scholarly journals Thermophilic Enzymes

2021 ◽  
Vol 7 (3) ◽  
pp. 13-23
Author(s):  
Matilde Viegas ◽  
Maria João Ramos ◽  
Pedro Alexandrino Fernandes
Keyword(s):  
Hydrogen Bonds ◽  
Industrial Production ◽  
Tertiary Structure ◽  
Ion Pairs ◽  
Industrial Processes ◽  
Thermophilic Enzymes ◽  
Network Of Hydrogen Bonds ◽  
Unlimited Access ◽  
Food Commodities ◽  
Access To Food

Substantial improvements in the industrial production of goods led to a widespread feeling of unlimited access to food, commodities, and energy. As greener alternatives for industrial processes are in demand, scientists have turned to enzymes, looking for apt biocatalysts. Focusing on extremophiles, this mini review draws a comparison between thermophiles and their mesophilic counterparts, exploring what features are instrumental to their thermostability. A higher number of ion-pairs, hydrophobicity of buried side chains, compact tertiary structure cores, and a complex network of hydrogen bonds are the four main characteristics responsible for the robustness of thermophilic enzymes.

scholarly journals PSI-20 Public perceptions of problematic equine industry sectors and management scenarios

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 263-264
Author(s):  
Kelly Melvin ◽  
Jennie L Ivey ◽  
Liesel G Schneider ◽  
Peter Krawczel
Keyword(s):  
Management Practices ◽  
Multinomial Logistic Regression ◽  
Management Scenarios ◽  
The Public ◽  
Management Scenario ◽  
Unlimited Access ◽  
Horse Industry ◽  
Definition Of ◽  
Access To Food ◽  
Equine Industry

Abstract The equine industry is highly variable with many different sectors and management practices. To determine how the public views common management practices and discipline-specific areas of the equine industry, an online study was distributed via email and social media over a 6-week period to U.S. residents over the age of 18 (n = 1,372). Survey questions included demographics, industry connection, definition of welfare and equine classification. Respondents were asked to select the most concerning option from a series of management-related scenarios. The production livestock and equine industries were then segmented by species or discipline, respectively, and respondents were asked which sector was most problematic. To analyze the data, frequency tables (Proc FREQ) and multinomial logistic regression (Proc LOGISTIC) were used in SAS 9.4 (Cary, NC) to test the factors associated with likelihood to select a given management scenario from each series (α=0.05). Respondents who were heavily connected to the industry were four times more likely than lightly connected individuals to select that a blanketed horse or unblanketed horse in 30°F weather with unlimited access to food and water equally presented no concern than to say that a blanketed or unblanketed horse in 30°F weather with unlimited access to food and water and were concerning (OR= 4.09; 95%CL: 2.08,8.04). Of the 1,244 respondents who answered, 563 (45%) said that the gaited horse industry is the most problematic equine industry compared to the racing industry (41%) and stock horse industry (8.7%). Understanding how the public perceives the various animal industries and management scenarios in relation to an individual’s connection to the industry, classification of equines and welfare definition is important to assess and improve educational intervention strategies.

4-(Piperidin-1-yl)pyridinium hexafluorophosphate at 150 K

2003 ◽  
Vol 59 (11) ◽  
pp. o622-o624 ◽  
Author(s):  
Bruce D. James ◽  
Siti Mutrofin ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Hydrogen Bonds ◽  
Structural Characterization ◽  
Title Compound ◽  
Ion Pairs ◽  
Piperidine Ring ◽  
Torsion Angles ◽  
Compound C ◽  
Counter Ions

Structural characterization of the title compound, C10H15N2 +·PF6 −, shows it to be ionic, with the pyridine rather than the piperidine N atom being protonated and forming hydrogen bonds to the counter-ions, resulting in two independent ion pairs. A number of unusual features are noted, in particular the remarkably close inter-ring hydrogen contacts [1.97 (3)–2.00 (3) Å] and the considerable differences in the pair of cations, in respect of the torsion angles within the piperidine ring involving the bonds to either side of the N atom.

scholarly journals Modification of Chitin Particles with Ionic Liquids Containing Ethyl Substituent in a Cation

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Malgorzata M. Jaworska ◽  
Andrzej Górak ◽  
Joanna Zdunek
Keyword(s):  
Particle Size ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Hydrogen Bonds ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
High Viscosity ◽  
Physical Structure ◽  
Ethyl Group ◽  
Network Of Hydrogen Bonds

Chitin cannot be dissolved in conventional solvents due to the strong inter- and intrasheet network of hydrogen bonds and the large number of crystalline regions. Some ionic liquids (ILs) have been suggested in the literature as possible solvents for chitin. Seven of them, all having an ethyl group as substituent in the cationic ring, have been tested in this work: [Emim][Cl], [Emim][Br], [Emim][I], [Emim][OAc], [Emim][Lact], [Epyr][I], and [EMS][BFSI]. Chitin was insoluble in [EMS][BFSI] while for all other ILs solubility was limited due to high viscosity of solutions and equilibria have not been reached. Changes in physical structure, particle size distribution, and crystallinity of recovered chitin depended on ionic liquid used. Increase in porosity was observed for chitin treated with [Emim][Cl], [Emim][I], [Emim][Br], and [Emim][Lact]; changes in particle size distribution were observed for [Emim][AcOH] and [EMS][BFSI]; increase in crystallinity was noticed for chitin treated with [Epyr][I] while decrease in crystallinity for [Emim][I] was noticed. All tested ionic liquids were reused four times and changes in FTIR spectra could be observed for each IL.

Biotransformation, spectroscopic investigation, crystal structure and electrostatic properties of 3,7α-dihydroxyestra-1,3,5(10)-trien-17-one monohydrate studied using transferred electron-density parameters

2018 ◽  
Vol 74 (5) ◽  
pp. 534-541 ◽  
Author(s):  
Ammara Shahid ◽  
Ambreen Aziz ◽  
Sajida Noureen ◽  
Maqsood Ahmed ◽  
Sammer Yousuf ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Electron Density ◽  
Van Der Waals Interactions ◽  
Estradiol Valerate ◽  
Spectrometric Analysis ◽  
Spectroscopic Techniques ◽  
Charge Delocalization ◽  
Atom Model ◽  
Network Of Hydrogen Bonds

The biologically transformed product of estradiol valerate, namely 3,7α-dihydroxyestra-1,3,5(10)-trien-17-one monohydrate, C18H22O3·H2O, has been investigated using UV–Vis, IR, 1H and 13C NMR spectroscopic techniques, as well as by mass spectrometric analysis. Its crystal structure was determined using single-crystal X-ray diffraction based on data collected at 100 K. The structure was refined using the independent atom model (IAM) and the transferred electron-density parameters from the ELMAM2 database. The structure is stabilized by a network of hydrogen bonds and van der Waals interactions. The topology of the hydrogen bonds has been analyzed by the Bader theory of `Atoms in Molecules' framework. The molecular electrostatic potential for the transferred multipolar atom model reveals an asymmetric character of the charge distribution across the molecule due to a substantial charge delocalization within the molecule. The molecular dipole moment was also calculated, which shows that the molecule has a strongly polar character.

scholarly journals 2-Amino-4-methylpyridinium 4-methoxybenzoate dihydrate

IUCrData ◽  
2017 ◽  
Vol 2 (5) ◽  
Author(s):  
P. Sivakumar ◽  
G. Ezhamani ◽  
S. Israel ◽  
G. Chakkaravarthi
Keyword(s):  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Ion Pairs ◽  
Three Dimensional ◽  
Water Molecules ◽  
Π Stacking ◽  
Dimensional Network ◽  
Centroid Distance ◽  
Molecular Salt

In the title hydrated molecular salt, C6H9N2+·C8H7O3−·2H2O, the cation is protonated at the pyridine N atom. The cation and anion are linked by a pair of N—H...O hydrogen bonds, which generates anR22(8) loop, and the dihedral angle between their ring planes is 16.07 (14)°. The ion pairs are linked by O—H...O hydrogen bonds involving the water molecules, generating a three-dimensional network. Weak C—H...O and aromatic π–π stacking [centroid-to-centroid distance = 3.5874 (17) Å] interactions are also observed.

scholarly journals 3,3′-(Dodecane-1,12-diyl)bis(1-methylimidazolium) 5,5′-azotetrazolate heptahydrate

IUCrData ◽  
2017 ◽  
Vol 2 (9) ◽  
Author(s):  
Gerhard Laus ◽  
Klaus Wurst ◽  
Herwig Schottenberger
Keyword(s):  
Hydrogen Bonds ◽  
Title Compound ◽  
Water Molecules ◽  
Compound C ◽  
Network Of Hydrogen Bonds

The title compound, C20H36N4·C2N10·7H2O, was obtained by reaction of 1-methylimidazole with 1,12-dibromododecane, followed by repeated ion metathesis (bromide → sulfate → azotetrazolate). An intricate network of hydrogen bonds is formed between anions and water molecules, leading to a layered arrangement parallel to (101).

scholarly journals (μ-Dihydrogen pyrazine-2,3,5,6-tetracarboxylato-κ6O2,N1,O6;O3,N4,O5)bis(diaqualithium) monohydrate

2014 ◽  
Vol 70 (5) ◽  
pp. m172-m172 ◽  
Author(s):  
Wojciech Starosta ◽  
Janusz Leciejewicz
Keyword(s):  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Water Molecules ◽  
Crystal Water ◽  
Rotation Axes ◽  
Trigonal Bipyramidal ◽  
Carboxylate Groups ◽  
Distorted Trigonal Bipyramidal Coordination ◽  
Network Of Hydrogen Bonds ◽  
Distorted Trigonal Bipyramidal

The structure of the title compound, [Li2(C8H2N2O8)(H2O)4]·H2O, is composed of dinuclear molecules in which the ligand bridges two symmetry-related LiIions, each coordinated also by two water O atoms, in anO,N,O′-manner. The Li and N atoms occupy special positions on twofold rotation axes, whereas a crystal water molecule is located at the intersection of three twofold rotation axes. The LiIcation shows a distorted trigonal–bipyramidal coordination. Two carboxylate groups remain protonated and form short interligand hydrogen bonds. The molecules are held together by a network of hydrogen bonds in which the coordinating and solvation water molecules act as donors and carboxylate O atoms as acceptors, forming a three-dimensional architecture.

(R)-1-Phenylethanaminium–(S,S)-2,3-dibromosuccinate–(R,R)-2,3-dibromosuccinic acid–water (2/1/1/2)

2006 ◽  
Vol 62 (4) ◽  
pp. o1281-o1283
Author(s):  
Andreas Fischer
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Quantitative Yield ◽  
Acid Water ◽  
Two Dimensional ◽  
Rotation Axes ◽  
Compound C ◽  
Dimensional Network ◽  
Network Of Hydrogen Bonds

From an aqueous solution of racemic 2,3-dibromosuccinic acid and (R)-1-phenylethanamine, crystals of the title compound, C8H12N+·0.5C4H2Br2O4 2−·0.5C4H4Br2O4·H2O, were obtained in almost quantitative yield. The structure contains both enantiomers of the starting material, dibromosuccinic acid. The S,S enantiomer is present as a dianion and the R,R enantiomer as the neutral acid; both of these components lie on twofold rotation axes. The structure features a complex two-dimensional network of hydrogen bonds.

Sign in / Sign up

Export Citation Format

Share Document