scholarly journals The semisynthesis of analogues of cytochrome c. Modifications of arginine residues 38 and 91

1983 ◽  
Vol 215 (3) ◽  
pp. 651-658 ◽  
Author(s):  
C J A Wallace ◽  
K Rose
Keyword(s):  
Cytochrome C ◽  
Chemical Properties ◽  
Biological Properties ◽  
Adduct Formation ◽  
Eukaryotic Evolution ◽  
Functional Roles ◽  
Arginine Residues ◽  
Biological Tests ◽  
Horse Cytochrome ◽  
And Chemical Properties

The arginine residues at positions 38 and 91 of horse cytochrome c are absolutely conserved throughout eukaryotic evolution. For studies of the functional roles of these residues, we have prepared, by semisynthetic techniques, analogues of cytochrome c in which one or the other of the arginine residues has been modified. The products of modification by adduct formation with pentane-2,4-dione were purified and extensively characterized. In biological tests, the arginine-91-modified cytochrome c showed little difference in behaviour from native horse cytochrome c. Modification of arginine-38, however, led to extensive changes in biological and chemical properties. We also prepared and tested adducts with cyclohexane-1,2-dione and camphorquinone-10-sulphonic acid. The same effects on biological properties were noted irrespective of the nature of the modifying group. We suggest reasons for the differences in sensitivity of the two sites.

scholarly journals The effect of complete or specific partial acetimidylation on the biological properties of cytochrome c and cytochrome c-T

1984 ◽  
Vol 217 (3) ◽  
pp. 595-599 ◽  
Author(s):  
C J A Wallace
Keyword(s):  
Structural Change ◽  
Cytochrome C ◽  
Oxygen Uptake ◽  
Redox Potential ◽  
Biological Properties ◽  
Amino Groups ◽  
Cytochromes C ◽  
Restricted Region ◽  
Horse Cytochrome

The biological consequences of acetimidylation of all 19 epsilon-amino groups of horse cytochrome c are a slight decrease in both the redox potential of the protein and its ability to stimulate oxygen uptake in the cytochrome c-depleted-mitochondria assay. Examination of a number of specific partially acetimidylated analogues and acetimidylated cytochromes c of other species has shown that the changes in biological properties, which are associated with a slight structural change as monitored by n.m.r. spectroscopy [Boswell, Moore, Williams, Harris, Wallace, Bocieck & Welti (1983) Biochem. J. 213, 679-686], appear to stem from modification of residues in a restricted region of the sequence. The failure of the redox potential of Saccharomyces cerevisae cytochrome c to be affected by acetimidylation suggests that it is lysine-53, absent from that species, that is the sensitive residue.

scholarly journals Structure Determination of C23H19N4OBr from Synchrotron Data

2014 ◽  
Vol 70 (a1) ◽  
pp. C141-C141
Author(s):  
Ozen Ozgen ◽  
Engin Kendi ◽  
Semra Koyunoglu ◽  
Akgul Yesilada ◽  
Hwo-Shuenn Sheu
Keyword(s):  
Powder Diffraction ◽  
Structural Information ◽  
Chemical Properties ◽  
Biological Properties ◽  
Cell Parameters ◽  
Fundamental Understanding ◽  
Physical And Chemical ◽  
Radiation Research ◽  
And Chemical Properties

A significant part of medicine is based on the discovery and development of drugs. It is very important to know the crystal structure of pharmaceutical compounds for fundamental understanding of structure, physical and chemical properties. Many of these materials are available only as powders. So any structural information must be obtained from powder diffraction. I am going to present following the stages while solving the structure of C23H19N4OBr, 2-[3-phenyl-4(m-bromophenyl)-2-pyrazolin-1-yl]-3-methyl-4(3H)-quinazolinone, from 2-pyrazolines derivatives. The compounds are known to display various biological properties such as fungicidal insecticidal, anti bacterial, anti viral activities, pharmacological properties such as antiinflammatory agents and have industral properties(1). The powder diffraction data was collected with Debye Scherrer camera at the BL01C2 beamline at room temperature in National Synchrotron Radiation Research Center(NSRRC), Taiwan. X-ray of wavelength was 1.0333Å. This compound crystallizes in orthorhombic system space group P bca, Z=8, unit cell parameters of a=25.83(1)Å, b=15.55(5)Å, c=10.63(3)Å, and V=4266.0(10)Å3. Reliability factors were reached Rwp=0.075, Rp=0.053, RB=0.086 ve S=1.31 after Rietveld refinement.

scholarly journals Insight into Erythrina Lectins: Properties, Structure and Proposed Physiological Significance

2017 ◽  
Vol 5 (1) ◽  
pp. 57-71 ◽  
Author(s):  
Makarim Elfadil M. Osman ◽  
Emadeldin Hassan E. Konozy
Keyword(s):  
Biological Significance ◽  
Chemical Properties ◽  
Biological Properties ◽  
Physical And Chemical Properties ◽  
Vegetative Tissues ◽  
Isolation And Characterization ◽  
Coral Tree ◽  
Physical And Chemical ◽  
Insight Into ◽  
And Chemical Properties

The genus Erythrina, collectively known as “coral tree”, are pantropical plants, comprising of more than 112 species. Since the early 1980s, seven of these have been found to possess hemagglutinating activity, although not yet characterized. However, around two dozen galactose-binding lectins have been isolated and fully characterized with respect to their sugar specificity, glycoconjugates agglutination, dependence of activity on metal ions, primary and secondary structures and stability. Three lectins have been fully sequenced and the crystal structures of the two proteins have been solved with and without the haptenic sugar. Lectins isolation and characterization from most of these species usually originated from the seeds, although the proteins from other vegetative tissues have also been reported. The main objective of this review is to summarize the physicochemical and biological properties of the reported purified Erythrina lectins to date. Structural comparisons, based on available lectins sequences, are also made to relate the intrinsic physical and chemical properties of these proteins. Particular attention is also given to the proposed biological significance of the lectins from the genus Erythrina.

scholarly journals Role of Gasotransmitters in Oxidative Stresses, Neuroinflammation, and Neuronal Repair

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Ulfuara Shefa ◽  
Seung Geun Yeo ◽  
Min-Sik Kim ◽  
In Ok Song ◽  
Junyang Jung ◽  
...  
Keyword(s):  
Chemical Properties ◽  
The Body ◽  
Great Length ◽  
Physical And Chemical Properties ◽  
Functional Roles ◽  
Oxidative Stresses ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Neuronal Repair

To date, three main gasotransmitters, that is, hydrogen sulfide (H2S), carbon monoxide (CO), and nitric oxide (NO), have been discovered to play major bodily physiological roles. These gasotransmitters have multiple functional roles in the body including physiologic and pathologic functions with respect to the cellular or tissue quantities of these gases. Gasotransmitters were originally known to have only detrimental and noxious effects in the body but that notion has much changed with years; vast studies demonstrated that these gasotransmitters are precisely involved in the normal physiological functioning of the body. From neuromodulation, oxidative stress subjugation, and cardiovascular tone regulation to immunomodulation, these gases perform critical roles, which, should they deviate from the norm, can trigger the genesis of a number of neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The purpose of this review is to discuss at great length physical and chemical properties and physiological actions of H2S, NO, and CO as well as shedding light on recently researched molecular targets. We particularly put emphasis on the roles in neuronal inflammation and neurodegeneration and neuronal repair.

scholarly journals Effects of organic and mineral fertilisers on biological properties of soil under seminatural grassland

2008 ◽  
Vol 54 (No. 8) ◽  
pp. 329-335
Author(s):  
Ľ. Ondrášek ◽  
J. Čunderlík
Keyword(s):  
Farmyard Manure ◽  
Chemical Properties ◽  
Fulvic Acids ◽  
Biological Properties ◽  
N Mineralisation ◽  
Manure Application ◽  
Total N ◽  
Growing Seasons ◽  
Properties Of Soil ◽  
And Chemical Properties

Over 2004–2006, effects of mineral fertilisers (60 N + 30 P + 60 K kg/ha or 120 N + 30 P + 60 K kg/ha) and farmyard manure (12 or 24 t/ha) application on biological and chemical properties of soil were studied in seminatural grassland. The research trial was established at Radvaň site, central Slovakia (altitude 480 m, loamy to sandy-loamy Cambisol). These parameters were investigated during the growing seasons: CO<sub>2</sub> production, intensity of total N mineralisation (TMN), the rate of nitrification (NIT), total C content in microbial biomass (MB-C), C<sub>ox</sub>, N<sub>t</sub>, P, K, Mg and the humic acids to fulvic acids ratio (HA:FA). At the application of mineral fertilisers, the highest N rate significantly increased TMN and NIT, mainly in 2004 and 2005. The manure application showed the strongest effects on the biological parameters. The manure rate of 12 t/ha significantly increased the soil respiration in 2005 and 2006 as well as TMN and NIT throughout the research. The manure application increased also the soil pH, MB-C, N<sub>t</sub>, Mg, P and C<sub>ox</sub>.

Sol–Gel Coating of Hydroxyapatite on Zirconia Substrate

2021 ◽  
Vol 21 (8) ◽  
pp. 4169-4173
Author(s):  
Yu Hyeon Yun ◽  
Jong Kook Lee
Keyword(s):  
Calcium Phosphate ◽  
Layer Structure ◽  
Sol Gel ◽  
Chemical Properties ◽  
High Strength ◽  
Biological Properties ◽  
Coated Film ◽  
Biological Performance ◽  
And Chemical Properties

The zirconia used in dental implants requires excellent mechanical and chemical properties such as high strength, high biological performance, corrosion resistance, and phase stability. In this study, after we prepared a highly fluidized solution of calcium phosphate, we fabricated a hydroxyapatite (HA) coating layer on a zirconia substrate using the sol–gel method to enhance its biocompatibility and bone-bonding ability. We dipped the zirconia substrate into the calcium phosphate sol to obtain the HA-coated film, which was dried at room temperature. The phase change and microstructural evolution were examined while the coating dried and during heat treatment. The biological activity of the coated and as-received substrates was evaluated using an in vitro experiment and the results were compared. The HA-coated film showed a highly dense and uniform layer structure, while its physical and biological properties depended on the starting substrate, coating times, and processing conditions.

scholarly journals The Effects of Iron Rust on the Ageing of Woods and Their Derived Pulp Paper

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3483
Author(s):  
Wael A. A. Abo Elgat ◽  
Ayman S. Taha ◽  
Mohamed Z. M. Salem ◽  
Yahia G. D. Fares ◽  
Martin Böhm ◽  
...  
Keyword(s):  
Wood Species ◽  
Lignin Content ◽  
Chemical Properties ◽  
Biological Properties ◽  
Accelerated Ageing ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Fungal Activity ◽  
Pulp Paper ◽  
And Chemical Properties

The accelerated ageing of wood in terms of heating or iron rusting has a potential effect on the physio-mechanical, chemical and biological properties of wood. The effects of accelerated ageing on the mechanical, physical and fungal activity properties of some wood materials (Schinus terebinthifolius, Erythrina humeana, Tectona grandis, Pinus rigida and Juglans nigra) were studied after several cycles of heating and iron rusting. The fungal activity was assayed against the growth of Aspergillus terreus, Aspergillus niger, Fusarium culmorum and Stemphylium solani. In addition, the mechanical and optical properties of paper sheets produced from those wood pulps by means of Kraft cooking were evaluated. The mechanical and chemical properties of the studied wood species were affected significantly (p < 0.05) by the accelerated ageing, compared to control woods. With Fourier transform infrared (FTIR) spectroscopy, we detected an increase in the intensity of the spectra of the functional groups of cellulose in the heated samples, which indicates an increase in cellulose content and decrease in lignin content, compared to other chemical compounds. For pulp properties, woods treated by heating showed a decrease in the pulp yield. The highest significant values of tensile strength were observed in pulp paper produced from untreated, heated and iron-rusted P. rigida wood and they were 69.66, 65.66 and 68.33 N·m/g, respectively; we calculated the tear resistance from pulp paper of untreated P. rigida (8.68 mN·m2/g) and T. grandis (7.83 mN·m2/g) and rusted P. rigida (7.56 mN·m2/g) wood; we obtained the values of the burst strength of the pulp paper of untreated woods of P. rigida (8.19 kPa·m2/g) and T. grandis (7.49 kPa·m2/g), as well as the fold number of the pulp paper of untreated, heated and rusted woods from P. rigida, with values of 195.66, 186.33 and 185.66, respectively. After 14 days from the incubation, no fungal inhibition zones were observed. Accelerated ageing (heated or iron-rusted) produced significant effects on the mechanical and chemical properties of the studied wood species and affected the properties of the produced pulp paper.

scholarly journals Comprehensive analysis of chemical and biological problems associated with browning agents used in aquatic studies

2021 ◽  
Author(s):  
Kristin Scharnweber ◽  
Sari Peura ◽  
Katrin Attermeyer ◽  
Stefan Bertilsson ◽  
Lucas Bolender ◽  
...  
Keyword(s):  
Organic Matter ◽  
Experimental Studies ◽  
Chemical Properties ◽  
Biological Properties ◽  
Zooplankton Abundance ◽  
Strong Impact ◽  
Biological Impacts ◽  
Ro Concentrate ◽  
Global Carbon ◽  
And Chemical Properties

Inland waters receive and process large amounts of colored organic matter from the terrestrial surroundings. These inputs dramatically affect the chemical, physical, and biological properties of water bodies, as well as their roles as global carbon sinks and sources. To understand the complex changes associated with allochthonous inputs, experiments are needed. However, manipulative studies, especially at ecosystem scales, require large amounts of dissolved organic matter with optical and chemical properties resembling indigenous organic matter. Here we compared the chemical and biological impacts of two leonardite products (HuminFeed (HF) and SuperHume (SH)) and a freshly derived reverse osmosis concentrate of organic matter (RO) in a set of comprehensive mesocosm- and laboratory-scale experiments and analyses. The chemical properties of RO concentrate and the leonardite products were very different with leonardite products being low and RO being high in carboxylic functional groups. Light had a strong impact on the properties of leonardite products, including loss of color and increased particle formation. Furthermore, HF had drastic impacts on bacteria as light stimulated bacterial production and modified community composition, while dark conditions appeared to inhibit bacterial processes. While none of the browning agents inhibited the growth of the tested phytoplankton, Gonyostomum semen, leonardite products had detrimental effects on zooplankton abundance and Daphnia reproduction. We conclude that the effects of browning agents extracted from leonardite are in sharp contrast to those originating from terrestrially-derived DOM. Hence, they should be used with great caution in experimental studies on the consequences of terrestrial carbon for aquatic systems.

Role of enzymes in soil

2018 ◽  
Vol 22 (03) ◽  
pp. 96-102 ◽  
Author(s):  
Bayarmaa J ◽  
Purev D
Keyword(s):  
Soil Enzymes ◽  
Great Influence ◽  
Chemical Properties ◽  
Biological Properties ◽  
Factors Affecting ◽  
Physical Chemical ◽  
Almost All ◽  
Physical And Chemical ◽  
And Chemical Properties

Enzymes are an integral part of the soil and their activity is closely related to the physical, chemical and biological properties of the soil. Human activities, intensive agriculture, changes in ecosystem, environmental pollution have a great influence on the activity of soil enzymes. Depending on the origin soil enzymes are indicators for accessing the condition of the soil for short and long period of time. Almost all anthropogenic and environmental factors affecting the physical and chemical properties of the soil are studied for this purpose, but enzymes in the soil are the most sensitive to these changes. So it is a time to the study of the enzymes in the soil.

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