Two new species of <Emphasis Type="Italic">Conidiobolus</Emphasis> occurring in Anhui,China

Two new species of Conidiobolus were isolated from Anhui Province, China. A polyphasic taxonomic approach comprising morphological characteristics and molecular data (the nuclear large subunit of ribosomal DNA and the translation elongation factor 1 alpha gene sequences) was applied to determine their novel taxonomic status in the genus Conidiobolus. The new species C. mirabilis is a sister group to C. thromoides, but morphologically differs by smaller primary conidia and a unique formation of zygospores among two to four adjacent hyphal segments. The other new species C. pachyzygosporus characterized with thick-walled zygospores is phylogenetically closely related to C. antarcticus, C. couchii, and C. osmodes.     

New evidence of nearshore Mid-Triassic <Emphasis Type="Italic">Zoophycos</Emphasis>: morphological and paleoenvironmental characterization

Zoophycos is a well-known trace fossil common throughout the Phanerozoic. Paleozoic forms show important differences in morphology and habitat distribution with respect to the Jurassic, Cretaceous, and Cenozoic ones. Therefore, Early–Middle Triassic is considered a crucial time-span for the understanding of the evolution of this trace fossil. So far, Early Triassic Zoophycos is unknown and Middle Triassic forms were recorded only in deposits from Thuringia. The morphology and paleoenvironment of Zoophycos from the middle–upper Muschelkalk of the Iberian Range is herein described. The best-preserved trace fossils occur in a dolomicritic bed Ladinian in age, and are represented by small forms with a subcircular, slightly lobed outline and very little penetration depth. They were deposited in a very shallow, quiet-water environment with transition to supratidal/emerged areas. The low diversity of both trace fossils and skeletal remains point to stressful conditions related to strong salinity variations and/or poor water circulation. A comparison was made with Zoophycos from Anisian deposits of the Muschelkalk in Germany. This showed that both forms are quite simple and penetrate only the shallowest tiers, although they are different in whorl outline and lobe shape. This confirms that, notwithstanding the morphological variability of this group, Zoophycos still maintained a quite simple structure in the Triassic. A shallow-water environment was deduced for both localities, confirming that at least until the Early Jurassic Zoophycos had not definitively migrated toward deep-water areas.     

<Emphasis Type="Italic">Candida krusei</Emphasis> and <Emphasis Type="Italic">Candida glabrata</Emphasis> reduce the filamentation of <Emphasis Type="Italic">Candida albicans</Emphasis> by downregulating expression of <Emphasis Type="Italic">HWP1</Emphasis> gene

Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene.     

Influence of cold on organization of actin filaments of different types of root cells in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

The effect of the low temperature (+4°C) on the organization of actin filaments (microfilaments) of cells from different growth zones has been studied in the roots of Arabidopsis thaliana (L.). It was found that cold treatment inhibited the growth of the primary root and changed its morphology, causing a formation of large number of deformed (ectopic) root hairs in differentiation zone. The temporal relationship between the disorientation and the organization of actin filaments and the detected changes of growth and morphology of roots after cold treatment was shown. It has been found that actin filaments of root hairs, meristematic cells, cells of elongation zone, and epidermal cells of all root zones of A. thaliana are the most sensitive to the cold.     

The NADPH oxidase AoNoxA in <Emphasis Type="Italic">Arthrobotrys oligospora</Emphasis> functions as an initial factor in the infection of <Emphasis Type="Italic">Caenorhabditis elegans</Emphasis>

Reactive oxygen species (ROS) produced by NADPH oxidases can serve as signaling molecules to regulate a variety of physiological processes in multi-cellular organisms. In the nematophagous fungus Arthrobotrys oligospora, we found that ROS were produced during conidial germination, hyphal extension, and trap formation in the presence of nematodes. Generation of an AoNoxA knockout strain demonstrated the crucial role of NADPH oxidase in the production of ROS in A. oligospora, with trap formation impaired in the AoNoxA mutant, even in the presence of the nematode host. In addition, the expression of virulence factor serine protease P186 was up-regulated in the wild-type strain, but not in the mutant strain, in the presence of Caenorhabditis elegans. These results indicate that ROS derived from AoNoxA are essential for full virulence of A. oligospora in nematodes.     

<Emphasis Type="Italic">Cannabis</Emphasis> is indigenous to Europe and cultivation began during the Copper or Bronze age: a probabilistic synthesis of fossil pollen studies

Conventional wisdom states Cannabis sativa originated in Asia and its dispersal to Europe depended upon human transport. Various Neolithic or Bronze age groups have been named as pioneer cultivators. These theses were tested by examining fossil pollen studies (FPSs), obtained from the European Pollen Database. Many FPSs report Cannabis or Humulus (C/H) with collective names (e.g. Cannabis/Humulus or Cannabaceae). To dissect these aggregate data, we used ecological proxies to differentiate C/H pollen, as follows: unknown C/H pollen that appeared in a pollen assemblage suggestive of steppe (Poaceae, Artemisia, Chenopodiaceae) we interpreted as wild-type Cannabis. C/H pollen in a mesophytic forest assemblage (Alnus, Salix, Populus) we interpreted as Humulus. C/H pollen curves that upsurged and appeared de novo alongside crop pollen grains we interpreted as cultivated hemp. FPSs were mapped and compared to the territories of archaeological cultures. We analysed 479 FPSs from the Holocene/Late Glacial, plus 36 FPSs from older strata. The results showed C/H pollen consistent with wild-type C. sativa in steppe and dry tundra landscapes throughout Europe during the early Holocene, Late Glacial, and previous glaciations. During the warm and wet Holocene Climactic Optimum, forests replaced steppe, and Humulus dominated. Cannabis retreated to steppe refugia. C/H pollen consistent with cultivated hemp first appeared in the Pontic-Caspian steppe refugium. GIS mapping linked cultivation with the Copper age Varna/Gumelni?a culture, and the Bronze age Yamnaya and Terramara cultures. An Iron age steppe culture, the Scythians, likely introduced hemp cultivation to Celtic and Proto-Slavic cultures.     

Morphological and Taxonomic Interpretation of <Emphasis Type="Italic">Orestovia</Emphasis> and <Emphasis Type="Italic">Schuguria</Emphasis>, Enigmatic Devonian Plants from Russia

A detailed study of the external and internal surfaces of the cuticle of Orestovia and Schuguria using scanning electron microscopy and confocal laser microscopy has shown that the structures formerly interpreted as stomata or reproductive organs are most likely to be gland cells producing mucilage. Each structure represents a single large cell with a complex aperture on the external wall. In addition, a reproductive organ similar to multilocular sporangia known in brown algae of the order Ectocarpales has been found in attachment to a compression fossil of Orestovia. These data suggest similarity of the genera studied with brown algae.     

A description of the larvae of <Emphasis Type="Italic">Cinygmula unicolorata</Emphasis> Tshernova, 1979 and <Emphasis Type="Italic">Cinygmula malaisei</Emphasis> (Ulmer, 1927) (Ephemeroptera,Heptageniidae) from the Russian Far East

The larvae of Cinygmula malaisei (Ulmer, 1927) and Cinygmula unicolorata Tshernova, 1979 from the Russian Far East are described and illustrated. The larva of Cinygmula unicolorata is similar to those of Cinygmula putoranica Kluge, 1980 and Cinygmula uyka Gorovaya et Tiunova, 2013 but differs from the larva of C. uyka in the absence of gill filaments and from that of C. unicolorata in the shape of the first gill (tergalia). The upper outer margin of the first gill is rounded in the larva of C. unicolorata and almost straight in C. putoranica; the gills of C. unicolorata are matte and the trachea is poorly expressed, in contrast to the distinctly brown trachea of C. putoranica. The larvae of Cinygmula malaisei are similar to those of C. irina and C. autumnalis but differ from the latter in the presence of gill filaments. The larva of C. malaise differs from that of C. irina in the rounded outer margin of the first gill, the shape of gills VI and VII, and in the size of the leg segments.     

A Middle Pleistocene Sea Otter from Northern California and the Antiquity of <Emphasis Type="Italic">Enhydra</Emphasis> in the Pacific Basin

Extant sea otters (Enhydra lutris) are remarkably well understood in terms of behavior, ecology, and interactions with humans, but the evolutionary history of this charismatic marine mammal is limited owing to a fragmentary fossil record. Disagreements over the generic assignment of various fossil otter remains to members of the tribe Enhydrini, and limited geochronologic data for these records have impeded attempts to interpret the evolutionary biogeography of Enhydra. A well-preserved femur of Enhydra sp. from a middle Pleistocene horizon within the Merced Formation of northern California is the oldest record of Enhydra in the Pacific with robust geochronologic age control. Bracketing ⁸⁷Sr/⁸⁶Sr dates indicate an age of 620–670 ka. Reappraisal of the geochronologic age of various occurrences of Enhydrini indicate dispersal of Enhydra into the Pacific through the Bering Strait no earlier than the middle Pleistocene. Somewhat older early Pleistocene fossils of Enhydra from Alaska and England suggest an Arctic or North Atlantic origin of the Enhydra lineage.     

The antibacterial agent,moxifloxacin inhibits virulence factors of <Emphasis Type="Italic">Candida albicans</Emphasis> through multitargeting

Fluoroquinolines are broad spectrum fourth generation antibiotics. Some of the Fluoroquinolines exhibit antifungal activity. We are reporting the potential mechanism of action of a fluoroquinoline antibiotic, moxifloxacin on the growth, morphogenesis and biofilm formation of the human pathogen Candida albicans. Moxifloxacin was found to be Candidacidal in nature. Moxifloxacin seems to inhibit the yeast to Hyphal morphogenesis by affecting signaling pathways. It arrested the cell cycle of C. albicans at S phase. Docking of moxifloxacin with predicted structure of C. albicans DNA Topoisomerase II suggests that moxifloxacin may bind and inhibit the activity of DNA Topoisomerase II in C. albicans. Moxifloxacin could be used as a dual purpose antibiotic for treating mixed infections caused by bacteria as well as C. albicans. In addition chances of developing moxifloxacin resistance in C. albicans are less considering the fact that moxifloxacin may target multiple steps in yeast to hyphal transition in C. albicans.     

Unique configuration of genes of silicon transporter in the freshwater pennate diatom <Emphasis Type="Italic">Synedra acus</Emphasis> subsp. <Emphasis Type="Italic">radians</Emphasis>

The existence of the cluster of duplicated sit silicon transporter genes in the chromosome of the diatom Synedra acus subsp. radians was shown for the first time. Earlier, the localization of sit genes in the same chromosome and cluster formation caused by gene duplication was shown only for the marine raphid pennate diatom P. tricornutum. Only non-clustered sit genes were found in the genomes of other diatoms. It is reasonable to assume that sit tandem (sit-td) and sit triplet (sit-tri) genes of S. acus subsp. radians occurred as a result of gene duplication followed by divergence of gene copies.     

The first Eocene tumbling beetle of the genus <Emphasis Type="Italic">Isotrilophus</Emphasis> (Insecta: Coleoptera: Mordellidae) from the Green River Formation (Colorado,United States)

The first fossil representative of the genus Isotrilophus Liljeblad (Mordellidae), I. rasnitsyni sp. nov., from the Lower Eocene of the Green River Formation (Colorado) is described. The new species differs from its only congener, I. erraticus (Smith, 1883), in the shape of eye, metepisternum, configuration of temporal angle, lateral edge of the prothorax, and in the length ratio of the prothorax and elytra. The first I. erraticus south of Nicaragua (e.g., in Costa Rica and Peru) are recorded.     

Genetic Collection of Meiotic Mutants of Rye <Emphasis Type="Italic">Secale cereale</Emphasis> L.

Genetic collection of meiotic mutants of winter rye Secale cereale L. (2n = 14) was created. Mutations were detected in inbred F₂ generations after self-fertilization of the F₁ hybrids, obtained by individual crossing of rye plants (cultivar Vyatka) or weedy rye with plants from autofertile lines. The mutations cause partial or complete plant sterility and are maintained in collection in a heterozygous state. Genetic analysis accompanied by cytogenetic study of meiosis has revealed six mutation types. (1) Nonallelic asynaptic mutations sy1 and sy9 caused the formation of only axial chromosome elements in prophase and anaphase. The synaptonemal complexes (SCs) were absent, the formation of the chromosome “bouquet” was impaired, and all chromosomes were univalent in meiotic metaphase I in 96.8% (sy1) and 67% (sy2) of cells. (2) Weak asynaptic mutation sy3, which hindered complete termination of synapsis in prophase I. Subterminal asynaptic segments were always observed in the SC, and at least one pair of univalents was present in metaphase I, but the number of cells with 14 univalents did not exceed 2%. (3) Mutations sy2, sy6, sy7, sy8, sy10, and sy19, which caused partially nonhomologous synapsis: change in pairing partners and fold-back chromosome synapsis in prophase I. In metaphase I, the number of univalents varied and multivalents were observed. (4) Mutation mei6, which causes the formation of ultrastructural protrusions on the lateral SC elements, gaps and branching of these elements. (5) Allelic mutations mei8 and mei8-10, which caused irregular chromatin condensation along chromosomes in prophase I, sticking and fragmentation of chromosomes in metaphase I. (6) Allelic mutations mei5 and mei10, which caused chromosome hypercondensation, defects of the division spindle formation, and random arrest of cells at different meiotic stages. However, these mutations did not affect the formation of microspore envelopes even around the cells, whose development was blocked at prophase I. Analysis of cytological pictures of meiosis in double rye mutants reveled epistatic interaction in the mutation series sy9 > sy1 > sy3 > sy19, which reflects the order of switching these genes in the course of meiosis. The expression of genes sy2 and sy19 was shown to be controlled by modifier genes. Most meiotic mutations found in rye have analogs in other plant species.     

New paleobiogeographical and paleoenvironmental insight through the Tortonian brachiopod and ichnofauna assemblages from the Mediterranean-Atlantic seaway (Guadix Basin,SE Spain)

The paleogeography of the Late Neogene Atlantic-Mediterranean seaway via the Betic-Rifean Domain is quite complex due to the presence of several marine corridors. The study of transitional basins in these seaways is crucial to understand the configuration and evolution of the Mediterranean-Atlantic inter-connection. A mixed skeletal-siliciclastic sandstone succession located in one of these transitional areas (Guadix Basin, Southern Spain) was studied from a comprehensive paleontological standpoint focused on the main benthic assemblages (foraminifera, brachiopods, and trace fossils), integrating the data with the study of planktic foraminifera for an accurate biostratigraphic framework. Brachiopods are mostly represented by the Aphelesia-Gryphus assemblage. Two trace fossil assemblages were observed, dominated by Ophiomorpha with Bichordites (1) and Macaronichnus (2), respectively. The benthic foraminiferal assemblage is mostly represented by Planulina and Cibicides. The data gathered from the benthic communities reveal habitats with high-energy and turbulent conditions in an outer neritic-upper bathyal bathymetric range. Brachiopods from the Alicún section show a Mediterranean paleobiogeographic affinity. They were constrained in the Late Tortonian to the restricted basins of the Betic-Rifean Seaway and after the Messinian Salinity Crisis proliferated in both Mediterranean- and Atlantic-type basins of the Betic-Rifean Domain. The Guadix Basin contributed to the Mediterranean-Atlantic faunal inter-connection through the Betic-Rifean Seaway during the Late Tortonian and facilitated the earliest Pliocene expansion of brachiopods in the Mediterranean.     

Physiological and Morphological Characteristics of Acidophilic Bacteria <Emphasis Type="Italic">Leptospirillum ferriphilum</Emphasis> and <Emphasis Type="Italic">Acidithiobacillus thiooxidans</Emphasis>, Members of a Chemolithotrophic Microbial Consortium

A thermoacidophilic consortium of chemolithotrophic microorganisms oxidizing the concentrate of high-pyrrhotite pyrite?arsenopyrite ore at 38–40°C was isolated. The most active members of the consortium were identified as Leptospirillum ferriphilum, Acidithiobacillus thiooxidans, Ferroplasma acidiphilum, and Sulfobacillus thermotolerans. Leptospirillum and Thiobacillus species were the most numerous members of the consortium and had the highest activity of ferrous iron and sulfur oxidation, respectively. The optimal temperature values for the growth of both isolates were within 35–38°C. The optimal ranges of initial pH were 1.0–1.2 and 1.75–1.85 for leptospirilla and 1.7–3.3 for thiobacilli with the pH optimum of 1.9. Significant polymorphism and specific cyclic growth with formation of vibrios, spirilla, rods with different end shape, spiral filaments, numerous “pseudococci,” and densely packed spiral filaments surrounded by a sheath were revealed for the Leptospirillum isolate. Two latter morphoforms of L. ferriphilum were not previously described. Differences in ability of the morphoforms to oxidize Fe²⁺ were revealed. For the first time, the possibility of growth in the presence of organic substances was demonstrated for A. thiooxidans. The rates of growth and substrate oxidation, cell size, and the maximal cell yield decreased insignificantly in comparison with the lithoautotrophic strain.     

Molecular phylogenetics and anti-<Emphasis Type="Italic">Pythium</Emphasis> activity of endophytes from rhizomes of wild ginger congener, <Emphasis Type="Italic">Zingiber zerumbet</Emphasis> Smith

Zingiber zerumbet, a perennial rhizomatous herb exhibits remarkable disease resistance as well as a wide range of pharmacological activities. Towards characterizing the endophytic population of Z. zerumbet rhizomes, experiments were carried out during two different growing seasons viz., early-June of 2013 and late-July of 2014. A total of 34 endophytes were isolated and categorized into 11 morphologically distinct groups. Fungi were observed to predominate bacterial species with colonization frequency values ranging from 12.5 to 50 %. Among the 11 endophyte groups isolated, molecular analyses based on ITS/16S rRNA gene sequences identified seven isolate groups as Fusarium solani, two as F. oxysporum and one as the bacterium Rhizobium spp. Phylogenetic tree clustered the ITS sequences from Z. zerumbet endophytes into distinct clades consistent with morphological and sequence analysis. Dual culture assays were carried out to determine antagonistic activity of the isolated endophytes against Pythium myriotylum, an economically significant soil-borne phytopathogen of cultivated ginger. Experiments revealed significant P. myriotylum growth inhibition by F. solani and F. oxysporum isolates with percentage of inhibition (PoI) ranging from 45.17 ± 0.29 to 62.2 ± 2.58 with F. oxysporum exhibiting higher PoI values against P. myriotylum. Using ZzEF8 metabolite extract, concentration-dependent P. myriotylum hyphal growth inhibition was observed following radial diffusion assays. These observations were confirmed by scanning electron microscopy analysis wherein exposure to ZzEF8 metabolite extract induced hyphal deformities. Results indicate Z. zerumbet endophytes as promising resources for biologically active compounds and as biocontrol agents for soft rot disease management caused by Pythium spp.