Structure et ontogenèse du thalle squamuleux du lichen Endocarpon pusillum (Pyrénolichens, Verrucariacées)

1988 ◽  
Vol 66 (11) ◽  
pp. 2118-2127 ◽  
Author(s):  
Jean Wagner ◽  
Marie-Agnès Letrouit-Galinou
Keyword(s):  
Structural Data ◽  
Morphological Characters ◽  
Fruiting Bodies ◽  
The One ◽  
Topographical Relation

Observations concerning morphology, structure, and ontogeny of the thallus of a squamulous species, Endocarpon pusillum Hedw., are presented. The latter is composed of squamules, most of which are interconnected by a well developed network of rhizomorphs. Four types of squamules have been distinguished according to their morphological characters and their location with regard to rhizomorphs. The squamules of E. pusillum are characterized by the lack of lacunae and the presence of numerous rhizomorphic-like hyphae in the medulla, which are in topographical relation with the hyphae of the rhizomorphs. Morphological and structural data allowed us to follow an ontogenic continuum from the smallest squamules, i.e. the least differentiated, to the one bearing fruiting-bodies, which show numerous rhizomorphs.

scholarly journals Screening of homokaryotic protoclones of Agaricus bisporus (J. Lge) Imbach by colony characters and ISSR markers

2010 ◽  
Vol 39 (1) ◽  
pp. 119-122 ◽  
Author(s):  
Mahmudul Islam Nazrul ◽  
Fan Xiao Lin ◽  
Bian Yin-Bing
Keyword(s):  
Simple Sequence Repeat ◽  
Agaricus Bisporus ◽  
Morphological Characters ◽  
Inter Simple Sequence Repeat ◽  
Issr Markers ◽  
Fruiting Bodies ◽  
Sequence Repeat ◽  
Slow Growing ◽  
Simple Sequence ◽  
Issr Primers

Among ten slow-growing protoclones of Agaricus bisporus (J. Lge) Imbach, all appressed colonies showed slower growth rate and spawn run, and inability to produce fruiting bodies in substrate. Seven of 40 inter-simple sequence repeat (ISSR) primers amplified 78 reproducible fragments, 48.93% were polymorphic, each producing 7 to 16 bands ranging from 0.10 to 2.10 kbp, sufficient to differentiate the protoclones from each other. Appressed protoclones were homoallelic at a number of loci that were heteroallelic in the parent, suggesting that they represented rare homokaryons. Thus, using morphological characters along with ISSR, polymorphisms could be useful for quick, easy, and accurate in distinguishing homo- and heterokaryotic isolates. Key words: Agaricus bisporus (J. Lge) Imbach; Homokaryon; ISSR; Protoclone DOI: 10.3329/bjb.v39i1.5537Bangladesh J. Bot. 39(1): 119-122, 2010 (June)

scholarly journals Morphology and stable isotope analysis demonstrate different structuring of bat communities in rainforest and savannah habitats

2018 ◽  
Vol 5 (12) ◽  
pp. 180849 ◽  
Author(s):  
Ara Monadjem ◽  
Adam Kane ◽  
Peter Taylor ◽  
Leigh R. Richards ◽  
Grant Hall ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Niche Breadth ◽  
Isotope Analysis ◽  
Morphological Characters ◽  
Trophic Levels ◽  
Species Packing ◽  
Dietary Niche ◽  
The One ◽  
Ellipse Area

Bats play important ecological roles in tropical systems, yet how these communities are structured is still poorly understood. Our study explores the structure of African bat communities using morphological characters to define the morphospace occupied by these bats and stable isotope analysis to define their dietary niche breadth. We compared two communities, one in rainforest (Liberia) and one in savannah (South Africa), and asked whether the greater richness in the rainforest was due to more species ‘packing’ into the same morphospace and trophic space than bats from the savannah, or some other arrangement. In the rainforest, bats occupied a larger area in morphospace and species packing was higher than in the savannah; although this difference disappeared when comparing insectivorous bats only. There were also differences in morphospace occupied by different foraging groups (aerial, edge, clutter and fruitbat). Stable isotope analysis revealed that the range of δ 13 C values was almost double in rainforest than in savannah indicating a greater range of utilization of basal C 3 and C 4 resources in the former site, covering primary productivity from both these sources. The ranges in δ 15 N, however, were similar between the two habitats suggesting a similar number of trophic levels. Niche breadth, as defined by either standard ellipse area or convex hull, was greater for the bat community in rainforest than in savannah, with all four foraging groups having larger niche breadths in the former than the latter. The higher inter-species morphospace and niche breadth in forest bats suggest that species packing is not necessarily competitive. By employing morphometrics and stable isotope analysis, we have shown that the rainforest bat community packs more species in morphospace and uses a larger niche breadth than the one in savannah.

scholarly journals Discovery of a hidden transient state in all bromodomain families

2021 ◽  
Vol 118 (4) ◽  
pp. e2017427118
Author(s):  
Lluís Raich ◽  
Katharina Meier ◽  
Judith Günther ◽  
Clara D. Christ ◽  
Frank Noé ◽  
...  
Keyword(s):  
Posttranslational Modifications ◽  
Rational Design ◽  
General Structure ◽  
Transient State ◽  
Structural Data ◽  
Binding Mode ◽  
Dynamical Features ◽  
The One ◽  
Markov State Modeling ◽  
Dynamics Simulations

Bromodomains (BDs) are small protein modules that interact with acetylated marks in histones. These posttranslational modifications are pivotal to regulate gene expression, making BDs promising targets to treat several diseases. While the general structure of BDs is well known, their dynamical features and their interplay with other macromolecules are poorly understood, hampering the rational design of potent and selective inhibitors. Here, we combine extensive molecular dynamics simulations, Markov state modeling, and available structural data to reveal a transiently formed state that is conserved across all BD families. It involves the breaking of two backbone hydrogen bonds that anchor the ZA-loop with the αA helix, opening a cryptic pocket that partially occludes the one associated to histone binding. By analyzing more than 1,900 experimental structures, we unveil just two adopting the hidden state, explaining why it has been previously unnoticed and providing direct structural evidence for its existence. Our results suggest that this state is an allosteric regulatory switch for BDs, potentially related to a recently unveiled BD-DNA–binding mode.

scholarly journals Discovery of a hidden transient state in all bromodomain families

2020 ◽  
Author(s):  
Lluís Raich ◽  
Katharina Meier ◽  
Judith Günther ◽  
Clara D. Christ ◽  
Frank Noé ◽  
...  
Keyword(s):  
Rational Design ◽  
General Structure ◽  
Transient State ◽  
Structural Data ◽  
Binding Mode ◽  
Post Translational Modifications ◽  
Dynamical Features ◽  
The One ◽  
Markov State Modeling ◽  
Dynamics Simulations

ABSTRACTBromodomains (BDs) are small protein modules that interact with acetylated marks in histones. These post-translational modifications are pivotal to regulate gene expression, making BDs promising targets to treat several diseases. While the general structure of BDs is well known, their dynamical features and their interplay with other macromolecules are poorly understood, hampering the rational design of potent and selective inhibitors. Here we combine extensive molecular dynamics simulations, Markov state modeling and structural data to reveal a novel and transiently formed state that is conserved across all BD families. It involves the breaking of two backbone hydrogen bonds that anchor the ZA-loop with the αA helix, opening a cryptic pocket that partially occludes the one associated with histone binding. Our results suggest that this novel state is an allosteric regulatory switch for BDs, potentially related to a recently unveiled BD-DNA binding mode.

Revisiting the absolute chirality and polymorphism of (–)-Istanbulin A

2020 ◽  
Vol 76 (9) ◽  
pp. 914-920
Author(s):  
Luz Arancibia ◽  
Mariana Naspi ◽  
Graciela Pucci ◽  
Maricel Rodriguez ◽  
Florencia Di Salvo
Keyword(s):  
Literature Search ◽  
Structural Data ◽  
2D Nmr ◽  
X Ray Diffraction ◽  
Crystal Forms ◽  
X Ray ◽  
Spectroscopic Information ◽  
The One ◽  
Absolute Chirality ◽  
Antimicrobial And Antifungal Activities

The terpenoid (−)-Istanbulin A is a natural product isolated from Senecio filaginoides DC, one of the 270 species of Senecio (Asteraceae) which occurs in Argentina. The structure and absolute configuration of this compound [9a-hydroxy-3,4a,5-trimethyl-4a,6,7,8a,9,9a-hexahydro-4H,5H-naphtho[2,3-b]-furan-2,8-dione or (4S,5R,8R,10S)-1-oxo-8β-hydroxy-10βH-eremophil-7(11)-en-12,8β-olide, C15H20O4] were determined by single-crystal X-ray diffraction studies. It proved to be a sesquiterpene lactone showing an eremophilanolide skeleton whose chirality is described as 4S,5R,8R,10S. Structural results were also in agreement with the one- and two-dimensional (1D and 2D) NMR and HR–ESI–MS data, and other complementary spectroscopic information. In addition, (−)-Istanbulin A is a polymorph of the previously reported form of (−)-Istanbulin A, form I; thus, the title compound is denoted form II or polymorph II. Structural data and a literature search allowed the chirality of Istanbulin A to be revisited. The antimicrobial and antifungal activities of (−)-Istanbulin A, form II, were evaluated in order to establish a reference for future comparisons and applications related to specific crystal forms of Istanbulins.

Ixodes inopinatus and Ixodes ricinus (Acari: Ixodidae) Are Sympatric Ticks in North Africa

2019 ◽  
Vol 57 (3) ◽  
pp. 952-956 ◽  
Author(s):  
Hend Younsi ◽  
Wasfi Fares ◽  
Saifedine Cherni ◽  
Khalil Dachraoui ◽  
Walid Barhoumi ◽  
...  
Keyword(s):  
Ixodes Ricinus ◽  
North Africa ◽  
Morphological Characters ◽  
Published Data ◽  
Northern Tunisia ◽  
Humid Area ◽  
Ixodes Ticks ◽  
The One ◽  
Rrna Sequences ◽  
16S Rrna Sequences

Abstract In the present study, we report the sympatric occurrence of Ixodes ricinus (Linnaeus, 1758) and Ixodes inopinatus (Estrada-Peña, Nava, and Petney, 2014) in Tunisia. In total, 173 adult Ixodes ticks were collected from four sites (El Jouza, Tamra, Aïn Soltan, and Jbel Zaghouan) between February and April 2017, a period corresponding to the peak of activity of I. ricinus in North Africa. The morphological characters corresponded to both species; thus, we generated a total of 28 16S rRNA sequences and compared them with previously published data in GenBank. The two species were sympatric in Tamra, Aïn Soltan, and El Jouza, whereas collections in Jbel Zaghouan only yielded I. inopinatus. These results indicate that the two taxa are widespread in the humid area of northern Tunisia. The one tick collected in Jbel Zaghouan suggests that the distribution of at least I. inopinatus might extend to the sub-humid area. More studies are needed to fully comprehend the systematic status of the two taxonomic entities using multiple molecular markers and morphological characters; integrating these two identification methods are a necessary step toward a better understanding of the ecology and epidemiology of tick-borne diseases in Tunisia.

Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXXIV Synthesis and Structure of the 1 : 1 Adduct of Silver(I) Nitrate with Triphenylstibine

1997 ◽  
Vol 50 (6) ◽  
pp. 671 ◽  
Author(s):  
Effendy ◽  
John D. Kildea ◽  
Allan H. White
Keyword(s):  
Single Crystal ◽  
Structure Determination ◽  
Related Species ◽  
Room Temperature ◽  
Structural Data ◽  
Lewis Base ◽  
One Dimensional ◽  
X Ray ◽  
The One

The synthesis and room-temperature single-crystal X-ray structure determination of the 1 : 1 adduct of silver(I) nitrate with triphenylstibine, AgNO3/SbPh3 (1 : 1), is recorded, being monoclinic, Cc,a 12·824(2), b 15·794(4),c 9·796(2) Å, β 117·50(1)°, Z= 4; conventional R on F was 0·030 for 2881 independent ‘observed’ (I > 3σ(I)) reflections. The complex is a one-dimensional polymer with bridging nitrate groups, resembling in this respect its phosphine and arsine analogues. The completion of this study, along with related species recorded in accompanying papers, means that full structural data are now available for the complete array AgNO3/EPh3 (1 : n), E = P, As, Sb, n = 1–4, with the one exception of E = Sb, n = 2.

The Temperature-Variable Geometry of the Pseudo-Octahedral CuO6 Entity in Bis(methoxyacetato) diaquo-Cooper(II) - a Single Crystal EPR Study

1987 ◽  
Vol 42 (12) ◽  
pp. 1500-1506 ◽  
Author(s):  
Bernd Jakob ◽  
Dirk Reinen
Keyword(s):  
Single Crystal ◽  
Structural Data ◽  
Continuous Transition ◽  
Teller Distortion ◽  
Different Temperatures ◽  
Jahn Teller ◽  
Bonding Properties ◽  
Temperature Variable ◽  
State Potential ◽  
The One

AbstractThe Cu-O bond lengths in the pseudooctahedral bis(methoxvacetato)diaquo-copper(II) com­plex are determined by the Jahn-Teller effect on the one hand and by the bonding properties of the three different oxygen ligator atoms (from a carboxylate. water and ether group) on the other. It is derived from EPR single crystal and powder investigations between 4.2 and 350 K. that the system becomes fluxional above =120 K due to a continuous transition from a static to a (par­tially) dynamic Jahn-Teller distortion. A model is presented, which allows to correlate the EPR results with the Cu-O spacings. if they are calibrated with structural data at two different temperatures. The structure of the ground state potential surface of Cu2+ is derived from the spectroscopic data.

scholarly journals Differentiation between two epilittoral species, Scutovertex arenocolus spec. nov. and Scutovertex pilosetosus Polderman (Acari: Oribatida) from different European coasts

Zootaxa ◽  
2009 ◽  
Vol 2153 (1) ◽  
pp. 35-54 ◽  
Author(s):  
TOBIAS PFINGSTL ◽  
SYLVIA SCHÄFFER ◽  
ERNST EBERMANN ◽  
GUENTHER KRISPER
Keyword(s):  
North Sea ◽  
Principal Component ◽  
Morphological Characters ◽  
Closely Related Species ◽  
The North ◽  
Baltic Coast ◽  
The North Sea ◽  
The One ◽  
The Baltic ◽  
Littoral Species

Scutovertex arenocolus spec. nov. living in the sandy shore of the Baltic coast is described. Additionally, a closely related species, S. pilosetosus, occurring in marsh habitats of the North Sea coast, is redescribed in detail. Both species show a similar habitus. Scutovertex arenocolus differs from S. pilosetosus in the length of body, cusps and notogastral setae, in the ridge on mentum as well as in a different exochorion structure of the eggs. A morphometric analysis of 14 morphological characters confirmed distinctly shorter cusps and notogastral setae in S. arenocolus. Additionally, a principal component analysis performed with 17 morphological traits provided a clear separation of these two species and of S. minutus. The results of these analyses lead to the conclusion that earlier reports of S. minutus in the coastal zone of the Atlantic, the Baltic and the North Sea should be assigned to the one or the other of these two littoral species.

scholarly journals Ectomycorrhizal Fungi on South Kalimantan Serpentine Soil

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Rudy Hermawan ◽  
Witiyasti Imaningsih ◽  
Badruzsaufari Badruzsaufari
Keyword(s):  
Heavy Metals ◽  
Ectomycorrhizal Fungi ◽  
Morphological Characters ◽  
Ectomycorrhizal Fungus ◽  
Serpentine Soil ◽  
Fruiting Bodies ◽  
Genus Identification ◽  
Manganese Chromium ◽  
Cobalt And Nickel

Serpentine soil contains highly heavy metals, such as manganese, chromium, cobalt, and nickel,which could bean inappropriate growthmediaofmostplants. Someplants thatfound able to grow optimally on South Kalimantan serpentine soil have been known to do association with ectomycorrhizal fungi. This research aimed to obtain and characterize mushrooms assumed as ectomycorrhizal fungi indigenous South Kalimantan serpentine soil. This study used field exploration of fungal fruiting bodies and identified the genus based on morphological characters of fruiting bodies such as shape, size, and ornamentation, which are unique for the genus identification, then compared the characteristics on mushroomexpert.com. The mushrooms were also confirmed of genera assumed as ectomycorrhizal fungi based on mycorrhizas.info. Seven fruiting bodies were obtained and classified as Cantharellus (Ct), Chlorophyllum (Ch1 and Ch2), Lycoperdon (Ly), Ramaria (Rm1 and Rm2), and Thelephora (Tp). The results showed that all of those fruiting bodies belong to Basidiomycetes. There were 4 genera of Cantharellus, Lycoperdon, Ramaria, and Thelephora, assumed as ectomycorrhizal fungi. But Chlorophyllum genus was never reported as ectomycorrhizal fungus

Sign in / Sign up

Export Citation Format

Share Document