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1.
Insect intestinal tracts harbor several novel, deep-rooting clades of as-yet-uncultivated bacteria whose biology is typically completely unknown. Here, we report the isolation of the first representative of the termite group 1 (TG1) phylum from sterile-filtered gut homogenates of a humivorous scarab beetle larva. Strain Pei191T is a mesophilic, obligately anaerobic ultramicrobacterium with a gram-negative cell envelope. Cells are typically rod shaped, but cultures are pleomorphic in all growth phases (0.3 to 2.5 μm long and 0.17 to 0.3 μm wide). The isolate grows heterotrophically on sugars and ferments d-galactose, d-glucose, d-fructose, d-glucosamine, and N-acetyl-d-glucosamine to acetate, ethanol, hydrogen, and alanine as major products but only if amino acids are present in the medium. PCR-based screening and comparative 16S rRNA gene sequence analysis revealed that strain Pei191T belongs to the “intestinal cluster,” a lineage of hitherto uncultivated bacteria present in arthropod and mammalian gut systems. It is only distantly related to the previously described so-called “endomicrobia” lineage, which comprises mainly uncultivated endosymbionts of termite gut flagellates. We propose the name “Elusimicrobium minutum” gen. nov., sp. nov. (type strain, Pei191T = ATCC BAA-1559T = JCM 14958T) for the first isolate of this deep-branching lineage and the name “Elusimicrobia” phyl. nov. for the former TG1 phylum.Insect intestinal tracts harbor an enormous diversity of as-yet-uncultivated bacteria that are characterized only by their 16S rRNA gene sequences and whose biology is typically completely obscure (9, 17, 49). As in other environments (45), many of these sequences form deep-branching phylogenetic lineages that do not contain a single isolate (18, 28). One of these lineages is the termite group 1 (TG1), which was originally discovered by Ohkuma and Kudo (37) and recognized as a phylum-level group (candidate division) by Hugenholtz et al. (20). TG1 bacteria form a major proportion of the microbial community in the hindgut of lower termites (17, 69), where they inhabit the cytoplasm of the intestinal flagellates (38, 53). These so-called “endomicrobia” are specific for the respective flagellate species (21) and, at least in the case of “Candidatus Endomicrobium trichonymphae,” are cospeciating with their flagellate host (22).However, the TG1 phylum also comprises several other deep-rooting lineages (>15% 16S rRNA gene sequence divergence). They are present in a variety of environments, including soils, sediments, and intestinal tracts (14). One of these lineages, the “intestinal cluster,” comprises sequences originating exclusively from intestinal habitats, including the termite gut, but is only distantly related to the lineage comprising the “endomicrobia” (14). Here, we report the isolation of a member of the intestinal cluster from the hindgut of a humivorous scarab beetle larva and its physiological and ultrastructural characterization. We propose a new species, “Elusimicrobium minutum” gen. nov. sp. nov., and define the phylogenetic framework for the first cultivated representative of the TG1 phylum.  相似文献   

2.
In 2007, a novel, putatively photosynthetic picoeukaryotic lineage, the ‘picobiliphytes’, with no known close eukaryotic relatives, was reported from 18S environmental clone library sequences and fluorescence in situ hybridization. Although single cell genomics later showed these organisms to be heterotrophic rather than photosynthetic, until now this apparently widespread group of pico-(or nano-)eukaryotes has remained uncultured and the organisms could not be formally recognized. Here, we describe Picomonas judraskeda gen. et sp. nov., from marine coastal surface waters, which has a ‘picobiliphyte’ 18S rDNA signature. Using vital mitochondrial staining and cell sorting by flow cytometry, a single cell-derived culture was established. The cells are biflagellate, 2.5–3.8×2–2.5 µm in size, lack plastids and display a novel stereotypic cycle of cell motility (described as the “jump, drag, and skedaddle”-cycle). They consist of two hemispherical parts separated by a deep cleft, an anterior part that contains all major cell organelles including the flagellar apparatus, and a posterior part housing vacuoles/vesicles and the feeding apparatus, both parts separated by a large vacuolar cisterna. From serial section analyses of cells, fixed at putative stages of the feeding cycle, it is concluded that cells are not bacterivorous, but feed on small marine colloids of less than 150 nm diameter by fluid-phase, bulk flow endocytosis. Based on the novel features of cell motility, ultrastructure and feeding, and their isolated phylogenetic position, we establish a new phylum, Picozoa, for Picomonas judraskeda, representing an apparently widespread and ecologically important group of heterotrophic picoeukaryotes, formerly known as ‘picobiliphytes’.  相似文献   

3.
Jaskuła R 《ZooKeys》2011,(100):487-502
The tiger beetle fauna of the Balkan Peninsula is one of the richest in Europe and includes 19 species or 41% of the European tiger beetle fauna. Assembled by their biogeographical origins, the Balkan tiger beetle species fall into 14 different groups that include, Mediterranean, Middle Oriental, Central Asiatic, Euro-Siberian, South and East European, Pannonian-Sarmatian, West Palaearctic, Turano-European and Afrotropico Indo-Mediterranean species. The Mediterranean Sclerophyl and the Pontian Steppe are the Balkan biogeographical provinces with the highest species richness, while the Balkan Highlands has the lowest Cicindelidae diversity. Most species are restricted to single habitat types in lowland areas of the Balkan Peninsula and only Calomera aulica aulica and Calomera littoralis nemoralis occur in respectively 3 and 4 different types of habitat. About 60% of all Balkan Cicindelidae species are found in habitats potentially endangered by human activity.  相似文献   

4.
The genus Planinasus Cresson is revised and includes 18 extant and one fossil species. We clarify the status of the three previously described species and describe 15 new species as follows (type locality in parenthesis): Planinasus aenigmaticus (Colombia. Bogota: Bogota (04°35.8''N, 74°08.8''W)), Planinasus neotropicus (Panama. Canal Zone: Barro Colorado Island (09°09.1''N, 79°50.8''W)), Planinasus kotrbae (Ecuador. Orellana: Rio Tiputini Biodiversity Station (0°38.2''S, 76°08.9''W)), Planinasus miradorus (Brazil. Maranhão: Parque Estadual Mirador, Base da Geraldina (06°22.2''S, 44°21.8''W)), Planinasus tobagoensis (Trinidad and Tobago. Tobago. St. John: Parlatuvier (11°17.9''N, 60°39''W)), Planinasus xanthops (Ecuador. Orellana: Rio Tiputini Biodiversity Station (0°38.2''S, 76°8.9''W)), Planinasus argentifacies (Peru. Madre de Dios: Río Manu, Pakitza (11°56.6''S, 71°16.9''W; 250 m)), Planinasus insulanus (Dominican Republic. La Vega: near Jarabacoa, Salto Guasara (19°04.4''N, 70°42.1''W, 680 m)), Planinasus nigritarsus (Guyana. Conservation of Ecological Interactions and Biotic Associations (CEIBA; ca. 40 km S Georgetown; 06°29.9''N, 58°13.1''W)), Planinasus atriclypeus (Brazil. Rio de Janeiro: Rio de Janeiro, Floresta da Tijuca (22°57.6''S, 43°16.4''W)), Planinasus atrifrons (Bolivia. Santa Cruz: Ichilo, Buena Vista (4-6 km SSE; Hotel Flora y Fauna; 17°29.95''S, 63°33.15''W; 4-500 m)), P. flavicoxalis (West Indies. Dominica. St. David: 1.6 km N of junction of roads to Rosalie and Castle Bruce (15°23.8''N, 61°18.6''W)), Planinasus mcalpineorum (Mexico. Chiapas: Cacahoatan (7 km N; 15°04.1''N, 92°07.4''W)), Planinasus nigrifacies (Brazil. São Paulo: Mogi das Cruzes, Serra do Itapeti (23°31.5''S, 46°11.2''W)), Planinasus obscuripennis (Peru. Madre de Dios: Río Manu, Erika (near Salvación; 12°50.7''S, 71°23.3''W; 550 m)). In addition to external characters, we also describe and illustrate structures of the male terminalia and for Planinasus kotrbae sp. n., the internal female reproductive organs. Detailed locality data and distribution maps for all species are provided. For perspective and to facilitate genus-group and species-group recognition, the family Periscelididae and subfamily Stenomicrinae are diagnosed and for the latter, a key to included genera is provided.  相似文献   

5.
Six species of Gastrocopta have been identified from the Pilbara region, Western Australia, by means of comparative analyses of shell and mtDNA variation. Three of these species, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta servilis, have been recorded in the Pilbara for the first time. Gastrocopta sp. CW1 is probably new to science and might be endemic to the region. By contrast, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta mussoni are shown to be widespread.  相似文献   

6.
A new genus of Isotomidae, Bellisotoma gen. n., is described. The new genus is a member of the Proisotoma genus complex and is characterized by a combination of having a bidentate mucro with wide dorsal lamellae that join clearly before the end of mucronal axis without forming a tooth and one strong ventral rib with basal notch that articulates with dens; having abundant chaetotaxy on both faces of dens; and abundant tergal sensilla. Bellisotoma gen. n. shows a furcula adapted to a neustonic mode of life, and may be a Isotopenola-like derivative adapted to neustonic habitats. Subisotoma joycei Soto-Adames & Giordano, 2011 and Ballistura ewingi James, 1933 are transferred to the new genus.  相似文献   

7.
Duvalius (sg. Neoduvalius) gejzadunayi sp. n. from Pećina u Dubokom potoku cave ( Donje Biševo village near Rožaje, Montenegro), the first known representative of this subgenus from the territory of Montenegro is described, illustrated and compared with the related species of the subgenus Neoduvalius Müller, 1913. This new species is characterised by depigmented, medium sized body, totally reduced eyes, deep and complete frontal furrows, 3–4 pairs of discal setae in third elytral stria, as well as by the shape of aedeagus. Data on the distribution and the ecology of this remarkable species, as well as a check-list of the subgenus Neoduvalius are also provided. Recently described genera Serboduvalius Ćurčić, S. B. Pavićević & Ćurčić, B.P.M., 2001, Rascioduvalius Ćurčić, S. B. Brajković, Mitić & Ćurčić, B.P.M., 2003, Javorella Ćurčić, S. B. Brajković, Ćurčić, B.P.M. & Mitić, 2003 and Curcicia Ćurčić, S. B. & Brajković, 2003 are regarded as junior synonyms of the genus Duvalius Delarouzée.  相似文献   

8.
Cell death can be divided into the anti-inflammatory process of apoptosis and the pro-inflammatory process of necrosis. Necrosis, as apoptosis, is a regulated form of cell death, and Poly-(ADP-Ribose) Polymerase-1 (PARP-1) and Receptor-Interacting Protein (RIP) 1/3 are major mediators. We previously showed that absence or inhibition of PARP-1 protects mice from nephritis, however only the male mice. We therefore hypothesized that there is an inherent difference in the cell death program between the sexes. We show here that in an immune-mediated nephritis model, female mice show increased apoptosis compared to male mice. Treatment of the male mice with estrogens induced apoptosis to levels similar to that in female mice and inhibited necrosis. Although PARP-1 was activated in both male and female mice, PARP-1 inhibition reduced necrosis only in the male mice. We also show that deletion of RIP-3 did not have a sex bias. We demonstrate here that male and female mice are prone to different types of cell death. Our data also suggest that estrogens and PARP-1 are two of the mediators of the sex-bias in cell death. We therefore propose that targeting cell death based on sex will lead to tailored and better treatments for each gender.  相似文献   

9.
10.
The female of Balmacedanigrosecta Mello-Leitão, 1945 is described and illustrated for the first time. In addition, this paper further illustrates the male, and provides the first known observations on the natural history of this species, including habitat, cohabitation, and prey capturedata.  相似文献   

11.
Paraportanus longispinus,, a new leafhopper species from Roraima and Amazonas States, North Brazil, is described and illustrated. The new species can be recognized by the male genital features, especially the distal third of ventral margin of the pygofer with a dentiform short process; plates distinctly longer than pygofer, extending posteriorly beyond pygofer by approximately 1/3 of their length and aedeagus with one pair of spiniform process long crossed and directed ventrally. A checklist and key to males of all known Paraportanus species is provided.  相似文献   

12.
We describe a new species of Imantodes from the Chocó region of northwestern Ecuador. The new species differs most significantly from all other congeners in lacking a loreal scale. We analyze the phylogenetic relationships among species of Imantodes based on two mitochondrial genes, and postulate that the new species and Imantodes lentiferus are sister taxa. A key to the species of Imantodes from Ecuador is presented.  相似文献   

13.
The mechanisms by which epithelial cells regulate clathrin-mediated endocytosis (CME) of transferrin are poorly defined and generally viewed as a constitutive process that occurs continuously without regulatory constraints. In this study, we demonstrate for the first time that endocytosis of the transferrin receptor is a regulated process that requires activated Src kinase and, subsequently, phosphorylation of two important components of the endocytic machinery, namely, the large GTPase dynamin 2 (Dyn2) and its associated actin-binding protein, cortactin (Cort). To our knowledge these findings are among the first to implicate an Src-mediated endocytic cascade in what was previously presumed to be a nonregulated internalization process.Iron is an essential element for all mammalian organisms that plays essential roles in hemoglobin and myoglobin production (23). Altered iron transport can lead to disease states such as hemochromatosis (23), anemia (5, 23), and neuronal disorders (23). The transferrin receptor (TfR) is an important component of iron regulation in cells. There are two distinct TfRs in humans sharing 45% identity that are homodimeric and bind iron-associated transferrin (Tf) at markedly different affinities (26). While significant attention has been paid toward understanding the basic endocytic machinery that supports the efficient internalization and recycling of the TfR1 and its associated iron-bound ligand, it has been assumed that this transport process is constitutive in nature. This is in direct contrast to the highly regulated internalization pathway used by members of the receptor tyrosine kinase family (RTKs) and the family of G-coupled protein receptors (GPCRs) that utilize phosphorylation and/or ubiquination as signaling modules to regulate internalization.To test if TfR1 internalization might be regulated in a similar fashion, we focused on two essential components of the endocytic machinery: the large GTPase Dyn2 that mediates endocytic vesicle scission (35) and Cort that binds to Dyn2 via an SH3-PRD interaction and has been postulated to regulate actin dynamics to facilitate vesicle invagination and release (36, 40). Both Dyn2 and Cort have shown to be phosphorylated in vivo and in vitro by a variety of kinases (51, 58). Dyn1 interacts with (17) and is phosphorylated by Src in neuronal cells and in other excitable cells in response to activation of GPCRs and epidermal growth factor (EGF) (1, 2). While the Src phosphorylation motifs of dynamin are conserved in the epithelial expressed form of Dyn2, it is unclear if Dyn2 is phosphorylated in response to ligands that induce clathrin-based endocytosis.Cort possesses a series of C-terminal tyrosines that are heavily Src-phosphorylated and implicated in regulating actin remodeling during cell motility (20). In this study, we demonstrate that addition of Tf to cultured epithelial cells results in an internalization of the TfR1 mediated by a Src kinase-dependent phosphoactivation of the Dyn2-Cort-based endocytic machinery. In support of these findings, dominant negative forms of c-Src kinase, when expressed in a hepatocyte-derived cell line (Clone 9), attenuate Tf internalization. Remarkably, cells exposed to Tf showed a 3- to 4-fold increase in Dyn2 and Cort phosphorylation compared to that shown by untreated cells, an increase exceeding that observed in cells treated with EGF. These findings provide new insights into the regulation of what was thought to be a constitutive endocytic process.  相似文献   

14.
15.
Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with Sinularia maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented.  相似文献   

16.
The Lispe longicollis species-group is revised. Lispe ethiopicasp. n. is described. The following 3 new synonyms are established: Lispe assimilis Wiedemann, 1824 (syn: cyrtoneurina Stein, 1900 and modesta Stein, 1913); Lispe manicata Wiedemann, 1830 (syn: forficata Kurahashi & Shinonaga, 2009). Female of Lispe microptera Seguy, 1937 is described for the first time. Identification key for known Eurasian and African species is given.  相似文献   

17.
Migratory routes and wintering grounds can have important fitness consequences, which can lead to divergent selection on populations or taxa differing in their migratory itinerary. Collared (Ficedula albicollis) and pied (F. hypoleuca) flycatchers breeding in Europe and wintering in different sub-Saharan regions have distinct migratory routes on the eastern and western sides of the Sahara desert, respectively. In an earlier paper, we showed that hybrids of the two species did not incur reduced winter survival, which would be expected if their migration strategy had been a mix of the parent species'' strategies potentially resulting in an intermediate route crossing the Sahara desert to different wintering grounds. Previously, we compared isotope ratios and found no significant difference in stable-nitrogen isotope ratios (δ 15N) in winter-grown feathers between the parental species and hybrids, but stable-carbon isotope ratios (δ 13C) in hybrids significantly clustered only with those of pied flycatchers. We followed up on these findings and additionally analyzed the same feathers for stable-hydrogen isotope ratios (δ 2H) and conducted spatially explicit multi-isotope assignment analyses. The assignment results overlapped with presumed wintering ranges of the two species, highlighting the efficacy of the method. In contrast to earlier findings, hybrids clustered with both parental species, though most strongly with pied flycatcher.  相似文献   

18.
19.
20.
Seven new species of the Neotropical hairstreak genus Oenomaus are described: Oenomaus mancha Busby & Faynel, sp. n. (type locality Ecuador); Oenomaus gwenish Robbins & Faynel, sp. n. (type locality Panama); Oenomaus lea Faynel & Robbins, sp. n. (type locality Ecuador); Oenomaus myrteana Busby, Robbins & Faynel, sp. n. (type locality Ecuador); Oenomaus mentirosa Faynel & Robbins, sp. n. (type locality Peru); Oenomaus andi Busby & Faynel, sp. n. (type locality Ecuador) and Oenomaus moseri Robbins & Faynel, sp. n. (type locality Brazil, Santa Catarina). For each new Oenomaus species, we present diagnostic characters and notes on its habitat and biology. We illustrate adults, genitalia, and distribution. New distributional and biological data are presented for 21 previously described Oenomaus species. Oenomaus melleus guyanensis Faynel, 2008 is treated as a new synonym of Oenomaus melleus melleus (Druce, 1907). Females are described and associated with males for ten species using a variety of factors, including mitochondrial COI DNA “barcode” sequences. We summarize the reasons why the number of recognized Oenomaus species has grown in the past decade from one species to 28 species. Finally, we overview the habitats that Oenomaus species occupy and note that the agricultural pest on Annonaceae, Oenomaus ortygnus, is the only Oenomaus species that regularly occurs in greatly disturbed habitats.  相似文献   

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