A Study of the Conformational Properties of Glucagon in the Presence of Glycols

1974 ◽  
Vol 52 (6) ◽  
pp. 456-468 ◽  
Author(s):  
C. C. Contaxis ◽  
R. M. Epand
Keyword(s):  
Biological Activity ◽  
Tertiary Structure ◽  
Structural Response ◽  
Spectroscopic Properties ◽  
The Other ◽  
Monomeric Form ◽  
Conformational Properties ◽  
Α Helix

Elimination of the polymerization of glucagon has been achieved in the presence of glycols. The monomeric form of glucagon, found to be exclusively present under these conditions, is studied for its structural response to changes in the hydrophobicity of the environment. A reversible folding of the α-helix from about 0 to 80% is found to occur and it is suggested to proceed in two sequentially formed helical segments. Changes in the other spectroscopic properties are interpreted as changes in the tertiary structure. Implications for the biological activity are discussed.

scholarly journals The acetylation of insulin

1971 ◽  
Vol 121 (5) ◽  
pp. 737-745 ◽  
Author(s):  
D. G. Lindsay ◽  
S. Shall
Keyword(s):  
Biological Activity ◽  
Free Amino ◽  
Tertiary Structure ◽  
Group Analysis ◽  
Insulin Antibodies ◽  
The Other ◽  
Amino Group ◽  
Amino Groups ◽  
Chloromethyl Ketone ◽  
End Group

The acetylation of the free amino groups of insulin was studied by reaction of the hormone with N-hydroxysuccinimide acetate at pH6.9 and 8.5. The products formed were separated by chromatography on DEAE-Sephadex and were characterized by isoelectric focusing, by end-group analysis, by the incorporation of [3H]acetyl groups in the molecule, and by treatment with trypsin that had been treated with 1-chloro-4-phenyl-3-toluene-p-sulphonamidobutan-2-one (‘tosylphenylalanyl chloromethyl ketone’). Three monosubstituted products, two disubstituted products and one trisubstituted derivative were prepared. The α-amino groups of the terminal residues and the ∈-amino group of the lysine-B29 were the sites of reaction. Acetylation of any of the free amino groups did not affect the biological activity of insulin. It was demonstrated, however, that substitution at the glycine-A1 amino group by the larger residues, acetoacetyl or thiazolidinecarbonyl, produced a decrease in biological activity. Modification of the lysine-B29 or phenylalanine-B1 amino groups with these larger reagents did not affect the biological activity. Modification of the phenylalanine-B1 amino group by any of the three substituents resulted in a large decrease in the affinity of insulin for anti-insulin antibodies raised in the guinea pig. Modification of the other two amino groups did not affect the reaction with antibody. These observations are correlated with the tertiary structure of insulin.

A FACILE SYNTHESIS AND REACTIONS OF AMINO SELENOLO[2,3-b]PYRIDINE CARBOXYLATE

2015 ◽  
Vol 12 (1) ◽  
pp. 3910-3918 ◽  
Author(s):  
Dr Remon M Zaki ◽  
Prof Adel M. Kamal El-Dean ◽  
Dr Nermin A Marzouk ◽  
Prof Jehan A Micky ◽  
Mrs Rasha H Ahmed
Keyword(s):  
Biological Activity ◽  
Carbonyl Compounds ◽  
Mass Spectra ◽  
The Other ◽  
Pyridine Derivatives ◽  
Facile Synthesis ◽  
High Biological Activity ◽  
Basic Hydrolysis ◽  
Pyridine Carboxylate ◽  
Hydrolysis Of

 Incorporating selenium metal bonded to the pyridine nucleus was achieved by the reaction of selenium metal with 2-chloropyridine carbonitrile 1 in the presence of sodium borohydride as reducing agent. The resulting non isolated selanyl sodium salt was subjected to react with various α-halogenated carbonyl compounds to afford the selenyl pyridine derivatives 3a-f  which compounds 3a-d underwent Thorpe-Ziegler cyclization to give 1-amino-2-substitutedselenolo[2,3-b]pyridine compounds 4a-d, while the other compounds 3e,f failed to be cyclized. Basic hydrolysis of amino selenolo[2,3-b]pyridine carboxylate 4a followed by decarboxylation furnished the corresponding amino selenolopyridine compound 6 which was used as a versatile precursor for synthesis of other heterocyclic compound 7-16. All the newly synthesized compounds were established by elemental and spectral analysis (IR, 1H NMR) in addition to mass spectra for some of them hoping these compounds afforded high biological activity.

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel
Keyword(s):  
Biological Activity ◽  
Bacterial Growth ◽  
Xanthomonas Campestris ◽  
Plant Pathogens ◽  
Genetically Engineered ◽  
The Other ◽  
Computer Assisted ◽  
Signal Molecules ◽  
Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

scholarly journals Contribution of the CK2 Catalytic Isoforms α and α’ to the Glycolytic Phenotype of Tumor Cells

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 181
Author(s):  
Francesca Zonta ◽  
Christian Borgo ◽  
Camila Paz Quezada Meza ◽  
Ionica Masgras ◽  
Andrea Rasola ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Protein Kinase ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Therapeutic Strategies ◽  
The Other ◽  
Osteosarcoma Cell ◽  
Monomeric Form ◽  
New Information

CK2 is a Ser/Thr protein kinase overexpressed in many cancers. It is usually present in cells as a tetrameric enzyme, composed of two catalytic (α or α’) and two regulatory (β) subunits, but it is active also in its monomeric form, and the specific role of the different isoforms is largely unknown. CK2 phosphorylates several substrates related to the uncontrolled proliferation, motility, and survival of cancer cells. As a consequence, tumor cells are addicted to CK2, relying on its activity more than healthy cells for their life, and exploiting it for developing multiple oncological hallmarks. However, little is known about CK2 contribution to the metabolic rewiring of cancer cells. With this study we aimed at shedding some light on it, especially focusing on the CK2 role in the glycolytic onco-phenotype. By analyzing neuroblastoma and osteosarcoma cell lines depleted of either one (α) or the other (α’) CK2 catalytic subunit, we also aimed at disclosing possible pro-tumor functions which are specific of a CK2 isoform. Our results suggest that both CK2 α and α’ contribute to cell proliferation, survival and tumorigenicity. The analyzed metabolic features disclosed a role of CK2 in tumor metabolism, and suggest prominent functions for CK2 α isoform. Results were also confirmed by CK2 pharmacological inhibition. Overall, our study provides new information on the mechanism of cancer cells addiction to CK2 and on its isoform-specific functions, with fundamental implications for improving future therapeutic strategies based on CK2 targeting.

scholarly journals Isolasi dan Identifikasi Senyawa Fenolik dari Kulit Akar Tumbuhan Artocarpus Dadah Miq 63-74

2015 ◽  
Vol 4 (2) ◽  
pp. 205
Author(s):  
Indarto Indarto
Keyword(s):  
Biological Activity ◽  
Phenolic Compounds ◽  
Ir Spectroscopy ◽  
The Other ◽  
Flash Chromatography ◽  
Rare Plant ◽  
Isolation And Purification ◽  
Phenolic Group ◽  
The Village ◽  
Murine Leukemia

Artocarpus plant  dadah  Miq.  is one of the species of Artocarpus of the Moraceae family that belongs to a rare plant in nature. This plant is known as the main source of phenolic derivative compound that is flavone compound  in  or  tri-oxygenated and terisoprenilasi in C-3 position ,  and also known as the main source of phenolic compound derived flavonoids, aryl-benzofuran, stilbenoid and xanthane flavonoida, which have biological activity as promoters antitumor, antibacterial, antifungal, antiimflamatori, antikanker and others. This study aimed to isolate and identify the phenolic compounds contained in plant  A .  dadah obtained from the village of Purwoasri, North Metro District, Metro City, Lampung Province. Research stages include collection and sample preparation and extraction, isolation, and purification of compounds using KCV method, flash chromatography  , KKG, and TLC, while the identification of compounds is performed using ultraviolet-visible (UV-VIS) and infrared (IR) spectroscopy. In the present study, three compounds were isolated, one of which was estimated to be flavonoid compounds based on UV-VIS and IR spectra data which also had high activity against murine leukemia P-388 cells with IC 50  3.1 μg / mL. Based on the IR spectral data for the other two compounds there is a -OH uptake in the region of 3200-3500 cm -1, C = C aromatic uptake in the area of 1600-1400 cm -1 , so it is estimated that both compounds are phenolic group compounds.Tumbuhan Artocarpus dadah Miq.merupakan salah satu spesies Artocarpus dari famili Moraceae yang termasuk tumbuhan langka di alam. Tumbuhan ini dikenal sebagai sumber utama senyawa turunan fenolik yaitu senyawa flavon di atau tri-oksigenasi dan terisoprenilasi pada posisi C-3, dan juga dikenal sebagai sumber utama senyawa fenolik turunan flavonoid, aril-benzofuran, stilbenoid dan santon turunan flavonoida, yang memiliki aktivitas biologi sebagai promotor antitumor, antibakteri, antifungal, antiimflamatori, antikanker dan lain-lain.Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa fenolik yang terkandung dalam tumbuhan A. dadah yang diperoleh dari desa Purwoasri, Kecamatan Metro Utara, Kota Metro, Provinsi Lampung.Tahapan penelitian yang dilakukan meliputi pengumpulan dan persiapan sampel kemudian ekstraksi, isolasi, dan pemurnian senyawa menggunakan metode KCV, kromatografi flash, KKG, dan KLT, sedangkan identifikasi senyawa dilakukan menggunakan spektroskopi ultraungu-tampak (UV-VIS) dan inframerah (IR). Pada penelitian ini telah berhasil diisolasi tiga senyawa, yang salah satunya diperkirakan senyawa flavonoid berdasarkan data spektrum UV-VIS dan IR yang juga memiliki aktivitas tinggi terhadap sel murine leukemia P-388 dengan IC50 3,1 μg/mL. Berdasarkan data spektrum IR untuk dua senyawa yang lain terdapat serapan –OH pada daerah 3200-3500 cm-1, serapan C=C aromatik di daerah 1600-1400 cm-1, sehingga diperkirakan kedua senyawa tersebut merupakan senyawa golongan fenolik.

Fabrication and Characterisation of Reverse Proton Exchange Optical Waveguides in Neodymium Doped Lithium Niobate Crystals

2005 ◽  
Vol 480-481 ◽  
pp. 429-436
Author(s):  
M. Domenech ◽  
G. Lifante ◽  
F. Cussó ◽  
A. Parisi ◽  
A.C. Cino ◽  
...  
Keyword(s):  
Lithium Niobate ◽  
Optical Waveguides ◽  
Spectroscopic Properties ◽  
Proton Exchange ◽  
Fabrication Process ◽  
The Other ◽  
Ion Plating ◽  
Other Hand ◽  
Channel Waveguides ◽  
Lithium Niobate Crystals

In this work, the complete fabrication process which combines Proton Exchange (PE) and Reverse Proton Exchange (RPE) in Neodymium doped LiNbO3 channel waveguides is reported. To produce the PE-RPE channel waveguides the fabrication of dielectric SiO2 masks had to be implemented. For this propose, we adopted a technique based on the Ion Plating Plasma Assisted Deposition of SiO2 followed by the standard ultraviolet photolithographic patterning. On the other hand, we determined the main optical and spectroscopic properties of Nd3+ ions in the channel waveguides including the study of the lifetime as function as the polarisation.

Thyroxine, liothyronine and thyroid BP

1964 ◽  
Vol 2 (6) ◽  
pp. 21-22
Keyword(s):  
Biological Activity ◽  
The Other ◽  
Pure Substance ◽  
British Pharmacopoeia ◽  
Chemical Assay

L-thyroxine (Eltroxin - Glaxo; and others), liothyronine (Tertroxin - Glaxo; and others), a mixture of l-thyroxine and l-triiodothyronine (Diotroxin - Glaxo) and dried thyroid (Thyroid BP) are all used in the management of hypothyroidism. Large quantities of Thyroid BP are unfortunately still prescribed, probably not all for the treatment of demonstrable hypothyroidism. Unlike the other preparations, it is not a pure substance and needs to be assayed biologically. Chemical assay which is required by the British Pharmacopoeia does not reflect comparable biological activity.

scholarly journals Increase of 4-Hydroxybenzoic, a Bioactive Phenolic Compound, after an Organic Intervention Diet

Antioxidants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 340
Author(s):  
Sara Hurtado-Barroso ◽  
Paola Quifer-Rada ◽  
María Marhuenda-Muñoz ◽  
Jose Fernando Rinaldi de Alvarenga ◽  
Anna Tresserra-Rimbau ◽  
...  
Keyword(s):  
Biological Activity ◽  
Healthy Subjects ◽  
The Other ◽  
Hydroxybenzoic Acid ◽  
Period Analysis ◽  
Randomized Controlled ◽  
Organic Products ◽  
Phenolic Metabolite ◽  
Health Promoting ◽  
Conventional Foods

Consumption of organic products is increasing yearly due to perceived health-promoting qualities. Several studies have shown higher amounts of phytochemicals such as polyphenols and carotenoids in foods produced by this type of agriculture than in conventional foods, but whether this increase has an impact on humans still needs to be assessed. A randomized, controlled and crossover study was carried out in nineteen healthy subjects aged 18–40 years, who all followed an organic and conventional healthy diet, both for a 4-week period. Analysis of biological samples revealed a significant increase on the excretion of 4-hydroxybenzoic acid (4-HBA), a phenolic metabolite with biological activity, after the organic intervention. However, no changes were observed in the other variables analyzed.

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