Trace Fossils from the Brioverian (Ediacaran–Fortunian) in Brittany (NW France)

The Ediacaran–Fortunian ichnofauna from Central Brittany (NW France) is revised for the first time since the pioneering work by Lebesconte at the end of the 19th century. The study is based on fossils from the type-localities of the historical Brioverian taxa Montfortia (traces from Montfort-sur-Meu) and Neantia (wrinkle surfaces from Néant-sur-Yvel), and on two new outcrops from Saint-Gonlay. The ichnofossil assemblage includes Helminthoidichnites tenuis, Helminthopsis tenuis, Gordia marina, Palaeophycus tubularis, ?Neonereites uniserialis, and ?Spirodesmos archimedeus. Locally, the grazing traces are associated with wrinkle surfaces considered as microbially induced sedimentary structures (MISS). The sedimentological characteristics of these deposits correspond to a shelf marine environment. Both U-Pb datings on detrital zircon and ichnostratigraphic criteria tend toward an Ediacaran age of the fossiliferous deposits, but we cannot exclude the possibility of a Fortunian age at the present state of knowledge.     

Anion inhibition study of the β-carbonic anhydrase (CahB1) from the cyanobacterium Coleofasciculus chthonoplastes (ex-Microcoleus chthonoplastes)

We investigated the catalytic activity and inhibition of the β-class carbonic anhydrase (CA, EC 4.2.1.1) CahB1, from the relict cyanobacterium Coleofasciculus chthonoplastes (previously denominated Microcoleus chthonoplastes). The enzyme showed good activity as a catalyst for the CO₂ hydration, with a k_cat of 2.4 × 10⁵ s⁻¹ and a k_cat/K_m of 6.3 × 10⁷ M⁻¹ s⁻¹. A range of inorganic anions and small molecules were investigated as inhibitors of CahB1. Perchlorate and tetrafluoroborate did not inhibit the enzyme (K_Is >200 mM) whereas selenate and selenocyanide were ineffective inhibitors too, with K_Is of 29.9–48.61 mM. The halides, pseudohalides, carbonate, bicarbonate, trithiocarbonate and a range of heavy metal ions-containing anions were submillimolar–millimolar inhibitors (K_Is in the range of 0.15–0.90 mM). The best CahB1 inhibitors were N,N-diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid and phenylarsonic acid, with K_Is in the range of 8–75 μM, whereas acetazolamide inhibited the enzyme with a K_I of 76 nM. This is the first kinetic and inhibition study of a cyanobacterial CA. As these enzymes are widespread in many cyanobacteria, being crucial for the carbon concentrating mechanism which assures substrate to RubisCO for the CO₂ fixation by these organisms, a detailed kinetic/inhibition study may be essential for a better understanding of this superfamily of metalloenzymes and for potential biotechnological applications in biomimetic CO₂ capture processes.     

Properties of the β-d-glucosidase (cellobiase) from the wood-rotting fungus,Coriolus versicolor

Summary Structural and kinetic parameters of the -d-glucosidase (cellobiase, -d-glucoside glucohydrolase) from Coriolus versicolor have been determined. It is a high molecular weight glycoprotein (300,000 d) composed 10% by weight of protein, 90% by weight of carbohydrate in which glucose is the primary hexose sugar. The K_m for 4-nitrophenyl--d-glucopyranoside (4 NPG) and cellobiose are 0.276 and 2.94 mM respectively at pH 4.5 and 40°. d-Glucose is a competitive inhibitor with a K_i of 1.8 mM with 4 NPG as substrate, and at high concentrations, cellobiose exhibits a substrate inhibition effect on the enzyme, so negating attempts to overcome the competitive inhibition of glucose by increasing the concentration of the substrate.     

A traversodont cynodont from the Middle Triassic (Ladinian) of Baden-Württemberg (Germany)

Nanogomphodon wildi n. gen., n. sp. is based on a tiny lower postcanine tooth from the lower Lettenkeuper (Lower Keuper or Erfurt Formation; Ladinian) of Michelbach an der Bilz (Baden-Württemberg). It represents the first record of a traversodont cynodont from the Middle Triassic of Europe and exhibits a distinctive combination of dental features. Along with recent discoveries of other traversodont taxa from the Upper Triassic of eastern North America,Nanogomphodon indicates the existence of a distinct lineage of these cynodonts in the Northern Hemisphere.      

Diversity of actinomycetes isolated from Challenger Deep sediment (10,898 m) from the Mariana Trench

Thirty-eight actinomycetes were isolated from sediment collected from the Mariana Trench (10,898 m) using marine agar and media selective for actinomycetes, notably raffinose-histidine agar. The isolates were assigned to the class Actinobacteria using primers specific for members of this taxon. The phylogenetic analysis based on 16S rRNA gene sequencing showed that the isolates belonged to the genera Dermacoccus, Kocuria, Micromonospora, Streptomyces, Tsukamurella and Williamsia. All of the isolates were screened for genes encoding nonribosomal peptide and polyketide synthetases. Nonribosomal peptide synthetase sequences were detected in more than half of the isolates and polyketide synthases type I (PKS-I) were identified in five out of 38 strains. The Streptomyces isolates produced several unusual secondary metabolites, including a PKS-I associated product. In initial testing for piezotolerance, the Dermacoccus strain MT1.1 grew at elevated hydrostatic pressures.     

Bacterial communities in the 'petola' microbial mat from the Sečovlje salterns (Slovenia)

The Se?ovlje saltern is one of the few remaining solar salterns for traditional, seasonal salt production. The bottom of the crystallizer ponds is covered with a microbial mat, known as the 'petola', that has continuously been cultivated from medieval times. Outside the salt production season, the petola is fertilized with anoxic marine mud and covered with saline water; during the season, it is covered by brine. Here, we have applied culture-independent techniques and microelectrode-based activity measurements to study the bacterial communities in three different layers of the petola during the peak of the harvesting season. For reference, we used nonactive petola that had been abandoned for several years. The upper 2 mm of the petola were dominated by the cyanobacterial species Coleofasciculus chthonoplastes and the Phormidium/Lyngbya group, and Gammaproteobacteria (Acinetobacter sp.), while the third anoxic layer was dominated by as yet uncultured phyla. The nonactive petola showed a higher biodiversity. Oxygen and sulfide concentrations differed between the mats studied, in terms of the depth of oxygen penetration and diel changes. This study provides the first molecular insight into the microbiology of the petola, and it represents an important contribution towards understanding the geomicrobiological cycles of the traditional Se?ovlje saltern.     

Seasonal Rotifer Dynamics in the Long-term (1969–2002) Record from Lake Kinneret (Israel)

Long-term (1969–2002) data record of biomass distribution of rotifers in Lake Kinneret is combined with previously published information on their metabolic activity and newly calculated population dynamics parameters to synthesize a model of their seasonal dynamics in Lake Kinneret. Nineteen rotifer species were recorded in routine samples collected in Lake Kinneret (Israel) in 7 offshore (deeper than 5 m), stations, at 12 discrete depths during 1969–2002. Organisms were sorted and counted (including external egg carrying females), biomass was measured and calculated for the entire lake stock (g_w.w m⁻²; mg l⁻¹). Rates of grazing, respiration and production were measured experimentally at three different temperature ranges. Results were extrapolated to the lake community for months with similar temperatures. Rotifera comprised 7% of total zooplankton biomass in Lake Kinneret whilst Cladocera and Copepoda 58 and 35% respectively. Rotifers were found to be more abundant during December–June and decline in summer months. Monthly (1969–2001) means indicated total grazing capacity of rotifers as 11%, respiration as 9% and production as 3.7% of the total zooplankton metabolic activity. Positive relations were indicated between rotifer and small bodied cladoceran numerical concentrations. Population growth models suggest that rotifers are not food limited in Lake Kinneret but that fish predation plays an important role in regulating abundance in spring-summer and fall.     

GDP-Capture Compound — A novel tool for the profiling of GTPases in pro- and eukaryotes by capture compound mass spectrometry (CCMS)

The functional isolation of proteome subsets based on small molecule–protein interactions is an increasingly popular and promising field in functional proteomics. Entire protein families may be profiled on the basis of their common interaction with a metabolite or small molecule inhibitor. This is enabled by novel multifunctional small molecule probes. One platform approach in this field are Capture Compounds that contain a small molecule of interest to bind target proteins, a photo-activatable reactivity function to covalently trap bound proteins, and a sorting function to isolate Capture Compound–protein conjugates from complex biological samples for direct trypsinisation and protein identification by liquid chromatography/mass spectrometry (CCMS). We here present the synthesis and application of a novel GDP-Capture Compound for the functional enrichment of GTPases, a pivotal protein family that exerts key functions in signal transduction. We present data from CCMS experiments on two biological lysates from Escherichia coli and from human-derived Hek293 cells. The GDP-Capture Compound robustly captures a wide range of different GTPases from both systems and will be a valuable tool for the proteomic profiling of this important protein family.     

First record of ponyfishes (Perciformes: Leiognathidae) from the Oligocene of the Grube Unterfeld (“Frauenweiler”) clay pit

The first and presently only record of a ponyfish is described from the Lower Oligocene of the Grube Unterfeld (“Frauenweiler”) clay pit at Rauenberg (S Germany) and compared with other extant and fossil representatives of the Leiognathidae. It differs from all extant (and probably also fossil) members of this family in the coalescence of the ascending and articular processes of the premaxilla and the presence of a straight maxilla with a prominent dorsal crest. It furthermore differs from most extant and probably also fossil Leiognathidae in the combination of the following characters: the presence of multiple-rowed villiform teeth on the oral jaws; the presence of three supraneurals; third and fourth dorsal as well as third anal fin spines that are smooth at their anterior margins; delicate longitudinal surface striations on the neural and haemal spines of the vertebral column as well as on the dorsal and anal fin pterygiophores and on the dorsal, anal and pelvic fin spines; small but not plate-like distal expansions on the dorsal and haemal spines of the fourth preural centrum; the presence of autogenous hypurals; and a squamation that extends anteriorly onto the occipital and otic regions but not onto the cheeks. In terms of its general morphological traits, it resembles Leiognathoides altapinna, a species that has been reported from contemporary localities in Switzerland and Russia, although there are also some deviations that may be indicative of a different species. However, with the available materials, it is difficult to decide whether these differences are of taxonomic significance, so the new record is assigned to the genus Leiognathoides as cf. L. altapinna. The Oligocene specimens from France as well as the Lower Miocene specimens from the Czech Republic clearly belong to different taxa and probably not to the genus Leiognathoides at all. With regard to the palaeoecological and palaeogeographical framework, the new record indicates a tropical to subtropical climate and a waterway connection with the eastern Paratethys.     

Dactylogyridae (Monogenea) from the gills of Iheringichthys labrosus (Osteichthyes: Pimelodidae) from the upper Paraná River floodplain,Brazil, with the proposal of Pseudovancleaveus n. g

Two new species of Demidospermus Suriano, 1983 and a new genus, Pseudovancleaveus, and species are described from the gills of Iheringichthys labrosus (Pimelodidae). The fishes were collected from the upper Paraná River floodplain, Brazil. D. mandi n. sp. is characterised by the distal region of the copulatoty organ having an expanded bulb and D. labrosi n. sp. by the copulatory organ having a funnel-shaped proximal extremity. The latter species also has an accessory piece comprising a variable sheath enclosing the distal shaft of the copulatory organ and two anterolateral structures resembling irregular spheres. Pseudovancleaveus paranaensis. n. g., n. sp. is characterised by a sinistral vagina, overlapping gonads, a copulatory ligament, anchors without a fold on the base and hooks with slightly inflated shanks. A new combination, Pseudovancleaveus platensis, is proposed for Vancleaveus platensis Suriano & Incorvaia, 1995.     

Absolute C-14 dates of the profiles from the Zbudovská blata marshes (Southern Bohemia)

Additional C-14 dates to the pollen diagrams from the Zbudovská blata marshes (see Rybní?ková, Rybní?ek et Jankovská 1975) are published. The dates support the previous hypothesis of a stratigraphic hiatus for the middle Holocene era.     

Thermal biology of the Central Asian blunt-nosed viper (Macrovipera lebetina turanica) from Nuratau Crest and the Chernov blunt-nosed viper (Macrovipera lebetina černovi) from Western Kysylkum

The ecology of the Central Asian blunt-nosed viper (Macrovipera lebetina turanica) inhabiting the Nuratau Crest of Uzbekistan is described. The temperature conditions of the environment and the spatialtemporal structure of the viper activity are represented, which made it possible to find some of thermobiological characteristics. The temperature diapason of full activity of this viper constitutes approximately 17–34°C. The temperature of thermostabilization is in the range of 26–31°C, nocturnal temperatures are elevated from 9–15°C to 18–23°C in spring and summer, respectively, and diurnal body temperatures are decreased from 18–22°C to 10–15°C. Feeding and digestion are normal in blunt-nosed vipers at 25°C, which is below the diurnal temperature variation. In spring, the light phase duration is rapidly increased from 3–6 h to 14 h or more. This length of time and the large diurnal variation in the body temperature from 18°C to 20–22°C facilitate active and efficient coupling. Later, the diurnal body temperature is decreased to 13–18°C, which facilitates successful recovery in males and pregnancy in females. Plots for the average viper body temperature in different seasons are represented. The thermobiological characteristics of the bluntnosed viper of Macrovipera lebetina ěrnovi are similar to M. l. turanica.     

A new peirosaurid (Crocodilyformes) from the Late Cretaceous (Turonian–Coniacian) of Patagonia,Argentina

Peirosauridae is composed of mid- to large-sized terrestrial mesoeucrododylian crocodyliforms distributed throughout Gondwanan landmasses. Here we describe a new peirosaurid that comes from the upper levels of the Portezuelo Formation (Turonian–Coniacian, Upper Cretaceous) from Loma de la Lata, Neuquén Province, Argentina. This specimen consists of some associated bones belonging to a single individual. In order to facilitate comparisons, we recognise two different peirosaurid morphotypes based on skull shape: broad- and narrow-snouted taxa. The new taxon may be related to broad-snouted taxa, especially Gasparinisuchus peirosauroides. The new taxon here reported has strong heterodont dentition when compared with other peirosaurids. As in related forms, the fourth dentary tooth is caniniform, very large, acute and transversely compressed (much more than other peirosaurids), and the anterior dentary teeth have less globular, sharp serrated crowns. Large interalveolar spaces are present between both mandibular and maxillary teeth, a trait only observed on the new taxon. With this addition, we elevate the number of Patagonian peirosaurids to four. Moreover, it represents together with Lomasuchus palpebrosus the second peirosaurid species described for the Portezuelo Formation.     

Clestobothrium neglectum (Lönnberg, 1893) n. comb. (Cestoda: Bothriocephalidae) from the tadpole fish Raniceps raninus (L.) (Gadidae) from Sweden

Clestobothrium neglectum (Lönnberg, 1893) n. comb. is redescribed from specimens previously deposited in The Natural History Museum, London, UK by Dr David I. Gibson obtained from the intestine of the tadpole fish Raniceps raninus (Gadidae) collected from off the western coast of Sweden, near Kristineberg. C. neglectum resembles C. crassiceps (Rudolphi, 1819), the type- and only species currently recognised in the genus, but differs in having fine spiniform-like structures that are likely microtriches covering the posterior fourth of the scolex and all proglottids, a highly folded tegument forming numerous longitudinal ridges on both the dorsal and ventral surfaces of the proglottids giving them a scalloped appearance, a somewhat smaller egg (68 × 35 vs 75 × 40 μm), a U-shaped rather than H-shaped ovary and more testes (70–85 vs 40–50 per proglottid). C. neglectum is also compared to two species with similar scoleces that were previously assigned to Clestobothrium, Bothriocephalus acheilognathi Yamaguti, 1934 and B. kivuensis Baer &; Fain, 1958 (considered to be synonymous with B. acheilognathi by Pool, 1987). This is the first report of a species of Clestobothrium Lühe, 1899 (Bothriocephalidae) from a gadid fish.     

First occurrence of Palaeotheriidae (Perissodactyla) from the late–middle Eocene of eastern Thrace (Greece)

A detailed assessment of postcranial fossils collected at Balouk Keui (Thrace, Greece) in the mid-19th Century by the naturalist Auguste Viquesnel enabled us to identify the material as pertaining to Palaeotherium sp., cf. P. magnum, which constitutes the easternmost occurrence of the genus during the Eocene. We have constrained the geographic and stratigraphic provenance of the fossil by reassessing information about Viquesnel's itinerary and observations. Although the exact age of the fossil remains uncertain, the occurrence of a palaeothere in the Thrace Basin during the Eocene indicates a wider geographic distribution for the genus, which had previously been restricted to western and central Europe. The palaeothere of Balouk Keui confirms that the palaeogeographic range of this group included the Balkans during the middle–late Eocene. This discovery also shows that at least intermittent land connections between western Europe, Southeast Asia, and perhaps Central Iran facilitated mammalian dispersal during the middle–late Eocene, before the famous Grande Coupure.     

Macroscopic plant remains from the base of the Ust’-Pinega formation (Upper Vendian of the Arkhangelsk Region)

Plant macrofossil remains from the Lyamtsa and Arkhangelsk beds of the Ust’-Pinega Formation (Vendian) are reported for the first time. Three new taxa of vendotaenid algae showing cellular parenchymatous morphology are described: Archyfasma lamellata sp. nov., Favosiphycus wukii gen. et sp. nov., and Gandvikia caudata gen. et sp. nov. Phytostratigraphic characteristics allow the author to correlate the deposits under study with the base of the Mogilev Formation (Vendian of Podolia). A distinctive Lower Redkino vendotaenid flora is described for the first time. It is shown to precede the Upper Redkino Eoholynialen flora.