeukaryotes are the key ecosystem drivers mediating marine productivity, the food web and biogeochemical cycles. The northwestern Pacific Ocean (NWPO), as one of the world's largest oligotrophic regions, remains largely unexplored regarding diversity and biogeography of microeukaryotes. Here, we investigated the community composition and geographical distribution of microeukaryotes collected from the euphotic zone of three different regions in the NWPO using high-throughput sequencing of the 18S rRNA gene and quantified the contributions of environmental factors on the distributions of microeukaryotes. The relative abundance of different group taxa, except for Ciliophora, presented distinct patterns in each region, and Metazoa and Dinoflagellata dominated the community, contributing approximately half of reads abundance. Spatial and environmental factors explained 66.01% of community variation in the NWPO. Temperature was the most important environmental factor significantly correlated with community structure. Bacterial biomass was also significantly correlated with microeukaryotic distribution, especially for Dinoflagellata and Diatomea. Network analysis showed strong correlations between microeukaryotic groups and free-living bacteria and different bacterial taxa were correlated with specific microeukaryotic groups, indicating that their interactions enabled microeukaryotic groups to adapt to diverse environments. This study provides a first glance at the diversity and geographical distribution of microeukaryotes in the NWPO and sheds light on the biotic and abiotic factors in shaping the microeukaryotic community in the ocean.


Assuntos
Biodiversidade , Monitoramento Ambiental , Cilióforos , Diatomáceas , Dinoflagelados , Ecossistema , Eutrofização , Oceano Pacífico , Água do Mar
4.
Eur J Protistol ; 72: 125663, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31869711

RESUMO

In this study, we investigated the morphology and molecular phylogeny of four marine or brackish spirotrichean ciliates found in China, namely: Caryotricha sinica sp. nov., Prodiscocephalus orientalis sp. nov., P. cf. borrori, and Certesia quadrinucleata. Caryotricha sinica is characterized by its small size, seven cirral rows extending posteriorly to about 65% of the cell length, and four transverse cirri. Prodiscocephalus orientalis differs from its congeners mainly by the number of cirri in the "head" region and on the ventral side. The SSU rDNA sequence of P. cf. borrori differs from that of other population of P. borrori by ca. 40 bp. Consequently, the nominal species P. borrori is considered to be a species-complex. New data are provided for Certesia quadrinucleata. The Chinese population of C. quadrinucleata, for example, has fewer left marginal cirri than the other populations for which such data are available. Phylogenetic analyses based on SSU rDNA sequence data show that the genus Caryotricha is monophyletic. All typical "discocephalids" with a discoid "head" form a strongly supported clade that is sister to the unstable uronychiids + pseudoamphisiellids clade within the Euplotia. The genus Certesia forms a sister group to the Euplotes clade, also within the Euplotia assemblage.


Assuntos
Cilióforos/classificação , Cilióforos/citologia , Filogenia , Água do Mar/parasitologia , China , Cilióforos/genética , Águas Salinas , Especificidade da Espécie
5.
Zootaxa ; 4585(3): zootaxa.4585.3.4, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31716156

RESUMO

The aims of this study were to identify and quantify the gastrointestinal ciliates from Brazilian domestic horses, to compare the data obtained with previous studies and to review data on ciliate communities associated with horses around the world. We used eight domestic horses, kept under extensive management. Fecal samples were obtained immediately after defecation of animals and fixed in 18.5% formaldehyde. We identify 24 species of endosymbiotic ciliates, distributed in two subclasses, two orders, five families and 13 genera. The ciliate composition was similar among the animals analyzed. The family Blepharocorythidae presented the higher prevalence and the family Buetschliidae was observed in greater abundance and density. Among the species identified, Cycloposthium dentiferum was observed for the first time in Central and South America and Bundleia elongata, B. inflata, B. piriformis, B. vorax and Cycloposthium psicauda, were observed for the first time in the American continent. In addition, the species Buissonella tapiri, which was originally discovered in fecal contents of the American tapir (Tapirus terrestris) in Brazil was observed for the first time associated to Equus caballus. The review on the ciliate communities associated with horses around the world demonstrated that the equine ciliates are a very diversified group with representatives in two subclasses, Suctoria and Trichostomatia, totaling 78 species distributed in three orders and six families, having been registered in different equine hosts (Equus asinus, Equus caballus and Equus quagga) and geographic locations (USA, China, Russia, Taiwan, Mexico, Cyprus, Turkey, Kyrgyzstan and Brazil).


Assuntos
Alveolados , Cilióforos , Animais , Brasil , China , Chipre , Equidae , Cavalos , Quirguistão , México , Federação Russa , Taiwan , Turquia
6.
Zootaxa ; 4664(2): zootaxa.4664.2.3, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31716677

RESUMO

Four cyrtophorian ciliates, Chlamydodon pararoseus sp. n., Chlamydodon bourlandi Qu et al., 2018, Dysteria crassipes Claparède Lachmann, 1859, and Dysteria monostyla (Ehrenberg, 1838) Kahl, 1931, isolated from coastal waters off China, were investigated using morphological and SSU rDNA sequencing techniques. C. pararoseus sp. n. can be recognized by having a kidney-shaped body, a complete cross-striated band, 44-51 somatic kineties, and 11-14 nematodesmal rods. The other three species were re-described based on new populations. Additionally, the SSU rRNA genes of C. pararoseus sp. n. and D. monostyla were sequenced for the first time. Phylogenetic analyses inferred from SSU rRNA gene sequences reveal that C. pararoseus sp. n. has a close relationship with C. bourlandi and C. mnemosyne Gong et al., 2005 within the genus Chlamydodon; and D. monostyla and D. crassipes cluster with its congeners, which confirms their generic assignments.


Assuntos
Cilióforos , Animais , China , DNA de Protozoário , DNA Ribossômico , Filogenia
7.
Zootaxa ; 4648(2): zootaxa.4648.2.11, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31716955

RESUMO

Epibiosis is common among ciliates and crustaceans because the calcified surface of the crustacean body offers a suitable site for colonization by the epibiont. Suctoria are among the most common epibiont ciliate groups of freshwater decapod crustaceans. The aim of this study is to increase knowledge of suctorians as epibionts of freshwater decapod crustaceans of the families Cambaridae and Pseudothelphusidae. Crustaceans were collected from three rivers and one pond in Chiapas, Mexico. Six species of suctorian epibionts were recorded: Acineta tuberosa, Podophrya maupasi, P. sandi, Tokophrya cyclopum, T. quadripartita and Trichophrya epistylidis. This is the first record of ciliate epibionts on members of family Pseudothelphusidae (represented by Phrygiopilus montebelloensis and Raddaus bocourti), and the first record of suctorians epibionts on Procambarus (Austrocambarus) sp. (Cambaridae).


Assuntos
Cilióforos , Cinetofragminóforos , Animais , Astacoidea , Água Doce , México
8.
Zootaxa ; 4646(2): zootaxa.4646.2.11, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31717022

RESUMO

Species composition and distribution of hindgut ciliates were investigated in the feces of 20 thoroughbred mares in Kentucky, USA. Thirty-three species and six morphotypes belonging to 21 genera were identified. The average density of hindgut ciliates in mares was 13.5 ± 13.7 × 104 cells ml-1, whereas mean number of ciliate species per host was 14.4 ± 5.3. Bundleia nana, B. elongata, B. piriformis, Blepharoconus hemiciliatus, Holophryoides ovalis, H. macrotricha, Blepharoprosthium polytrichum, Prorodonopsis coli, Paraisotrichopsis composita, Blepharocorys microcorys, and Ochoterenaia appendiculata were the first identified species in horses inhabited in USA. Scanning electron microscopic images of Holophryoides macrotricha, Paraisotrichopsis composita, Cycloposthium dentiferum m. corrugatum, C. edentatum m. edentatum, C. edentatum m. scutigerum, Tetratoxum parvum m. parvum, T. parvum m. sulcatum, T. excavatum m. excavatum, Allantosoma intestinale, and Arcosoma brevicorniger were studied. Binary fission in Polymorphella ampulla was also studied.


Assuntos
Cilióforos , Abdome , Animais , Fezes , Feminino , Cavalos , Kentucky , Microscopia Eletrônica de Varredura
9.
Zootaxa ; 4612(4): zootaxa.4612.4.2, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31717038

RESUMO

The article presents a review of the literature on known representatives of the genus Lecanophryella containing general characteristics of the members of this genus, information on morphology and data on distribution. Diagnostic characters of L. satyanandani is emended based on material collected from a new locality. A new species, Lecanophryella indica as epibiont on the body surface of cyclopoid copepod from the Zuari estuary, west coast of India is also described.


Assuntos
Cilióforos , Copépodes , Animais , Índia
10.
Zootaxa ; 4609(3): zootaxa.4609.3.9, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31717099

RESUMO

In this study, Frontonia leucas, Frontonia acuminata, Frontonia angusta, and Frontonia anatolica species isolated from aquatic environments of Van in Turkey were investigated in detail using morphological, morphometrical, and molecular methods. Although there were minor differences, the Frontonia populations were morphologically similar to the other previously reported populations of the 4 species. Frontonia leucas differed from the other populations by the following combination of characters: about 200 somatic and only 3 vestibular kineties, and a single micronucleus. The Turkish population of Frontonia acuminata had just 4 vestibular kineties and the large micronucleus was always located to the anterior of the carrot-shaped macronucleus. The ratio of the oral apparey size to the cell size of Frontonia angusta in this study was about 18%, with 3 vestibular kineties, and 1 excretory pore. Phylogenetic trees based on small-subunit rRNA gene sequences were constructed using Bayesian inference and maximum-likelihood. Frontonia anatolica was more closely related to Apofrontonia dohrni and Paramecium spp. than to its congeners, while F. acuminata, like F. terricola, was also more closely related to the family Stokesiidae. The results indicated that Frontonia is a non-monophyletic genus consisting of 3 groups. We presented the systematic relationships of the genera and families of Peniculida with new data of genus Frontonia herein.


Assuntos
Cilióforos , Animais , Teorema de Bayes , China , DNA de Protozoário , DNA Ribossômico , Genes de RNAr , Filogenia , Análise de Sequência de DNA , Turquia
11.
Harmful Algae ; 89: 101654, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31672223

RESUMO

Dinoflagellate species of Dinophysis, in particular D. acuminata and D. acuta, produce lipophilic toxins that pose a threat to human health when concentrated in shellfish and jeopardize shellfish exploitations in western Europe. In northwestern Iberia, D. acuminata has a long growing season, from spring to early autumn, and populations develop as soon as shallow stratification forms when the upwelling season begins. In contrast, D. acuta blooms in late summer, when the depth of the pycnocline is maximal and upwelling pulses are moderate. In situ observations on the hydrodynamic regimes during the two windows of opportunity for Dinophysis species led us to hypothesize that D. acuta should be more sensitive to turbulence than D. acuminata. To test this hypothesis, we studied the response of D. acuminata and D. acuta to three realistic turbulence levels low (LT), ε ≈ 10-6 m2 s-3; medium (MT), ε ≈ 10-5 m2 s-3 and high (HT), ε ≈ 10-4 m2 s-3generated by Turbogen, a highly reproducible, computer-controlled system. Cells of both species exposed to LT and MT grew at rates similar to the controls. Marked differences were found in the response to HT: D. acuminata grew slowly after an initial lag phase, whereas D. acuta cell numbers declined. Results from this study support the hypothesis that turbulence may play a role in shaping the spatio-temporal distribution of individual species of Dinophysis. We also hypothesize that, in addition to cell disturbance affecting division, sustained high shear generated by microturbulence may cause a decline in Dinophysis numbers due to decreased densities of ciliate prey.


Assuntos
Cilióforos , Dinoflagelados , Europa (Continente) , Estações do Ano , Frutos do Mar
12.
Zootaxa ; 4695(6): zootaxa.4695.6.5, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31719326

RESUMO

Species distribution and composition of the ciliates found in the ruminal contents of 15 domestic sheep (Ovis aries) living in Kastamonu, Turkey, were investigated. Twenty-four species and 8 morphotypes belonging to 10 genera were identified. The density of the rumen ciliates in sheep was 108.2 (± 150.8) × 104 cells ml-1, and the mean number of ciliate species per host was 10.7 ± 4.6. Among the ciliate species identified, Dasytricha ruminantium was the most abundant, with a prevalence of 93.3%, whereas Diplodinium quinquespinosum, Eudiplodinium rostratum, and Metadinium tauricum were detected in only one animal (6.7% prevalence). D. quinquespinosum, Eudiplodinium rostratum, and Entodinium simulans m. dubardi were detected for the first time in sheep from Turkey. This is the first report of the presence of D. quinquespinosum in the rumen of ruminants in Turkey. The infraciliature of D. quinquespinosum, Metadinium affine, and M. tauricum (Entodiniomorphida, Ophryoscolecidae) was investigated. D. quinquespinosum and M. affine had Diplodinium-type infraciliature, whereas M. tauricum possessed Metadinium medium-type infraciliature.


Assuntos
Cilióforos , Rúmen , Animais , Ovinos , Turquia
13.
Zootaxa ; 4695(4): zootaxa.4695.4.5, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31719343

RESUMO

The article deals with the report of 5 suctorians viz. Lecanophryella satyanandani (Santhakumari, 1986), Paracineta karunakarani Santhakumari, 1986, Ephelota gemmipara (Hertwig, 1876), Acineta foetida Maupas, 1881 and Pelagacineta sp. on marine pelagic ostracods Cypridina dentata (Müller, 1906) from new localities of the Arabian Sea. Diagnostic characters of Paracineta karunakarani are emended. Ephelota gemmipara (Hertwig, 1876) and Acineta foetida Maupas, 1881 are reported here for the first time on planktonic marine ostracods. Pelagacineta sp. is reported for the first time as epibiont on ostracods and from the Indian Ocean.


Assuntos
Cilióforos , Crustáceos , Animais , Oceano Índico , Plâncton
14.
PLoS Negl Trop Dis ; 13(10): e0007742, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589617

RESUMO

Paracoccidioides spp. are thermodimorphic fungi that cause a neglected tropical disease (paracoccidioidomycosis) that is endemic to Latin America. These fungi inhabit the soil, where they live as saprophytes with no need for a mammalian host to complete their life cycle. Despite this, they developed sophisticated virulence attributes allowing them not only to survive in host tissues but also to cause disease. A hypothesis for selective pressures driving the emergence or maintenance of virulence of soil fungi is their interaction with soil predators such as amoebae and helminths. We evaluated the presence of environmental amoeboid predators in soil from armadillo burrows where Paracoccidioides had been previously detected and tested if the interaction of Paracoccidioides with amoebae selects for fungi with increased virulence. Nematodes, ciliates, and amoebae-all potential predators of fungi-grew in cultures from soil samples. Microscopical observation and ITS sequencing identified the amoebae as Acanthamoeba spp, Allovahlkampfia spelaea, and Vermamoeba vermiformis. These three amoebae efficiently ingested, killed and digested Paracoccidioides spp. yeast cells, as did laboratory adapted axenic Acanthamoeba castellanii. Sequential co-cultivation of Paracoccidioides with A. castellanii selected for phenotypical traits related to the survival of the fungus within a natural predator as well as in murine macrophages and in vivo (Galleria mellonella and mice). These changes in virulence were linked to the accumulation of cell wall alpha-glucans, polysaccharides that mask recognition of fungal molecular patterns by host pattern recognition receptors. Altogether, our results indicate that Paracoccidioides inhabits a complex environment with multiple amoeboid predators that can exert selective pressure to guide the evolution of virulence traits.


Assuntos
Amoeba/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Paracoccidioides/fisiologia , Microbiologia do Solo , Acanthamoeba castellanii/fisiologia , Amoeba/citologia , Amoeba/microbiologia , Animais , Tatus , Cilióforos , Técnicas de Cocultura , Modelos Animais de Doenças , Fungos , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nematoides , Paracoccidioides/patogenicidade , Paracoccidioidomicose/microbiologia , Fagocitose , Solo , Virulência , Fatores de Virulência/fisiologia
15.
Eur J Protistol ; 71: 125629, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31520848

RESUMO

The morphology and ontogenesis of a novel stylonychid ciliate, Tetmemena pustulata indica nov. subspec., were investigated using live observation and protargol preparation. The new subspecies was isolated from a water sample collected from the Thane Creek, Mumbai, India. At first glance, T. pustulata indica looked very similar in morphology and ontogenesis to the well-known Tetmemena pustulata, however, on detailed investigation some non-overlapping features in the ciliature were identified, i.e., the numbers of cirri in marginal rows, adoral membranelles, and bristles in dorsal kineties. These morphometric differences justified the separation at subspecies level. Furthermore, the resting cysts are different, i.e., with smooth external layer in T. pustulata indica whereas spinous in the nominotypical subspecies T. pustulata pustulata. The Venezuelan population of T. pustulata described by Foissner corresponds very well with the Indian population in the ciliature; however, the information on the resting cyst is lacking for the former. Our study presents an example of a cyst subspecies among hypotrich ciliates, and thus extends the concept which has been mainly reported for spathidiids.


Assuntos
Cilióforos/classificação , Cilióforos/citologia , Rios/parasitologia , Índia , Especificidade da Espécie
16.
Fish Shellfish Immunol ; 94: 661-674, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521785

RESUMO

The yellow drum Nibea albiflora is less susceptible to Cryptocaryon irritans infection than is the case with other marine fishes such as Larimichthys crocea, Lateolabrax japonicus, and Pagrus major. To investigate further their resistance mechanism, we infected the N. albiflora with the C. irritans at a median lethal concentration of 2050 theronts/g fish. The skins of the infected and the uninfected fishes were sampled at 24 h and 72 h followed by an extensive analysis of metabolism. The study results revealed that there were 2694 potential metabolites. At 24 h post-infection, 12 metabolites were up-regulated and 17 were down-regulated whereas at 72 h post-infection, 22 metabolites were up-regulated and 26 were down-regulated. Pathway enrichment analysis shows that the differential enriched pathways were higher at 24 h with 22 categories and 58 subcategories (49 up, 9 down) than at 72 h whereby the differential enriched pathways were 6 categories and 8 subcategories (4 up, 4 down). In addition, the principal component analysis (PCA) plot shows that at 24 h the metabolites composition of infected group were separately clustered to uninfected group while at 72 h the metabolites composition in infected group were much closer to uninfected group. This indicated that C. irritans caused strong metabolic stress on the N. albiflora at 24 h and restoration of the dysregulated metabolic state took place at 72 h of infection. Also, at 72 h post infection a total of 17 compounds were identified as potential biomarkers. Furthermore, out of 2694 primary metabolites detected, 23 metabolites could be clearly identified and semi quantified with a known identification number and assigned into 66 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Most of the enriched KEGG pathways were mainly from metabolic pathway classes, including the metabolic pathway, biosynthesis of secondary metabolites, taurine and hypotaurine metabolism, purine metabolism, linoleic acid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis. Others were glyoxylate and dicarboxylate metabolism, glutathione metabolism, and alanine, aspartate, and glutamate metabolism. Moreover, out of the identified metabolites, only 6 metabolites were statistically differentially expressed, namely, L -glutamate (up-regulated) at 24 h was important for energy and precursor for other glutathiones and instruments of preventing oxidative injury; 15-hydroxy- eicosatetraenoic acid (15-HETE), (S)-(-)-2-Hydroxyisocaproic acid, and adenine (up-regulated) at 72 h were important for anti-inflammatory and immune responses during infection; others were delta-valerolactam and betaine which were down-regulated compared to uninfected group at 72 h, might be related to immure responses including stimulation of immune system such as production of antibodies. Our results therefore further advance our understanding on the immunological regulation of N. albiflora during immune response against infections as they indicated a strong relationship between skin metabolome and C. irritans infection.


Assuntos
Infecções por Cilióforos/veterinária , Doenças dos Peixes/imunologia , Imunidade Inata/imunologia , Metaboloma/imunologia , Perciformes , Pele/imunologia , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/parasitologia
17.
Int. microbiol ; 22(3): 355-361, sept. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184842

RESUMO

The effect of oxygen on anaerobic protozoa was studied in anaerobic batch reactors inoculated with sludge and protozoa cultures. Among the protozoa genera, Metopus, Brachonella, Plagiopyla, Trepomonas, and Vanella were more sensitive to oxygen compared to other genera. Protozoa genera Menoidium, Rhynchomonas, Cyclidium, Spathidium, and Amoeba were found to survive under aerobic conditions, and the growth rate was slightly higher or similar to anaerobic condition. O2 tension resulted in the loss of free and endosymbiotic methanogens in anaerobic system, while methanogens were observed inside the protozoan cysts. Survival of anaerobic protozoa declined considerably when the O2 tension exceeded 1% atm. sat. and showed chemosensory behavior in response to O2 exposure. Superoxide dismutase activity was detected in survived protozoa cells under O2 tension. Facultative anaerobic protozoa with SOD activity can provide a mechanism to overcome possible occurrence of oxygen toxicity in the treatment of wastewater in anaerobic reactor


No disponible


Assuntos
Amoeba/efeitos dos fármacos , Cilióforos/efeitos dos fármacos , Meios de Cultura/química , Euglênidos/efeitos dos fármacos , Kinetoplastida/efeitos dos fármacos , Oxigênio/toxicidade , Aerobiose , Amoeba/crescimento & desenvolvimento , Amoeba/metabolismo , Anaerobiose , Reatores Biológicos/parasitologia , Cilióforos/crescimento & desenvolvimento , Cilióforos/metabolismo , Euglênidos/crescimento & desenvolvimento , Euglênidos/metabolismo , Kinetoplastida/crescimento & desenvolvimento , Kinetoplastida/metabolismo , Metano/metabolismo , Sobrevivência Celular
18.
Fish Shellfish Immunol ; 93: 863-870, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422178

RESUMO

Interleukins (ILs) are a subgroup of cytokines, which are molecules involved in the intercellular regulation of the immune system. These cytokines have been extensively studied in mammalian models, but systematic analyses of fish are limited. In the current study, 3 IL genes from golden pompano (Trachinotus ovatus) were characterized. The IL-1ß protein contains IL-1 family signature motif, and four long helices (αA - αD) in IL-11 and IL-34, which were well conserved. All 3 ILs clustered phylogenetically with their respective IL relatives in mammalian and other teleost species. Under normal physiological conditions, the expression of IL-1ß, IL-11, and IL-34 were detected at varied levels in the 11 tissues examined. Most of the 3 ILs examined were highly expressed in liver, spleen, kidney, gill, or skin. Following pathogenic bacterial, viral, or parasitic challenge, IL-1ß, IL-11, and IL-34 exhibited distinctly different expression profiles in a time-, tissue-, and pathogen-dependent manner. In general, IL-1ß was expressed at higher levels following challenge with all pathogens examined than was observed for IL-11 and IL-34. Furthermore, Streptococcus agalactiae and Cryptocaryon irritans caused higher levels of IL-1ß and IL-11 expression than Vibrio harveyi and viral nervous necrosis virus (VNNV). The increased expression of IL-34 caused by VNNV and C. irritans were higher than that caused by V. harveyi and S. agalactiae. These results suggest that these 3 ILs in T. ovatus may play different effect pathogen type specific responses.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Perfilação da Expressão Gênica/veterinária , Interleucina-11/genética , Interleucina-11/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucinas/genética , Interleucinas/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
19.
Nature ; 571(7766): 560-564, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292551

RESUMO

The biophysical relationships between sensors and actuators1-5 have been fundamental to the development of complex life forms. Swimming organisms generate abundant flows that persist in aquatic environments6-13, and responding promptly to external stimuli is key to survival14-19. Here we present the discovery of 'hydrodynamic trigger waves' in cellular communities of the protist Spirostomum ambiguum that propagate-in a manner similar to a chain reaction20-22-hundreds of times faster than their swimming speed. By coiling its cytoskeleton, Spirostomum can contract its long body by 60% within milliseconds23, experiencing accelerations that can reach forces of 14g. We show that a single cellular contraction (the transmitter) generates long-ranged vortex flows at intermediate Reynolds numbers that can, in turn, trigger neighbouring cells (the receivers). To measure the sensitivity to hydrodynamic signals in these receiver cells, we present a high-throughput suction-flow device for probing mechanosensitive ion channels24 by back-calculating the microscopic forces on the cell membrane. We analyse and quantitatively model the ultra-fast hydrodynamic trigger waves in a universal framework of antenna and percolation theory25,26, and reveal a phase transition that requires a critical colony density to sustain collective communication. Our results suggest that this signalling could help to organize cohabiting communities over large distances and influence long-term behaviour through gene expression (comparable to quorum sensing16). In more immediate terms, because contractions release toxins27, synchronized discharges could facilitate the repulsion of large predators or immobilize large prey. We postulate that numerous aquatic organisms other than protists could coordinate their behaviour using variations of hydrodynamic trigger waves.


Assuntos
Comunicação Celular , Cilióforos/citologia , Cilióforos/fisiologia , Hidrodinâmica , Natação/fisiologia , Movimentos da Água , Animais , Organismos Aquáticos/citologia , Organismos Aquáticos/genética , Organismos Aquáticos/fisiologia , Biofísica , Cilióforos/genética , Citoesqueleto/fisiologia , Comportamento Predatório , Reologia , Fatores de Tempo
20.
Fish Shellfish Immunol ; 92: 690-697, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276788

RESUMO

Macrophage expressed gene 1 (Mpeg1) is a molecule that can form pores and destroy the cell membrane of invading pathogens. In this study, we identified two Mpeg1 isoforms from the orange-spotted grouper (Epinephelus coioides) and named them EcMpeg1a and EcMpeg1b. Predicted proteins of the two EcMpeg1s contained a signal peptide, a conserved membrane attack complex/perforin (MACPF) domain, a transmembrane segment, and an intracellular region. Sequence alignment demonstrated that two EcMpeg1 proteins share a high sequence identity with that of other teleosts. Tissue distribution analysis showed that EcMpeg1s were expressed in all tissues tested in healthy grouper, with the highest expression in the head kidney and spleen. After infection with the ciliate parasite Cryptocaryon irritans, expression of the two EcMpeg1s was significantly upregulated in the spleen and gills. Furthermore, the recombinant EcMpeg1a showed antiparasitic and antibacterial activity against Gram-negative and -positive bacteria, whereas EcMpeg1b had an inhibitory effect only against Gram-positive bacteria. These results indicated that EcMpeg1s play an important role in the host response against invading pathogens.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Sequência de Aminoácidos , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Proteínas de Membrana/química , Filogenia , Alinhamento de Sequência/veterinária
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