scholarly journals Tertiary structure of tRNAPhe. A possible correlation between the structural functional unit of this tRNA and its exonic sequence

1984 ◽  
Vol 219 (1) ◽  
pp. 341-344
Author(s):  
R Malathi ◽  
N Yathindra
Keyword(s):  
Tertiary Structure ◽  
Functional Unit ◽  
Classical Domain ◽  
Structural Units ◽  
Close Inspection ◽  
Ribonucleic Acids ◽  
Domain Structures ◽  
Shape Structure ◽  
Trna Species ◽  
Exonic Sequence

It has been shown recently [Go (1981) Nature (London) 291, 90-92; Blake (1983) Trends Biochem Sci. 8, 11-13] that the exonic regions of the genes of proteins haemoglobin, lysozyme and immunoglobin correspond closely to the compactly folded structural units. Despite the absence of classical domain structures in tRNA compared with those found in several proteins, close inspection of certain features in the distance maps obtained for yeast tRNAPhe using the conformationally equivalent heminucleotide scheme reveals that a similar situation might also be present in ribonucleic acids such as tRNA species and the exonic sequences of their genes. Also it seems possible that certain segments of yeast tRNAPhe may be characterized as possessing a domain-like character, and this seems to provide stereochemical support for possible conservation of L-shape structure for tRNA species lacking the entire dihydrouridine arm such as those found in mitochondria.

scholarly journals Recognition of individual Escherichia coli transfer ribonucleic acids by 1-adenine-specific methyltransferase from rat liver

1978 ◽  
Vol 169 (1) ◽  
pp. 247-249 ◽  
Author(s):  
J Kraus
Keyword(s):  
Escherichia Coli ◽  
Rat Liver ◽  
Ribonucleic Acids ◽  
Trna Species ◽  
Trna Methyltransferase

Purified 1-adenine-specific tRNA methyltransferase from rat liver preferentially methylated Escherichia coli tRNA species containing the target adenylate residue in a G-T-psi-C-G-A-A-U-C sequence. The results of methylation of various tRNA species are discussed.

Novel Chemoenzymatic Synthesis of Azobenzene Functionalized Ribonucleic Acid

2000 ◽  
Vol 660 ◽  
Author(s):  
Sucharita Roy ◽  
Ramaswamy Nagarajan ◽  
Peichuan Wu ◽  
Sukant K. Tripathy ◽  
Jayant Kumar ◽  
...  
Keyword(s):  
Tertiary Structure ◽  
Covalent Attachment ◽  
Hydroxyl Group ◽  
Synthetic Approach ◽  
Buffer Solution ◽  
Ribonucleic Acids ◽  
Hydrocarbon Solvents ◽  
Rna Backbone ◽  
Device Applications

ABSTRACTRibonucleic acids, often called a biological jack of all trades, contribute intimately to every aspect of gene expression, including the synthesis of other polypeptide biocatalysts. The fundamental importance of recurring structural motifs and the kinetics and energetics of the complex secondary and tertiary structure of RNA have been shown to be intimately linked with its functions in vivo. We have developed a novel enzymatic synthetic approach for covalent attachment of photoresponsive units into the RNA backbone. The synthetic conditions of this approach are extremely mild, involving the reverse micellar solubilization of nucleic acid along with lipase in apolar hydrocarbon solvents. Lipase catalyzed acylation of the 2' hydroxyl group in the ribose sugars of the RNA molecule has been used to incorporate photo-isomerizable azobenzene groups into the RNA strands. This micellar approach was envisaged for RNA functionalization while maintaining the conformational integrity of the macromolecular backbone in neutral buffer solution. The modification of RNA using covalently attached chromophores or fluorophores can be extended to other biomacromolecular matrices leading to the development of more versatile photoactive biopolymers. The photo-isomerizable groups incorporated in the RNA molecule can serve as optical ‘handles’ for the manipulation of the conformation of RNA and open new opportunities for biophotonic device applications.

Tertiary Structure in Transfer Ribonucleic Acids

1966 ◽  
Vol 31 (0) ◽  
pp. 527-537 ◽  
Author(s):  
J. R. Fresco ◽  
A. Adams ◽  
R. Ascione ◽  
D. Henley ◽  
T. Lindahl
Keyword(s):  
Tertiary Structure ◽  
Ribonucleic Acids

scholarly journals Evaluating the Efficiency of Economic Incentives for Development of Shipbuilding Enterprises

2020 ◽  
Vol 11 (514) ◽  
pp. 205-211
Author(s):  
V. H. Rogov ◽  
Keyword(s):  
Vertical Integration ◽  
Functional Unit ◽  
Economic Incentives ◽  
Business Value ◽  
Structural Units ◽  
Economic Decisions ◽  
Target Indicator ◽  
Money Flows ◽  
The Impact ◽  
Ship Repair

A substantiation of economic decisions in the process of using incentives and adapting to changes on the part of management necessitates applying an integral target indicator for the development of enterprise. As a result of the research, it is proved that it is advisable to choose as such an indicator the value of the business, in particular by discounting money flows. It is substantiated that in order to evaluate the efficiency of stimulating the development of the shipbuilding enterprise, the application of the revenue approach appears to be rational. Both the Ukrainian and foreign experience of horizontal and vertical integration in shipbuilding is analyzed and it is proved that the formation of integrated diversified corporate structures is an urgent stimulus for the development of the shipbuilding enterprise. Some owners of shipbuilding enterprises of Ukraine use them to build a fleet for the needs of their other business: agricultural, metallurgical, etc. Certain enterprises become part of diversified companies engaged in ship repair and port activities. The efficiency of integration of shipbuilding enterprises should also be evaluated using business value indicators. It is necessary to determine the impact of incentives relating not only to shipbuilding, but also to ship repair, shipping, maritime and other activities – not only on a separate shipyard, but comprehensively on the entire association, a structural and functional unit of which the enterprise is. The effect of the introduction of incentives is determined on the example of shipbuilding and ship repair plant «Nibulon». Evaluating the impact of economic incentives on the proposed integral target indicator enables to establish the feasibility of implementing the overall strategy of the enterprise and facilitates the adoption of informed economic decisions both at the level of individual structural units and the enterprise in general.

scholarly journals Assembling multidomain protein structures through analogous global structural alignments

2019 ◽  
Vol 116 (32) ◽  
pp. 15930-15938 ◽  
Author(s):  
Xiaogen Zhou ◽  
Jun Hu ◽  
Chengxin Zhang ◽  
Guijun Zhang ◽  
Yang Zhang
Keyword(s):  
Tertiary Structure ◽  
Level Structure ◽  
Protein Structures ◽  
Target Domain ◽  
Multidomain Protein ◽  
Domain Structures ◽  
Density Maps ◽  
Multidomain Structure ◽  
Multiple Domains ◽  
Structure Assembly

Most proteins exist with multiple domains in cells for cooperative functionality. However, structural biology and protein folding methods are often optimized for single-domain structures, resulting in a rapidly growing gap between the improved capability for tertiary structure determination and high demand for multidomain structure models. We have developed a pipeline, termed DEMO, for constructing multidomain protein structures by docking-based domain assembly simulations, with interdomain orientations determined by the distance profiles from analogous templates as detected through domain-level structure alignments. The pipeline was tested on a comprehensive benchmark set of 356 proteins consisting of 2–7 continuous and discontinuous domains, for which DEMO generated models with correct global fold (TM-score > 0.5) for 86% of cases with continuous domains and for 100% of cases with discontinuous domain structures, starting from randomly oriented target-domain structures. DEMO was also applied to reassemble multidomain targets in the CASP12 and CASP13 experiments using domain structures excised from the top server predictions, where the full-length DEMO models showed a significantly improved quality over the original server models. Finally, sparse restraints of mass spectrometry-generated cross-linking data and cryo-EM density maps are incorporated into DEMO, resulting in improvements in the average TM-score by 6.3% and 12.5%, respectively. The results demonstrate an efficient approach to assembling multidomain structures, which can be easily used for automated, genome-scale multidomain protein structure assembly.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

Temperature Dependence of Magnetic Domains and Wall Structures

1972 ◽  
Vol 30 ◽  
pp. 496-497
Author(s):  
Sonoko Tsukahara ◽  
Tadami Taoka ◽  
Hisao Nishizawa
Keyword(s):  
Temperature Dependence ◽  
Domain Walls ◽  
Magnetic Domain ◽  
Iron Film ◽  
Objective Lens ◽  
Lorentz Microscopy ◽  
Domain Structures ◽  
Wall Structures ◽  
Crystal Films ◽  
Metallurgical Structure

The high voltage Lorentz microscopy was successfully used to observe changes with temperature; of domain structures and metallurgical structures in an iron film set on the hot stage combined with a goniometer. The microscope used was the JEM-1000 EM which was operated with the objective lens current cut off to eliminate the magnetic field in the specimen position. Single crystal films with an (001) plane were prepared by the epitaxial growth of evaporated iron on a cleaved (001) plane of a rocksalt substrate. They had a uniform thickness from 1000 to 7000 Å.The figure shows the temperature dependence of magnetic domain structure with its corresponding deflection pattern and metallurgical structure observed in a 4500 Å iron film. In general, with increase of temperature, the straight domain walls decrease in their width (at 400°C), curve in an iregular shape (600°C) and then vanish (790°C). The ripple structures with cross-tie walls are observed below the Curie temperature.

Torus Circumference and Thickness Parameters From a Linear DNA Size Series Suggest How Toruses Self-Assemble

1985 ◽  
Vol 43 ◽  
pp. 522-523
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Tertiary Structure ◽  
Dna Complexes ◽  
Tertiary Structures ◽  
Self Assembling ◽  
Double Stranded Dna ◽  
Calf Thymus ◽  
Dna Organization ◽  
Condensed Dna ◽  
Dna Size

Certain double stranded DNA bacteriophage and viruses are thought to have their DNA organized into large torus shaped structures. Morphologically, these poorly understood biological DNA tertiary structures resemble spermidine-condensed DNA complexes formed in vitro in the total absence of other macromolecules normally synthesized by the pathogens for the purpose of their own DNA packaging. Therefore, we have studied the tertiary structure of these self-assembling torus shaped spermidine- DNA complexes in a series of reports. Using freeze-etch, low Pt-C metal (10-15Å) replicas, we have visualized the microscopic DNA organization of both calf Thymus( CT) and linear 0X-174 RFII DNA toruses. In these structures DNA is circumferentially wound, continuously, around the torus into a semi-crystalline, hexagonal packed array of parallel DNA helix sections.

Coherent electron nanodiffraction from clean silver nano particles in a UHV STEM

1993 ◽  
Vol 51 ◽  
pp. 1058-1059
Author(s):  
J. Liu ◽  
M. Pan ◽  
G. E. Spinnler
Keyword(s):  
Supported Catalysts ◽  
Imaging Techniques ◽  
Nano Particles ◽  
Metal Particles ◽  
Shape Structure ◽  
Dynamical Simulations ◽  
Small Metal Particles ◽  
Extract Information

Small metal particles have peculiar chemical and physical properties as compared to bulk materials. They are especially important in catalysis since metal particles are common constituents of supported catalysts. The structural characterization of small particles is of primary importance for the understanding of structure-catalytic activity relationships. The shape and size of metal particles larger than approximately 5 nm in diameter can be determined by several imaging techniques. It is difficult, however, to deduce the shape of smaller metal particles. Coherent electron nanodiffraction (CEND) patterns from nano particles contain information about the particle size, shape, structure and defects etc. As part of an on-going program of STEM characterization of supported catalysts we report some preliminary results of CEND study of Ag nano particles, deposited in situ in a UHV STEM instrument, and compare the experimental results with full dynamical simulations in order to extract information about the shape of Ag nano particles.

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