scholarly journals Crystallographic Studies of Enzymes

Crystals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 6
Author(s):  
T. Doohun Kim ◽  
Kyeong Kyu Kim
Keyword(s):  
Chemical Reactions ◽  
Molecular Level ◽  
Biological Processes ◽  
Research Papers ◽  
Functional Aspects ◽  
Wide Range ◽  
New Directions ◽  
Living Organisms ◽  
And Function ◽  
Structural Aspects

Enzymes are biological catalysts, which work to accelerate chemical reactions at the molecular level in living organisms. They are major players in the control of biological processes such as replication, transcription, protein synthesis, metabolism, and signaling. Like inorganic catalysts, enzymes function by decreasing the activation energy of chemical reactions, thereby enhancing the rate of the reactions. Enzymes are widely used for chemical, food, pharmaceutical, medicinal, analytical, clinical, forensic, and environmental applications. Therefore, studies on their structure, mechanism, and function, using a wide range of experimental and computational methods, are necessary to understand better enzymes in biological processes. For this special issue, “Crystallographic Studies of Enzymes", we have collected research papers on enzymes with structural aspects and functional aspects; here we briefly discuss the contents of such research papers as follows, with the aim of suggesting new directions of investigation in the fields of enzyme research, protein engineering, and drug development.

THE INTERACTIONS OF VERTEBRATES AND INVERTEBRATES IN PEATLANDS AND MARSHES

1987 ◽  
Vol 119 (S140) ◽  
pp. 15-30 ◽  
Author(s):  
Henry R. Murkin ◽  
Bruce D.J. Batt
Keyword(s):  
Current Knowledge ◽  
Life Cycles ◽  
Future Research ◽  
Aquatic Environments ◽  
Research Needs ◽  
Avian Community ◽  
Wide Range ◽  
Dead Plant ◽  
Living Organisms ◽  
And Function

AbstractThis paper reviews the interactions of vertebrates and invertebrates in peatlands and marshes to assess current knowledge and future research needs. Living organisms may interact through a number of direct trophic and nutrient pathways and a variety of non-trophic, habitat-dependent relationships. Freshwater marshes and peatlands are dynamic aquatic environments and organisms that occupy these areas must be adapted to a wide range of environmental conditions. The avian community illustrates the main interactions of invertebrates and vertebrates in peatlands and marshes. Waterfowl, along with fish and furbearers, are the most economically important vertebrates using these habitats. Each of these groups has important trophic and habitat links to the invertebrates within wetlands.The most common interaction between vertebrates and invertebrates is the use of invertebrates as food by vertebrates. Few studies, however, have dealt with trophic dynamics or secondary production within wetlands. Waterfowl, fish, and many other wetland vertebrates, during all or part of their life cycles, regularly feed on invertebrates. Some invertebrates are vectors of disease and parasites to vertebrates. Vertebrates can directly affect the structural substrate that invertebrates depend on as habitat through consumption of macrophytes or through the use of living and dead plant material in the construction of houses and nests. Conversely, herbivorous invertebrates may directly affect the survival and distribution of macrophytes in wetlands. Macrophyte distribution, in turn, is an important factor in determining vertebrate use of wetlands. The general lack of both taxonomic and ecological information on invertebrates in wetlands is the main hindrance to future elucidation of vertebrate–invertebrate interactions in these environments. Development of invertebrate sampling techniques suitable for wetland habitats also is necessary. More specific research needs must be met to develop a better understanding of the structure and function of these dynamic systems.

scholarly journals Metabolism and Functions of Inositol Pyrophosphates: Insights Gained from the Application of Synthetic Analogues

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4515
Author(s):  
Stephen B. Shears ◽  
Huanchen Wang
Keyword(s):  
Chemical Synthesis ◽  
Molecular Level ◽  
Biological Information ◽  
Biological Processes ◽  
Synthetic Analogues ◽  
Metabolic Turnover ◽  
Important Group ◽  
Wide Range ◽  
Inositol Pyrophosphates ◽  
Low Levels

Inositol pyrophosphates (PP-InsPs) comprise an important group of intracellular, diffusible cellular signals that a wide range of biological processes throughout the yeast, plant, and animal kingdoms. It has been difficult to gain a molecular-level mechanistic understanding of the actions of these molecules, due to their highly phosphorylated nature, their low levels, and their rapid metabolic turnover. More recently, these obstacles to success are being surmounted by the chemical synthesis of a number of insightful PP-InsP analogs. This review will describe these analogs and will indicate the important chemical and biological information gained by using them.

scholarly journals Chemistry of Organophosphonate Scale Growth Inhibitors: 2. Structural Aspects of 2-Phosphonobutane-1,2,4-Tricarboxylic Acid Monohydrate (PBTC.H2O)

2005 ◽  
Vol 3 (3-4) ◽  
pp. 119-134 ◽  
Author(s):  
Konstantinos D. Demadis ◽  
Raphael G. Raptis ◽  
Peter Baran
Keyword(s):  
Molecular Level ◽  
Cooling Water ◽  
Magnesium Silicate ◽  
Cost Effective ◽  
Tricarboxylic Acid ◽  
Industrial Applications ◽  
Normal Range ◽  
Network Of Hydrogen Bonds ◽  
And Function ◽  
Structural Aspects

Industrial water systems often suffer from undesirable inorganic deposits, such as calcium carbonate, calcium phosphate(s), magnesium silicate, and others. Synthetic water additives such as phosphonates and phosphonocarboxylates are the most important and widely utilized scale inhibitors in a plethora of industrial applications. The design of efficient and cost-effective inhibitors, as well as the study of their structure and function at the molecular level are important areas of research. This study reports the crystal and molecular structure of PBTC (PBTC = 2-phosphonobutane-1,2,4-tricarboxylic acid), one of the most widely used scale inhibitors in the cooling water treatment industry. Triclinic PBTC monohydrate crystallizes in the P 1 space group with cell dimesions, a =7.671(1) Å, b = 8.680(1) Å, c = 9.886(1) Å, α = 65.518(2) deg, β = 71.683(2) deg, γ = 76.173(2) deg, V = 564.20(11) Å3, and Z = 2. Bond distances in the -PO3moiety are 1.4928(10) Å for the P=O double bond and 1.5294(10) Å and 1.5578(10) Å for the two -P-O(H) groups. P-C and C-O bond lengths fall in the normal range. A network of hydrogen bonds are formed between the water molecule of crystallization, the -P-OH and the -COOH groups.

scholarly journals Production and Purification of Endogenously Modified tRNA-Derived Small RNAs

2020 ◽  
Author(s):  
Aleksej Drino ◽  
Vera Oberbauer ◽  
Conor Troger ◽  
Eva Janisiw ◽  
Dorothea Anrather ◽  
...  
Keyword(s):  
Small Rnas ◽  
Molecular Level ◽  
Molecular Function ◽  
Biological Processes ◽  
Biological Impact ◽  
Rna Sequences ◽  
Preparative Scale ◽  
Transfer Rnas ◽  
Wide Range ◽  
Biological Sources

ABSTRACTDuring particular stress conditions, transfer RNAs (tRNAs) become substrates of stress-induced endonucleases, resulting in the production of distinct tRNA-derived small RNAs (tsRNAs). These small RNAs have been implicated in a wide range of biological processes, but how isoacceptor and even isodecoder-specific tsRNAs act at the molecular level is still poorly understood. Importantly, stress-induced tRNA cleavage affects only a few tRNAs of a given isoacceptor or isodecoder, raising the question as to how such limited molecule numbers could exert measurable biological impact. While the molecular function of individual tsRNAs is likely mediated through association with other molecules, addressing the interactome of specific tsRNAs has only been attempted by using synthetic RNA sequences. Since tRNAs carry post-transcriptional modifications, tsRNAs are likely modified but the extent of their modifications remains largely unknown. Here, we developed a biochemical framework for the production and purification of specific tsRNAs using human cells. Preparative scale purification of tsRNAs from biological sources should facilitate experimentally addressing as to how exactly these small RNAs mediate the multitude of reported molecular functions.

scholarly journals Twisted and frustrated states of matter

2012 ◽  
Vol 468 (2142) ◽  
pp. 1521-1542 ◽  
Author(s):  
John W. Goodby
Keyword(s):  
Molecular Level ◽  
Partial Ordering ◽  
Space Groups ◽  
Broken Symmetries ◽  
Nonlinear Properties ◽  
Information Displays ◽  
Wide Range ◽  
The World ◽  
Dynamical Fluctuations ◽  
Living Organisms

The World, and much of Nature that we see within it, experiences an environment of reduced symmetries. For example, living organisms are dependent on asymmetric or dissymmetric structures for their life processes. In the solid state, a large number of space groups are chiral. Conversely, in liquids, the effects of reduced symmetries are smeared out owing to the dynamical fluctuations of the constituent molecules, atoms or ions. Thus, on progressing from the strongly ordered solid to the amorphous liquid state, the effects of reduced symmetries weaken as the molecular or atomic correlations and penetration lengths fall. Between these two states of matter, the fourth state of organized fluids can be markedly affected by chirality, and over substantial length scales, owing to both the fluidity and partial ordering of the molecules. In effect, complex fluids can amplify the effects of chirality at the molecular level. Broken symmetries in self-organizing systems can lead to the formation of novel phases of matter and to the creation of structured liquids, and to the generation of nonlinear properties such as heli-, ferro-, ferri- and antiferro-electricity, and electroclinism, which can be harnessed in a wide range of applications including thermal sensors, imaging devices and information displays, to name but a few.

scholarly journals Nanotoxicity: Dimensional and Morphological Concerns

2011 ◽  
Vol 2011 ◽  
pp. 1-15 ◽  
Author(s):  
Mohmmad Younus Wani ◽  
Mohd Ali Hashim ◽  
Firdosa Nabi ◽  
Maqsood Ahmad Malik
Keyword(s):  
Molecular Level ◽  
Toxic Effects ◽  
New Materials ◽  
Safety Test ◽  
Wide Range ◽  
Different Types ◽  
Potential Applications ◽  
The Subject ◽  
Living Organisms ◽  
Different Sources

Nanotechnology deals with the construction of new materials, devices, and different technological systems with a wide range of potential applications at the atomic and molecular level. Nanomaterials have attracted great attention for numerous applications in chemical, biological, and industrial world because of their fascinating physicochemical properties. Nanomaterials and nanodevices are being produced intentionally, unintentionally, and manufactured or engineered by different methods and released into the environment without any safety test. Nantoxicity has become the subject of concern in nanoscience and nanotechnology because of the increasing toxic effects of nanomaterials on the living organisms. Nanomaterials can move freely as compared to the large-sized particles; therefore, they can be more toxic than bulky materials. This review article delineates the toxic effects of different types of nanomaterials on the living organisms through different sources, like water, air, contact with skin, and the methods of determinations of these toxic effects.

Microwaves: Application in Electron Microscopy

1990 ◽  
Vol 48 (3) ◽  
pp. 140-141
Author(s):  
Anthony S-Y Leong ◽  
David W Gove
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Chemical Reactions ◽  
Electromagnetic Waves ◽  
Tissue Fixation ◽  
Primary Method ◽  
Dipolar Molecules ◽  
Wide Range ◽  
Time Required ◽  
Cryostat Sections

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.

Chaperonin as the normal controls and pathological anti-stress response in the human reproductive system

2016 ◽  
pp. 126-129
Author(s):  
M. Makarenko ◽  
◽  
D. Hovsyeyev ◽  
L. Sydoryk ◽  
◽  
...  
Keyword(s):  
Reproductive System ◽  
Stress Proteins ◽  
Physiological Stress ◽  
Protein Complexes ◽  
Reproductive Function ◽  
Intercellular Signaling ◽  
Toll Like Receptors ◽  
Wide Range ◽  
Protein Functions ◽  
And Function

Different kinds of physiological stress cause mass changes in the cells, including the changes in the structure and function of the protein complexes and in separate molecules. The protein functions is determined by its folding (the spatial conclusion), which depends on the functioning of proteins of thermal shock- molecular chaperons (HSPs) or depends on the stress proteins, that are high-conservative; specialized proteins that are responsible for the correct proteinaceous folding. The family of the molecular chaperones/ chaperonins/ Hsp60 has a special place due to the its unique properties of activating the signaling cascades through the system of Toll-like receptors; it also stimulates the cells to produce anti- inflammatory cytokines, defensins, molecules of cell adhesion and the molecules of MHC; it functions as the intercellular signaling molecule. The pathological role of Hsp60 is established in a wide range of illnesses, from diabetes to atherosclerosis, where Hsp60 takes part in the regulation of both apoptosis and the autoimmune processes. The presence of the HSPs was found in different tissues that are related to the reproductive system. Key words: molecular chaperons (HSPs), Toll-like receptors, reproductive function, natural auto antibody.

Possession and Repetition

2012 ◽  
Vol 6 (1-3) ◽  
pp. 243-259 ◽  
Author(s):  
Yohan Yoo
Keyword(s):  
First Century ◽  
Daily Lives ◽  
Modern Times ◽  
Sacred Texts ◽  
New Methods ◽  
Wide Range ◽  
Lay Buddhists ◽  
Iconic Status ◽  
And Function ◽  
To Receive

This article demonstrates the need for the iconic status and function of Buddhist scripture to receive more attention by illuminating how lay Korean Buddhists try to appropriate the power of sutras. The oral and aural aspects of scripture, explained by Wilfred Cantwell Smith, provide only a limited understanding of the characteristics of scripture. It should be noted that, before modern times, most lay people, not only in Buddhist cultures but also in Christian and other traditions, neither had the chance to recite scriptures nor to listen to their recitations regularly. Several clear examples demonstrate contemporary Korean Buddhists’ acceptance of the iconic status of sutras and their attempt to appropriate the power and status of those sacred texts. In contemporary Korea, lay Buddhists try to claim the power of scriptures in their daily lives by repeating and possessing them. Twenty-first century lay believers who cannot read or recite in a traditional style have found new methods of repetition, such as internet programs for copying sacred texts and for playing recordings of their recitations. In addition, many Korean Buddhists consider the act of having sutras in one’s possession to be an effective way of accessing the sacred status and power of these texts. Hence, various ways of possessing them have been developed in a wide range of products, from fancy gilded sutras to sneakers embroidered with mantras.

Environmental significance of atrazine in aqueous systems and its removal by biological processes: an overview

2013 ◽  
Vol 8 (2) ◽  
pp. 159-178 ◽  
Keyword(s):  
Drinking Water ◽  
Ground Water ◽  
Water Environment ◽  
Biological Processes ◽  
Biological Degradation ◽  
Environmental Significance ◽  
Carbon And Nitrogen ◽  
Carbon Nitrogen Ratio ◽  
Nitrogen Ratio ◽  
Living Organisms

Atrazine, a chlorinated s-triazine group of herbicide is one of the most widely used pesticides in the World. Due to its extensive use, long half-life and various toxic properties, it has very high environmental significance. Up to 22 mg l-1 of atrazine was found in ground water whereas permissible limit of atrazine is in ppb level in drinking water. As per Indian standard there should not be any pesticide present in drinking water. Among many other treatment processes available, Incineration, adsorption, chemical treatment, phytoremediation and biodegradation are the most commonly used ones. Biological degradation of atrazine depends upon various factors like the operating environment, external carbon and nitrogen sources, carbon/ nitrogen ratio (C/N), water content and the bacterial strain. Although, general atrazine degradation pathways are available, the specific pathways in specific conditions are not yet clearly defined. In this paper extensive review has been made on the occurrence of atrazine in surface and ground water bodies, probable sources and causes of its occurrence in water environment, the toxicity of atrazine on various living organisms and its removal by biological processes.

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