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981.
Mauro I. Schiaffini Magalí Gabrielli Francisco J. Prevosti Yamila P. Cardoso Diego Castillo Roberto Bo Emma Casanave Marta Lizarralde 《Zoological Journal of the Linnean Society》2013,167(2):327-344
Despite recent taxonomic evaluations of Mephitidae and North American hog‐nosed skunks, southern South American species of Conepatus have not been thoroughly examined in a systematic context. Conepatus chinga and Conepatus humboldtii were described more than 150 years ago, based on external characters such as hair coloration and size. Although historically recognized as valid species, to date no detailed systematic analysis has been performed for either of these taxa. Herein, we evaluated the taxonomic status of C. chinga and C. humboldtii within the southern part of South America using geometric morphometrics of the skull and mandible, mitochondrial DNA analysis using the cytochrome b and cytochrome oxidase c subunit I genes, and also control region and pelage pattern variation. We failed to find morphological (skull shape and pelage coloration patterns) or molecular differences between these two species; thus, we considered that the specimens assigned to C. chinga and C. humboldtii belong to the same species. Our results indicate that environmental variation seems to be responsible for shape and size variation in Conepatus skulls from southern South America. © 2013 The Linnean Society of London 相似文献
982.
Revision of the section Anillochlamys Jeannel, 1909 (Coleoptera: Leiodidae: Cholevinae: Leptodirini)
José Ma Salgado 《法国昆虫学会纪事》2013,49(4):361-384
The taxonomy of the Iberian Leptodirini species of the section Anillochlamys Jeannel, 1909 has been revised. The proposed classification is based on the study of the genital structures of both sexes, in particular the internal sac of the aedeagus. According to the different models of internal sacs, the following genera, species and subspecies are identified: genus Anillochlamys Jeannel, 1909: A. aurouxi Español, 1965, A. bueni Jeannel, 1909 (= A. avariae Comas, 1977 n.syn.), A. cullelli Lagar, 1978, A. moroderi Bolívar, 1923 (= A. negrei Comas, 1990 n. syn.), A. subtruncatus Jeannel, 1930 (= A. baguenai Jeannel, 1930) and A. tropicus (Abeille, 1881) (= Adelops hispanicus Ehlers, 1893; A. tropicus var. apicalis Jeannel, 1909); genus Paranillochlamys Zariquiey, 1940: P. catalonicus (Jeannel, 1913), P. urgellesi (Español, 1965) and P. velox Zariquiey, 1940 (= P. velox montadai Lagar, 1963 n. syn.); genus Pseudochlamys Comas, 1977: P. raholai (Zariquiey, 1922) (= Anillochlamys raholai luis-bofilli Zariquiey, 1940 n. syn.); genus Spelaeochlamys Dieck, 1870 (= Typhlochlamys Español, 1975 n.syn.): S.bardisai (Español, 1975) (= Typhlochlamys escolai Comas, 1978 n. syn.), S. ehlersi Dieck, 1870 and S. ehlersi verai Comas, 1977 n. stat. 相似文献
983.
André Nel 《法国昆虫学会纪事》2013,49(1):23-29
A new deposit of Lower Cretaceous amber, found in Charente-Maritime (SW France) has yielded an important entomofauna with numerous arthropod associations characteristic of moist ground. We describe a new species of Dolichopodidae: ‘Microphorinae’(Diptera: Empidoidea), Microphorites deploegi n. sp. on the basis of seven male and female specimens of exceptional state of preservation. This genus was previously only known from Lebanese amber of the Lower Cretaceous. The present discovery supports a reconstruction of the palaeoenvironment as a sandy beach along the sea, under a warm climate. 相似文献
984.
The first fossil representative of the jewel damselflies (Calopterygoidea: Chlorocyphidae), a family of large, prominent, and often brilliantly colored Old World tropical Zygoptera, is described and figured. Chlorocypha cordasevae n. sp. was recovered from the Late Miocene (Early Pannonian, Serravalian to Tortonian, c.11 Ma) locality of Paldau, in the Styrian Basin, Austria. The fossil seems to be related to the African genus Chlorocypha Fraser, and within a larger group of African genera also including Stenocypha Dijkstra, Africocypha Pinhey, and Platycypha Fraser, and collectively set apart from southern Asiatic genera. The discovery of a central European species of Chlorocypha as recently as the Late Miocene reveals a much wider range to the family than its generally disjunctive modern distribution, demonstrating a Neogene contraction to their range, likely in connection with climatic cooling, drying, and developing seasonality. Modern chlorocyphids live under warm, humid climates, and the presence of C. cordasevae in the Pannonian fauna of Paldau further corroborates such a subtropical paleoclimate for the locality at that time. 相似文献
985.
Until now, two species of Borgatomelissa Patiny, 2000 have been described, both from loci typici located in the Near East and eastern Africa. Borgatomelissa brevipennis (Walker, 1871), the most widespread taxon, has also been found in the southern Sahelo-Sudanian belt of the Sahara. A third species from eastern Morocco is described in the present study: Borgatomelissa flavimaura n. sp. In addition to taxonomic insights, the new species sheds a new light on the biogeography of the genus. 相似文献
986.
Sebastian Peter Matthias Kinne René Ullrich Gernot Kayser Martin Hofrichter 《Enzyme and microbial technology》2013,52(6-7):370-376
Unspecific peroxygenases (EC 1.11.2.1) represent a group of secreted heme-thiolate proteins that are capable of catalyzing the mono-oxygenation of diverse organic compounds, using only H2O2 as a co-substrate. Here we show that the peroxygenase secreted by the fungus Agrocybe aegerita catalyzed the oxidation of 20 different alkenes. Five branched alkenes, among them 2,3-dimethyl-2-butene and cis-2-butene, as well as propene and butadiene were epoxidized with complete regioselectivity. Longer linear alkenes with a terminal double bond (e.g. 1-octene) and cyclic alkenes (e.g. cyclohexene) were converted into the corresponding epoxides and allylic hydroxylation products; oxidation of the cyclic monoterpene limonene yielded three oxygenation products (two epoxides and an alcohol). In the case of 1-alkenes, the conversion occurred with moderate stereoselectivity, in which the preponderance for the (S)-enantiomer reached up to 72% ee for the epoxide product. The apparent Michaelis–Menten constant (Km) for the epoxidation of the model substrate 2-methyl-2-butene was 5 mM, the turnover number (kcat) 1.3 × 103 s?1 and the calculated catalytic efficiency, kcat/Km, was 2.5 × 105 M?1 s?1. As epoxides represent chemical building blocks of high relevance, new enzymatic epoxidation pathways are of interest to complement existing chemical and biotechnological approaches. Stable and versatile peroxygenases as that of A. aegerita may form a promising biocatalytic platform for the development of such enzyme-based syntheses. 相似文献
987.
Gonzalo Castillo‐Campos José G. García‐Franco María Luisa Martínez 《Nordic Journal of Botany》2013,31(4):449-452
Spathacanthus magdalenae Cast.‐Campos (Acanthaceae) is described and illustrated as a new riparian forest species from central Veracruz and from the eastern slopes of the volcano Cofre de Perote, Mexico. The new species is similar to Spathacanthus parviflorus, but differs in wider leaves and longer corolla tube. A key to all four species of Spathacanthus is provided. 相似文献
988.
989.
Nabila Haddad Margarida Saramago Rute?G. Matos Hervé Prévost Cecília?M. Arraiano 《Bioscience reports》2013,33(6)
Campylobacter jejuni is a foodborne bacterial pathogen, which is now considered as a leading cause of human bacterial gastroenteritis. The information regarding ribonucleases in C. jejuni is very scarce but there are hints that they can be instrumental in virulence mechanisms. Namely, PNPase (polynucleotide phosphorylase) was shown to allow survival of C. jejuni in refrigerated conditions, to facilitate bacterial swimming, cell adhesion, colonization and invasion. In several microorganisms PNPase synthesis is auto-controlled in an RNase III (ribonuclease III)-dependent mechanism. Thereby, we have cloned, overexpressed, purified and characterized Cj-RNase III (C. jejuni RNase III). We have demonstrated that Cj-RNase III is able to complement an Escherichia coli rnc-deficient strain in 30S rRNA processing and PNPase regulation. Cj-RNase III was shown to be active in an unexpectedly large range of conditions, and Mn2+ seems to be its preferred co-factor, contrarily to what was described for other RNase III orthologues. The results lead us to speculate that Cj-RNase III may have an important role under a Mn2+-rich environment. Mutational analysis strengthened the function of some residues in the catalytic mechanism of action of RNase III, which was shown to be conserved. 相似文献
990.
Michel Ronjat José Pablo Finkelstein Paola Llanos Luis Montecinos Hicham Bichraoui Michel De Waard Cecilia Hidalgo Ricardo Bull 《Cell calcium》2013,53(5-6):357-365
The scorpion toxin maurocalcine acts as a high affinity agonist of the type-1 ryanodine receptor expressed in skeletal muscle. Here, we investigated the effects of the reducing agent dithiothreitol or the oxidizing reagent thimerosal on type-1 ryanodine receptor stimulation by maurocalcine. Maurocalcine addition to sarcoplasmic reticulum vesicles actively loaded with calcium elicited Ca2+ release from native vesicles and from vesicles pre-incubated with dithiothreitol; thimerosal addition to native vesicles after Ca2+ uptake completion prevented this response. Maurocalcine enhanced equilibrium [3H]-ryanodine binding to native and to dithiothreitol-treated reticulum vesicles, and increased 5-fold the apparent Ki for Mg2+ inhibition of [3H]-ryanodine binding to native vesicles. Single calcium release channels incorporated in planar lipid bilayers displayed a long-lived open sub-conductance state after maurocalcine addition. The fractional time spent in this sub-conductance state decreased when lowering cytoplasmic [Ca2+] from 10 μM to 0.1 μM or at cytoplasmic [Mg2+] ≥ 30 μM. At 0.1 μM [Ca2+], only channels that displayed poor activation by Ca2+ were readily activated by 5 nM maurocalcine; subsequent incubation with thimerosal abolished the sub-conductance state induced by maurocalcine. We interpret these results as an indication that maurocalcine acts as a more effective type-1 ryanodine receptor channel agonist under reducing conditions. 相似文献