Search results for "structural"
showing 10 items of 5047 documents
Structure of keyhole limpet hemocyanin type 1 (KLH1) at 15 Å resolution by electron cryomicroscopy and angular reconstitution † 1 †This article is de…
1997
Abstract A three-dimensional reconstruction of keyhole limpet hemocyanin type 1 (KLH1) has been obtained using electron cryomicroscopy at liquid helium temperatures and single particle image processing. The use of a high-contrast embedding medium, 1% (w/v) glucose and 2% (w/v) ammonium molybdate (pH 7.0), enables high-resolution electron micrographs to be recorded close to focus, i.e. with excellent transfer of high-resolution information, while maintaining enough image contrast to localise the individual macromolecules in the images. When low-pass filtered to ∼45 A resolution, the new 15 A resolution reconstruction is very similar to the earlier reconstructions of gastropodan hemocyanins o…
A new species of Crepidostomum (Allocreadiidae: Digenea) from northeastern Finland, with comments on its possible origin
1988
Crepidostomum wikgreni n. sp. is described from the gall-bladder and intestine of the whitefish Coregonus acronius in Lake Yli-Kitka in NE Finland. It is morphologically similar to Crepidostomum farionis, with which it occurs sympatrically and sometimes concurrently; but it differs in that the eggs are much larger, i.e. 96±6.5 μm mean-length, as opposed to 71±4.7 μm mean-length for C. farionis in the same host and locality. It is suggested that the new species has arisen from C. farionis after deglaciation and since c. 8,400 BP, at which time the waters of the Lake Kitka System were isolated from those in the rest of Finland and flowed eastwards into the White Sea Basin. The isolation of th…
Fragmentary remains of Odontocetes (Cetacea, Mammalia) from the Miocene of the Lower Tagus Basin (Portugal)
2021
This first systematic account of the scarcely studied Miocene cetaceans from Portugal describes 17 previously unpublished odontocete specimens from the Lower Tagus Basin. In spite of their fragmentary nature, at least a familial assignment was accomplished for most, and some were even tentatively ascribed to known genera: the Physeteridae are represented only by isolated teeth of “ Scaldicetus ” type; the Platanistidae by a tympanic not definitely assigned to a particular genus; the Eurhinodelphinidae by a lumbar vertebra and an atlas, both only tentatively referred to this family; and the Kentriodontidae comprise the most diversified forms, including rostral and mandibular fragments of a k…
Gravity-Driven Infiltration and Subsidence Phenomena in Posidonia oceanica Residues
2019
A simplified infiltration model for highly permeable porous media was introduced, assuming the matric potential gradient as negligible compared to the gravitational gradient. This model enabled us to determine the delay time, i.e., the time that the water front takes (from the beginning of rainfall) to reach the bottom of the highly permeable layer. Posidonia oceanica (Linnaeus) Delile residues were used as a porous media, in order to study the infiltration process that provides salt leaching under natural rainfall when these residues are arranged in a storage area, before reusing. By using a laboratory rainfall simulator, delay times were measured to verify the applicability of the aforeme…
Upper Givetian and Frasnian (Middle and Upper Devonian) conodonts from Ampriú (Aragonian Pyrenees, Spain): global correlations and palaeogeographic r…
2012
This report describes for the first time a part of the Middle and Upper Devonian conodont sequence of the Sierra Negra Subfacies in the Aragonian Pyrenees (Spain), establishing the basis for further sound correlations both across the distinct Pyrenean facies and subfacies and on other relevant world areas. The description of 20 conodont taxa and their stratigraphical distribution permits recognition of two separate time intervals. The older one corresponds to the lower Upper Givetian (Middle Devonian), hermanni to crista- tus ectypus zones. The younger interval is uppermost Lower Frasnian to lower Middle Frasnian (Upper Devonian) and is equivalent to MN4-MN6 zones. The combination of litho-…
Phaenocompsopogon pustulatus n.gen.n. sp., a calcareous alga from the lacustrine rotliegend of the Saar-Nahe Basin (SW-Germany)
1992
Phaenocompsopogon pustulatus n. gen. n. sp. is a calcareous freshwater alga, probably of rhodophycean affinity. The fossils are mainly known from one locality in the Lower Permian of the Saar-Nahe Basin. The algal remains form a packstone in the Reckweilerhof-Bank of the Altenglan Formation. The simple thallus branches irregularly y-shaped and is covered with abundant pustules. An axial canal is characteristic, as are distinct cell features of an inner and outer cortex surrounding a structureless medulla. Most fossils are silicified and often three-dimensionally preserved. The algae lived in a wave-dominated environment, probably in offshore shallow water. The limited occurrence suggests sp…
Review of the shore-fly genus Oedenopiforma (Diptera: Ephydridae)
2012
The shore-fly genus Oedenopiforma Cogan is reviewed, including new information on Oedenopiforma argentea (distribution), Oedenopiforma javana (comb. nov. and O. orientalis syn. nov.), and Oedenopiforma vockerothi (sp. nov. from United Arab Emirates). Structures of the male terminalia of these three species, a diagnosis of the genus, and a key to the included genera of Dryxini and species of Oedenopiforma are presented. Resume´—Nous revisons le genre Oedenopiforma Cogan chez les ephydrides et apportons de nouvelles informations sur Oedenopiforma argentea (repartition), Oedenopiforma javana (nouvelle combinaison et O. orientalis nouvelle synonymie )e tOedenopiforma vockerothi (nouvelle espece…
Conformational dynamics of full-length inducible human Hsp70 derived from microsecond molecular dynamics simulations in explicit solvent
2013
Human 70 kDa heat shock protein (hHsp70) is an ATP-dependent chaperone and is currently an important target for developing new drugs in cancer therapy. Knowledge of the conformations of hHsp70 is central to understand the interactions between its nucleotide-binding domain (NBD) and substrate-binding domain (SBD) and is a prerequisite to design inhibitors. The conformations of ADP-bound (or nucleotide-free) hHsp70 and ATP-bound hHsp70 was investigated by using unbiased all-atom molecular dynamics (MD) simulations of homology models of hHsp70 in explicit solvent on a timescale of .5 and 2.7 μs, respectively. The conformational heterogeneity of hHsp70 was analyzed by computing effective free-e…
Production, crystallization and preliminary X-ray analysis of the human integrin alpha1 I domain.
1999
Integrin α1β1 is one of the main collagen receptors in many cell types. A fast large-scale production, purification and crystallization method for the integrin α1 I domain is reported here. The α1 I domain was crystallized using the vapour-diffusion method with a reservoir solution containing a mixture of PEG 4000, sodium acetate, glycerol and Tris–HCl buffer. The crystals beong to the C2 space group, with unit-cell parameters a = 74.5, b = 81.9, c = 37.3 Å, α = γ = 90.0, β = 90.8°. The crystals diffract to 2.0 Å and a 94.2% complete data set to 2.2 Å has been collected from a single crystal with an R merge of 5.8%.
Identification of highly conserved genes: SNZ and SNO in the marine sponge Suberites domuncula: their gene structure and promoter activity in mammali…
2001
Abstract Recently, we reported that cells from the sponge Suberites domuncula respond to ethylene with an increase in intracellular Ca 2+ level [Ca 2+ ] i , and with an upregulation of the expression of (at least) two genes, a Ca 2+ /calmodulin-dependent protein kinase and the potential ethylene-responsive gene, termed SDSNZERR (A. Krasko, H.C. Schroder, S. Perovic, R. Steffen, M. Kruse, W. Reichert, I.M. Muller, W.E.G. Muller, J. Biol. Chem. 274 (1999)). Here, we describe for the first time that also mammalian (3T3) cells respond to ethylene, generated by ethephon, with an immediate and transient, strong increase in [Ca 2+ ] i . Next, the promoter for the sponge SDSNZERR gene was isolated …