scholarly journals Iron-Binding and Anti-Fenton Properties of Novel Amino Acid-Derived Cyclic Imide Dioximes

Antioxidants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 473 ◽  
Author(s):  
Janez Mravljak ◽  
Žiga Jakopin
Keyword(s):  
Molecular Structure ◽  
Amino Acid ◽  
Antioxidant Properties ◽  
Binding Motif ◽  
Iron Binding ◽  
Iron Cycling ◽  
Cyclic Imide ◽  
Structural Requirements ◽  
Chelating Ability ◽  
Potential Use

We present a novel route for the preparation of amino acid-derived cyclic imide dioxime derivatives. Readily accessible amino acids were conveniently converted to their corresponding cyclic imide dioximes in simple synthetic steps. The aim of this work was to describe and compare the iron-chelating and antioxidant properties of synthesized compounds in relation to their molecular structure, and in particular, which of those features are essential for iron(II)-chelating ability. The glutarimide dioxime moiety has been established as an iron(II)-binding motif and imparts potent anti-Fenton properties to the compounds. Compound 3 was shown to strongly suppress hydroxyl radical formation by preventing iron cycling via Fe-complexation. These findings provide insights into the structural requirements for achieving anti-Fenton activity and highlight the potential use of glutarimide dioximes as antioxidants.

ASSESSEMENTOF AMINO ACID, VITAMIN, FUNCTIONAL AND ANTIOXIDANT PROPERTIES IN A LEGUME-CEREAL BASED COMPLEMENTARY BLEND

2020 ◽  
Vol 8 (4) ◽  
pp. 1038-1049
Author(s):  
Rougbo Ndjomon Paterne ◽  
◽  
Sea Tehi Bernard ◽  
Doue Ginette Gladys ◽  
◽  
...  
Keyword(s):  
Amino Acid ◽  
Antioxidant Properties

Streptococcus salivarius Isolates of Varying Acid Tolerance Exhibit F1F0-ATPase Conservation

2021 ◽  
pp. 1-4
Author(s):  
Lauren L. Allen ◽  
Nicholas C.K. Heng ◽  
Geoffrey R. Tompkins
Keyword(s):  
Molecular Structure ◽  
Amino Acid ◽  
Acid Tolerance ◽  
Mutans Streptococci ◽  
Streptococcus Salivarius ◽  
Synonymous Substitutions ◽  
Carious Lesions ◽  
Genes Encoding ◽  
Atpase Subunits ◽  
Membrane Bound

Genes encoding the subunits of the membrane-bound F<sub>1</sub>F<sub>0</sub>-ATPase (responsible for exporting protons from the cytoplasm and contributing to acid tolerance) were sequenced for 24 non-mutans streptococci isolated from carious lesions. Isolates, mostly <i>Streptococcus salivarius</i>, displayed a continuum of acid tolerance thresholds ranging from pH 4.55 to 3.39, but amino acid alignments of F<sub>1</sub>F<sub>0</sub>-ATPase subunits revealed few non-synonymous substitutions and these were unrelated to acid tolerance. Thus, the F<sub>1</sub>F<sub>0</sub>-ATPase is highly-conserved among <i>S. salivarius</i> isolates despite varying acid tolerance thresholds, supporting the contention that acid tolerance is determined by the level of gene/protein expression rather than variation in molecular structure.

scholarly journals Evaluation of Antioxidant Properties ofPhaulopsis fascisepalaC.B.Cl. (Acanthaceae)

2009 ◽  
Vol 6 (2) ◽  
pp. 227-231 ◽  
Author(s):  
S. A. Adesegun ◽  
A. Fajana ◽  
C. I. Orabueze ◽  
H. A. B. Coker
Keyword(s):  
Ascorbic Acid ◽  
Leaf Extract ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Total Phenolic ◽  
Chelating Ability

The antioxidant activities of crude extract ofPhaulopsis fascisepalaleaf were evaluated and compared with α-tocopherol and BHT as synthetic antioxidants and ascorbic acid as natural-based antioxidant.In vitro, we studied its antioxidative activities, radical-scavenging effects, Fe2+-chelating ability and reducing power. The total phenolic content was determined and expressed in gallic acid equivalent. The extract showed variable activities in all of thesein vitrotests. The antioxidant effect ofP. fascisepalawas strongly dose dependent, increased with increasing leaf extract dose and then leveled off with further increase in extract dose. Compared to other antioxidants used in the study, α-Tocopherol, ascorbic acid and BHT,P. fascisepalaleaf extract showed less scavenging effect on α,α,-diphenyl-β-picrylhydrazyl (DPPH) radical and less reducing power on Fe3+/ferricyanide complex but better Fe2+-chelating ability. These results revealed thein vitroantioxidant activity ofP.fascisepala.Further investigations are necessary to verify these activitiesin vivo.

scholarly journals Physicochemical and Antioxidant Properties of Acid- and Pepsin-Soluble Collagens from the Scales of Miiuy Croaker (Miichthys Miiuy)

Marine Drugs ◽  
2018 ◽  
Vol 16 (10) ◽  
pp. 394 ◽  
Author(s):  
Long-Yan Li ◽  
Yu-Qin Zhao ◽  
Yu He ◽  
Chang-Feng Chi ◽  
Bin Wang
Keyword(s):  
Amino Acid ◽  
Hydroxyl Radical ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Antioxidant Properties ◽  
Superoxide Anion Radical ◽  
Type I ◽  
Dpph Radical ◽  
Soluble Collagen ◽  
Miichthys Miiuy

In this report, acid-soluble collagen (ASC-MC) and pepsin-soluble collagen (PSC-MC) were extracted from the scales of miiuy croaker (Miichthys miiuy) with yields of 0.64 ± 0.07% and 3.87 ± 0.15% of dry weight basis, respectively. ASC-MC and PSC-MC had glycine as the major amino acid with the contents of 341.8 ± 4.2 and 344.5 ± 3.2 residues/1000 residues, respectively. ASC-MC and PSC-MC had lower denaturation temperatures (32.2 °C and 29.0 °C for ASC-MC and PSC-MC, respectively) compared to mammalian collagen due to their low imino acid content (197.6 and 195.2 residues/1000 residues for ASC-MC and PSC-MC, respectively). ASC-MC and PSC-MC were mainly composed of type I collagen on the literatures and results of amino acid composition, SDS-PAGE pattern, ultraviolet (UV) and Fourier-transform infrared spectroscopy (FTIR) spectra. The maximum solubility of ASC-MC and PSC-MC was appeared at pH 1–3 and a sharp decrease in solubility was observed when the NaCl concentration was above 2%. Zeta potential studies indicated that ASC-MC and PSC-MC exhibited a net zero charge at pH 6.66 and 6.81, respectively. Furthermore, the scavenging capabilities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, superoxide anion radical and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical of ASC-MC and PSC-MC were positively correlated with their tested concentration ranged from 0 to 5 mg/mL and PSC-MC showed significantly higher activity than that of ASC-MC at most tested concentrations (p < 0.05). In addition, the scavenging capability of PSC-MC on hydroxyl radical and superoxide anion radical was higher than those of DPPH radical and ABTS radical, which suggested that ASC-SC and PSC-SC might be served as hydroxyl radical and superoxide anion radical scavenger in cosmeceutical products for protecting skins from photoaging and ultraviolet damage.

scholarly journals Morphology and molecular characterization of newly isolated microalgae strain Chlorella volutis LIPI13-WKT066 from Wakatobi Islands and its potential use

2019 ◽  
Vol 23 (1) ◽  
pp. 13
Author(s):  
Delicia Yunita Rahman ◽  
Swastika Praharyawan ◽  
Sapto Raharjo ◽  
Farizul Fadiyah ◽  
Dwi Susilaningsih
Keyword(s):  
Amino Acid ◽  
Molecular Characterization ◽  
Acid Content ◽  
National Park ◽  
Amino Acid Content ◽  
Morphological Observation ◽  
Future Application ◽  
Health Application ◽  
Potential Use

Morphology and molecular characterization of microalgae isolated from Wakatobi Marine National Park was conducted. An understanding of the characteristics of morphology, molecular, as well as metabolites profile of the microalgae species is potentially useful for its future application. The primary aim of this study was to isolate, identify and characterize the microalgae strain isolated from Wakatobi Marine National Park labeled as LIPI13-WKT066 with the emphasis on the evaluation of amino acid content as a basis for its health application. Morphological observation under the microscope and molecular identification suggested that the microalgae strain of LIPI13-WKT066 belong to the strain under species of Chlorella volutis. Metabolite characterization of the microalgae strain showed that the content of protein (11.9%), lipid (12.4%) and carbohydrate (4.7%) was in the regular range. Further analysis of its amino acid content revealed the potency of the microalgae strain to be used as antihypertensive agent.

scholarly journals Diverse Mechanisms of Antimicrobial Activities of Lactoferrins, Lactoferricins, and Other Lactoferrin-Derived Peptides

2021 ◽  
Vol 22 (20) ◽  
pp. 11264
Author(s):  
Špela Gruden ◽  
Nataša Poklar Ulrih
Keyword(s):  
Antimicrobial Activity ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Molecular Level ◽  
Antioxidant Activities ◽  
Antimicrobial Activities ◽  
Iron Binding ◽  
Primary Focus ◽  
Binding Glycoprotein

Lactoferrins are an iron-binding glycoprotein that have important protective roles in the mammalian body through their numerous functions, which include antimicrobial, antitumor, anti-inflammatory, immunomodulatory, and antioxidant activities. Among these, their antimicrobial activity has been the most studied, although the mechanism behind antimicrobial activities remains to be elucidated. Thirty years ago, the first lactoferrin-derived peptide was isolated and showed higher antimicrobial activity than the native lactoferrin lactoferricin. Since then, numerous studies have investigated the antimicrobial potencies of lactoferrins, lactoferricins, and other lactoferrin-derived peptides to better understand their antimicrobial activities at the molecular level. This review defines the current antibacterial, antiviral, antifungal, and antiparasitic activities of lactoferrins, lactoferricins, and lactoferrin-derived peptides. The primary focus is on their different mechanisms of activity against bacteria, viruses, fungi, and parasites. The role of their structure, amino-acid composition, conformation, charge, hydrophobicity, and other factors that affect their mechanisms of antimicrobial activity are also reviewed.

scholarly journals A novel DNA-binding motif in the nuclear matrix attachment DNA-binding protein SATB1

1994 ◽  
Vol 14 (3) ◽  
pp. 1852-1860
Author(s):  
K Nakagomi ◽  
Y Kohwi ◽  
L A Dickinson ◽  
T Kohwi-Shigematsu
Keyword(s):  
Amino Acid ◽  
Dna Binding ◽  
Direct Contact ◽  
Binding Protein ◽  
Binding Activity ◽  
Binding Domain ◽  
Binding Motif ◽  
Dna Binding Domain ◽  
Sequence Context ◽  
Dna Binding Activity

The nuclear matrix attachment DNA (MAR) binding protein SATB1 is a sequence context-specific binding protein that binds in the minor groove, making virtually no contact with the DNA bases. The SATB1 binding sites consist of a special AT-rich sequence context in which one strand is well-mixed A's, T's, and C's, excluding G's (ATC sequences), which is typically found in clusters within different MARs. To determine the extent of conservation of the SATB1 gene among different species, we cloned a mouse homolog of the human STAB1 cDNA from a cDNA expression library of the mouse thymus, the tissue in which this protein is predominantly expressed. This mouse cDNA encodes a 764-amino-acid protein with a 98% homology in amino acid sequence to the human SATB1 originally cloned from testis. To characterize the DNA binding domain of this novel class of protein, we used the mouse SATB1 cDNA and delineated a 150-amino-acid polypeptide as the binding domain. This region confers full DNA binding activity, recognizes the specific sequence context, and makes direct contact with DNA at the same nucleotides as the whole protein. This DNA binding domain contains a novel DNA binding motif: when no more than 21 amino acids at either the N- or C-terminal end of the binding domain are deleted, the majority of the DNA binding activity is lost. The concomitant presence of both terminal sequences is mandatory for binding. These two terminal regions consist of hydrophilic amino acids and share homologous sequences that are different from those of any known DNA binding motifs. We propose that the DNA binding region of SATB1 extends its two terminal regions toward DNA to make direct contact with DNA.

scholarly journals Six-coordinate oxime-imine cobalt(III) complexes with amino acid co-ligands; synthesis and characterisation

2013 ◽  
Vol 10 (3) ◽  
pp. 792-802
Author(s):  
Baghdad Science Journal
Keyword(s):  
Molecular Structure ◽  
Amino Acid ◽  
Complex Formation ◽  
Octahedral Geometry ◽  
Spectroscopic Methods ◽  
Analysis Program ◽  
Carboxylate Groups ◽  
Physico Chemical ◽  
Butanedione Monoxime ◽  
Coordinate Geometry

In this publication, several six coordinate Co(III)-complexes are reported. The reaction of 2,3-butanedione monoxime with ethylenediamine or o-phenylenediamine in mole ratios of 2:1 gave the tetradentate imine-oxime ligands diaminoethane-N,N`-bis(2-butylidine-3-onedioxime) H2L1 and o-phenylenediamine-N,N`-bis(2-butylidine-3-onedioxime), respectively. The reaction of H2L1 and H2L2 with Co(NO3)2, and the amino acid co-ligands (glycine or serine) resulted in the formation of the required complexes. Upon complex formation, the ligands behave as a neutral tetradantate species, while the amino acid co-ligand acts as a monobasic species. The mode of bonding and overall geometry of the complexes were determined through physico-chemical and spectroscopic methods. These studies revealed octahedral geometry about Co(III) complexes in which the co-ligands bound through the amine and the carboxylate groups. Molecular structure for the complexes have been optimised by CS Chem 3D Ultra Molecular Modelling and Analysis Program and supported six coordinate geometry.

scholarly journals Identification of amino acids essential for DNA binding and dimerization in p67SRF: implications for a novel DNA-binding motif

1993 ◽  
Vol 13 (1) ◽  
pp. 123-132
Author(s):  
A D Sharrocks ◽  
H Gille ◽  
P E Shaw
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Dna Binding ◽  
Transcriptional Activation ◽  
Serum Response Factor ◽  
Alpha Helix ◽  
Site Directed Mutagenesis ◽  
Binding Motif ◽  
Amino Acid Peptide ◽  
Serum Response

The serum response factor (p67SRF) binds to a palindromic sequence in the c-fos serum response element (SRE). A second protein, p62TCF binds in conjunction with p67SRF to form a ternary complex, and it is through this complex that growth factor-induced transcriptional activation of c-fos is thought to take place. A 90-amino-acid peptide, coreSRF, is capable for dimerizing, binding DNA, and recruiting p62TCF. By using extensive site-directed mutagenesis we have investigated the role of individual coreSRF amino acids in DNA binding. Mutant phenotypes were defined by gel retardation and cross-linking analyses. Our results have identified residues essential for either DNA binding or dimerization. Three essential basic amino acids whose conservative mutation severely reduced DNA binding were identified. Evidence which is consistent with these residues being on the face of a DNA binding alpha-helix is presented. A phenylalanine residue and a hexameric hydrophobic box are identified as essential for dimerization. The amino acid phasing is consistent with the dimerization interface being presented as a continuous region on a beta-strand. A putative second alpha-helix acts as a linker between these two regions. This study indicates that p67SRF is a member of a protein family which, in common with many DNA binding proteins, utilize an alpha-helix for DNA binding. However, this alpha-helix is contained within a novel domain structure.

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