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31.
Tarek Slatni Imen Ben Salah Saber Kouas Chedly Abdelly 《Journal of plant research》2014,127(3):455-465
Iron is vital for the establishment and function of symbiotic root nodules of legumes. Although abundant in the environment, Fe is often a limiting nutrient for plant growth due to its low solubility and availability in some soils. We have studied the mechanism of iron uptake in the root nodules of common bean to evaluate the role of nodules in physiological responses to iron deficiency. Based on experiments using full or partial submergence of nodulated roots in the nutrient solution, our results show that the nodules were affected only slightly under iron deficiency, especially when the nodules were submerged in nutrient solution in the tolerant cultivar. In addition, fully submerged root nodules showed enhanced acidification of the nutrient solution and showed higher ferric chelate reductase activity than that of partially submerged roots in plants cultivated under Fe deficiency. The main results obtained in this work suggest that in addition to preferential Fe allocation from the root system to the nodules, this symbiotic organ probably develops some mechanisms to respond to iron deficiency. These mechanisms were implied especially in nodule Fe absorption efficiency and in the ability of this organ to take up Fe directly from the medium. 相似文献
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Imen?MessaoudiEmail author Afef?Elloumi?Oueslati Zied?Lachiri 《EURASIP Journal on Bioinformatics and Systems Biology》2014,2014(1):16
Challenging tasks are encountered in the field of bioinformatics. The choice of the genomic sequence’s mapping technique is one the most fastidious tasks. It shows that a judicious choice would serve in examining periodic patterns distribution that concord with the underlying structure of genomes. Despite that, searching for a coding technique that can highlight all the information contained in the DNA has not yet attracted the attention it deserves. In this paper, we propose a new mapping technique based on the chaos game theory that we call the frequency chaos game signal (FCGS). The particularity of the FCGS coding resides in exploiting the statistical properties of the genomic sequence itself. This may reflect important structural and organizational features of DNA. To prove the usefulness of the FCGS approach in the detection of different local periodic patterns, we use the wavelet analysis because it provides access to information that can be obscured by other time-frequency methods such as the Fourier analysis. Thus, we apply the continuous wavelet transform (CWT) with the complex Morlet wavelet as a mother wavelet function. Scalograms that relate to the organism Caenorhabditis elegans (C. elegans) exhibit a multitude of periodic organization of specific DNA sequences. 相似文献
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Imen Bousrih Mejda El Kateb Mohammed Beji Fréderic Guittard Thierry Darmanin 《仿生工程学报(英文版)》2021,18(1):65-76
Controlling the shape of surface nanostructures is fundamental for various potential applications for cxamples,in water harvesting systems,liquid transportation or oil/water separation membranes.In this paper,the creation of porous surface structures is made by a process called templateless electropolymerization,in which water(H20)is oxidizedreduced to form gas(O2/H2)bubbles onto the surfaces and acting as soft template for the polymer growth.Keeping the monomer(thieno[3,4-b]lhiophene)and the substituent(pyrene)constant,we demonstrate how a flexible PEG spacer can affect the structure shape.When the PEG spacer increases,the structures change frorm nanotubes(1D growth)to nanoribbons(2D)and after to hollow nanospheres(3D),which also affeets the wettig propertics. 相似文献
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Hamidah Idris Imen Nouioui Wasu Pathom-aree Jean Franco Castro Alan T. Bull Barbara A. Andrews Juan A. Asenjo Michael Goodfellow 《Antonie van Leeuwenhoek》2018,111(9):1523-1533
The taxonomic position of a novel Amycolatopsis strain isolated from a high altitude Atacama Desert subsurface soil was established using a polyphasic approach. The strain, isolate H5T, was shown to have chemical properties typical of members of the genus Amycolatopsis such as meso-diaminopimelic acid as the diamino acid in the cell wall peptidoglycan, arabinose and galactose as diagnostic sugars and MK-9(H4) as the predominant isoprenologue. It also has cultural and morphological properties consistent with its classification in the genus, notably the formation of branching substrate hyphae which fragment into rod-like elements. 16S rRNA gene sequence analyses showed that the strain is closely related to the type strain of Amycolatopsis mediterranei but could be distinguished from this and other related Amycolatopsis strains using a broad range of phenotypic properties. It was separated readily from the type strain of Amycolatopsis balhymycina, its near phylogenetic neighbour, based on multi-locus sequence data, by low average nucleotide identity (92.9%) and in silico DNA/DNA relatedness values (51.3%) calculated from draft genome assemblies. Consequently, the strain is considered to represent a novel species of Amycolatopsis for which the name Amycolatopsis vastitatis sp. nov. is proposed. The type strain is H5T (= NCIMB 14970T = NRRL B-65279T). 相似文献
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Salih Saricaoglu Imen Nouioui Hilal Ay Hayrettin Saygin Kadriye Inan Bektas Kiymet Guven Demet Cetin Hans-Peter Klenk Kamil Isik Nevzat Sahin 《Antonie van Leeuwenhoek》2018,111(11):2051-2059
Strain H2R21T, a novel actinobacterium, isolated from a forest soil sample collected from Heybeliada, Istanbul, Turkey, and a polyphasic approach was used for characterisation of the strain. Chemotaxonomic and morphological characterisation of strain H2R21T indicated that it belongs to the genus Nonomuraea. 16S rRNA gene sequence similarity showed that the strain is closely related to Nonomuraea purpurea 1SM4-01T (99.1%) and Nonomuraea solani CGMCC 4.7037T (98.4%). DNA–DNA relatedness values were found to be lower than 70% between the isolate and its phylogenetic neighbours N. purpurea 1SM4-01T, N. solani CGMCC 4.7037T and Nonomuraea rhizophila YIM 67092T. The whole cell hydrolysates of strain H2R21T were found to contain meso-diaminopimelic acid as the diagnostic diamino acid and glucose, madurose, mannose and ribose as the cell sugars. The polar lipids were identified as phosphatidylglycerol, diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, dihydroxy-phosphatidylethanolamine, phosphatidylinositol, glycophosphatidylinositol, two glycophospholipids and two unidentified lipids. The predominant menaquinones were identified as MK-9(H4) and MK-9(H6). The major fatty acids were found to be iso-C16:0, iso-C16:0 2OH and C17:0 10-methyl. On the basis of DNA–DNA relatedness data and some phenotypic characteristics, it is evident that strain H2R21T can be distinguished from the closely related species in the genus Nonomuraea. Thus, it is concluded that strain H2R21T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea insulae sp. nov. is proposed. The type strain is H2R21T (= DSM 102915T = CGMCC 4.7338T = KCTC 39769T). 相似文献
36.
Chamseddine Derabli Imen Boualia Ahmed B. Abdelwahab Raouf Boulcina Chawki Bensouici Gilbert Kirsch Abdelmadjid Debache 《Bioorganic & medicinal chemistry letters》2018,28(14):2481-2484
In this work, we describe the preparation of some new Tacrine analogues modified with a pyranopyrazole moiety. A one-pot multicomponent reaction of 3-methyl-1H-pyrazol-5(4H)-one, aryl(or hetero)aldehydes, malononitrile and cyclohexanone involving a Friedländer condensation led to the title compounds. The synthesized heterocyclic analogues of this molecule were evaluated in vitro for their AChE and BChE inhibitory activities in search for potent cholinesterase enzyme inhibitors. Most of the synthesized compounds displayed remarkable AChE inhibitory activities with IC50 values ranging from 0.044 to 5.80?µM, wherein compounds 5e and 5j were found to be most active inhibitors against AChE with IC50 values of 0.058 and 0.044?µM respectively. Molecular modeling simulation on AChE and BChE receptors, showed good correlation between IC50 values and binding interaction template of the most active inhibitors docked into the active site of their relevant enzymes. 相似文献
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Imen Saadaoui Maryam Al Emadi Touria Bounnit Kira Schipper Hareb Al Jabri 《Journal of applied phycology》2016,28(4):2233-2240
The Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM) is a unique resource containing a diverse collection of microalgae and cyanobacteria, isolated from the Qatar desert environment. In order to ensure maximum preservation of this resource, a number of cryopreservation techniques were applied to various strains, and the preservation effectiveness (cell viability and lipid productivity) was determined. The conditions tested were direct, passive, and freeze-cooling cryopreservation (technique), dimethyl sulfate and methanol (cryoprotectant), and 5 and 10 % cryoprotectant concentrations over storage durations of up to 1 year. It was shown that the cryopreservation regime is strain dependent, and strains belonging to the same genera can have different requirements. On the other hand, neutral lipid estimation, via Nile red fluorescence determination of pre- and post-cryopreserved microalgae isolates, confirmed that the lipid production is affected by the applied cryopreservation method. 相似文献
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P Normand J Gury P Pujic B Chouaia E Crotti L Brusetti D Daffonchio B Vacherie V Barbe C Médigue A Calteau F Ghodhbane-Gtari I Essoussi I Nouioui I Abbassi-Ghozzi M Gtari 《Journal of bacteriology》2012,194(17):4773-4774
Here we report the full genome sequence of Modestobacter marinus strain BC501, an actinobacterial isolate that thrives on stone surfaces. The generated chromosome is circular, with a length of 5.57 Mb and a G+C content of 74.13%, containing 5,445 protein-coding genes, 48 tRNAs, and 3 ribosomal operons. 相似文献