We share whole genome sequences of six strains from the Ralstonia solanacearum species complex, a diverse group of beta-Proteobacteria that cause plant vascular wilt diseases. Using single-molecule real-time (SMRT) technology, we sequenced and assembled full genomes of Rs5 and UW700, two phylotype IA-sequevar 7 (IIA-7) strains from the southeastern US that are closely related to the R. solanacearum species type strain, K60, but were isolated >50 years later. Four sequenced strains from Africa include a soil isolate from Nigeria (UW386, III-23), a tomato isolate from Senegal (UW763, I-14), and two potato isolates from the Madagascar highlands (RUN2474, III-19 and RUN2279, III-60). This resource will support studies of the genetic diversity, ecology, virulence, and microevolution of this globally distributed group of high-impact plant pathogens.
Imbalances in the gut microbiome are suspected as contributors to the pathogenesis of Systemic Lupus Erythematosus, and our studies and others have documented that patients with active Lupus nephritis have expansions of the obligate anaerobe, Ruminococcus blautia gnavus (RG). To investigate whether the RG strains in Lupus patients have in vivo pathogenic properties, we colonized C57BL/6 mice with individual RG strains from healthy adults or those from Lupus patients. These strains had a similar capacity for murine intestinal colonization, in antibiotic-preconditioned specific-pathogen-free, as well as germ-free adults, and their neonatally colonized litters. Lupus-derived RG strains induced high levels of intestinal permeability that was significantly greater in female than male mice, whereas the RG species-type strain (ATCC29149/VPI C7-1) from a healthy donor had little or no effects. Lupus RG strain-induced functional alterations were associated dysregulated occluden transcript production in the ileal wall as well as raised serum levels of zonulin, a regulator of tight junction formation between cells that form the gut barrier. Notably, the level of Lupus RG-induced intestinal permeability was significantly correlated with serum IgG anti RG cell-wall lipoglycan antibodies, and to anti-native DNA autoantibodies that are a biomarker for SLE. Strikingly, gut permeability was completely reversed by oral treatment with larazotide acetate, an octapeptide that is a specific molecular antagonist of zonulin. Taken together, these studies document a molecular pathway by which RG strains from Lupus patients induce a leaky gut and autoimmunity that have been implicated in the pathogenesis of flares of clinical Lupus disease.
Snow algae play crucial roles in cold ecosystems, however, many aspects related to their biology, adaptations and especially their diversity are not well known. To improve the identification of snow algae from colored snow, in the present study we used a polyphasic approach to describe a new Antarctic genus, Chlorominima with the species type Chlorominima collina. This new taxon was isolated of colored snow collected from the Collins Glacier (King George Island) in the Maritime Antarctic region. Microscopy revealed biflagellated ellipsoidal cells with a rounded posterior end, a C-shaped parietal chloroplast without a pyrenoid, eyespot, and discrete papillae. Several of these characteristics are typical of the genus Chloromonas, but the new isolate differs from the described species of this genus by the unusual small size of the cells, the presence of several vacuoles, the position of the nucleus and the shape of the chloroplast. Molecular analyzes confirm that the isolated alga does not belong to Chloromonas and therefore forms an independent lineage, which is closely related to other unidentified Antarctic and Arctic strains, forming a polar subclade in the Stephanosphaerinia phylogroup within the Chlamydomonadales. Secondary structure comparisons of the ITS2 rDNA marker support the idea that new strain is a distinct taxon within of Caudivolvoxa. Physiological experiments revealed psychrophilic characteristics, which are typical of true snow algae. This status was confirmed by the partial transcriptome obtained at 2°C, in which various cold-responsive and cryoprotective genes were identified. This study explores the systematics, cold acclimatization strategies and their implications for the Antarctic snow flora.
A catalog of the Brachystomatidae of Chile is provided. We present all valid names and synonyms for the 36 species and five genera distributed in the country, including information about name, author, year of publication, page number, type species, type depository, type locality and references. Heterophlebus Philippi is the richest genus in Chile, with 16 species, followed by Apalocnemis Philippi with 11 species, Ceratomerus Philippi with seven and Gondwanamyia Sinclair, Cumming, Brooks, Plant & Saigusa and Hyperperacera Collin with one species each. The geographical distribution of the different species was compiled from bibliographic data and revised collections.
In this article, we present a revised taxonomic circumscription of Aconitum subg. Aconitum (Ranunculaceae) in Europe. In total, the subgenus contains some 250 species with the major center of diversity in Eastern Asia. Altogether 94 taxa (species and infraspecific taxa, including hybrids) occur in Europe. Among them, 22 are native species, and 28 are nothospecies (including hybrid formulae). The research is based on former (since Linnaeus) and recent species diagnoses integrating herbarium and field studies carried out in the Alps, Carpathians, Balkans, Spanish Sierra Nevada, Sudetes, and Corsica. The subgenus includes three sections in Europe: the diploid sect. Cammarum, the tetraploid sect. Aconitum, and the monospecific, allopolyploid sect. Angustifolium. Additionally, a triploid, hybridogenous nothosection Acomarum (sect. Aconitum × sect. Cammarum) is presented. For each species, type citation, a concise morphological description, including infraspecific variation and hybridization, geographical distribution, and iconography sources are given. Also, a key to the determination of all taxa is presented. The proposed system scrutinizes former and recent species concepts and gives a base for further studies on the genus’ phylogeny and biotechnology.
AbstractSynaptic vesicles, which are endogenous to neurotransmitters, are involved in exocytosis by active potentials and release neurotransmitters. Synaptic vesicles used in neurotransmitter release are reused via endocytosis to maintain a pool of synaptic vesicles. Synaptic vesicles show different types of exo- and endocytosis depending on animal species, type of nerve cell, and electrical activity. To accurately understand the dynamics of synaptic vesicles, direct observation of synaptic vesicles is required; however, it was difficult to observe synaptic vesicles of size 40–50 nm in living neurons. The exo-and endocytosis of synaptic vesicles was confirmed by labeling the vesicles with a fluorescent agent and measuring the changes in fluorescence intensity. To date, various methods of labeling synaptic vesicles have been proposed, and each method has its own characteristics, strength, and drawbacks. In this study, we introduce methods that can measure presynaptic activity and describe the characteristics of each technique.
Coastal geomorphology deals with the various landforms and different processes involved in the development of coast. In the alluvium coast, biology plays a significant role as a coastal process. The present study aims at the role of vegetation in the geomorphic system, with the main consideration of flora. The study has been conducted in an alluvium coast along the Bay of Bengal adjacent to the sections of Balasore and Kanthi coastal plain. The geomorphological map and Normalized Difference Vegetation Index (NDVI) have been generated with the help of Landsat 5 TM, Landsat 8 OLI & SOI Toposheet with the help of Arc GIS & Erdas Imagine software. The ground truthing of relationships between geomorphological units & vegetation types are established with the help of GPS survey and counting of species type. The selected nine environmental transects of Balasore and Kanthi coastal plains i.e. Dagara, Kankadapal, Talsari, Udaipur, Digha, Shankarpur, Tajpur, Mandarmani & Junput have been considered for assessing the role of vegetation in sediment accretion and sediment surface stability. The study shows that the surface stability is achieved with dense vegetation covers and their types in Mangrove Swamp, Salt marsh and sand dunes whereas; the erosional area of geomorphic units has less vegetation cover and insignificant species type. The perfect relationship are found in the shore transect of Balasore-Kanthi coastal interface area (New Digha to Bichitrapur). Finally, it is also observed that the above area is less disturbed by human activities in compare to others.
A catalogue of the Pyrgotidae (Diptera) from Chile is provided. All valid names are presented, comprising three species in two genera for the country. All references known to us from the taxonomic and biological literature, to the included names, are provided, including information about name, author, year of publication, page number, type species, type locality, distribution, and references.