Synthesis and Characterization of Bis-Triazolyl-Pyridine Derivatives as Noncanonical DNA-Interacting Compounds

Besides the well-known double-helical conformation, DNA is capable of folding into various noncanonical arrangements, such as G-quadruplexes (G4s) and i-motifs (iMs), whose occurrence in gene promoters, replication origins, and telomeres highlights the breadth of biological processes that they might regulate. Particularly, previous studies have reported that G4 and iM structures may play different roles in controlling gene transcription. Anyway, molecular tools able to simultaneously stabilize/destabilize those structures are still needed to shed light on what happens at the biological level. Herein, a multicomponent reaction and a click chemistry functionalization were combined to generate a set of 31 bis-triazolyl-pyridine derivatives which were initially screened by circular dichroism for their ability to interact with different G4 and/or iM DNAs and to affect the thermal stability of these structures. All the compounds were then clustered through multivariate data analysis, based on such capability. The most promising compounds were subjected to a further biophysical and biological characterization, leading to the identification of two molecules simultaneously able to stabilize G4s and destabilize iMs, both in vitro and in living cells.

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Synthesis, Inverse Docking-Assisted Identification and in vitro Biological Characterization of Flavonol-based Analogs of Fisetin as c-Kit, CDK2 and mTOR Inhibitors against Melanoma and Non-melanoma Skin Cancer

Bioorganic Chemistry ◽

10.1016/j.bioorg.2020.104595 ◽

2020 ◽

pp. 104595

Author(s):

Tithi Roy ◽

Samuel T. Boateng ◽

Sergette Banang-Mbeumi ◽

Pankaj K. Singh ◽

Pratik Basnet ◽

...

Keyword(s):

Skin Cancer ◽

Mtor Inhibitors ◽

Biological Characterization ◽

Non Melanoma Skin Cancer ◽

Melanoma Skin

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Physical and Biological Characterization of Ferromagnetic Fiber Networks: Effect of Fibrin Deposition on Short-Term In Vitro Responses of Human Osteoblasts

Tissue Engineering Part A ◽

10.1089/ten.tea.2014.0211 ◽

2015 ◽

Vol 21 (3-4) ◽

pp. 463-474 ◽

Cited By ~ 8

Author(s):

Rose L. Spear ◽

Brajith Srigengan ◽

Suresh Neelakantan ◽

Wolfram Bosbach ◽

Roger A. Brooks ◽

...

Keyword(s):

Biological Characterization ◽

Fibrin Deposition ◽

Short Term ◽

Human Osteoblasts ◽

Fiber Networks

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In Vitro Biological Characterization of DCUN1D5 in DNA Damage Response

Asian Pacific Journal of Cancer Prevention ◽

10.7314/apjcp.2012.13.8.4157 ◽

2012 ◽

Vol 13 (8) ◽

pp. 4157-4162 ◽

Cited By ~ 5

Author(s):

Wei Guo ◽

Guo-Jun Li ◽

Hong-Bo Xu ◽

Jie-Shi Xie ◽

Tai-Ping Shi ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Biological Characterization ◽

Damage Response

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Preparation and Biological Evaluation of Si-Substituted HA Ceramics with Controlled Composition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.1059 ◽

2007 ◽

Vol 361-363 ◽

pp. 1059-1062

Author(s):

Mickael Palard ◽

J. Combes ◽

Eric Champion ◽

Didier Bernache-Assollant

Keyword(s):

Thermal Treatment ◽

Biological Evaluation ◽

Precipitation Process ◽

Biological Characterization ◽

Hydroxyapatite Ceramics

This work aimed at preparing dense and monophasic silicated hydroxyapatite ceramics over the range 0 ≤ x ≤ 1.0 mol of silicon. The synthesis of the powder via an aqueous precipitation process followed by an adapted thermal treatment showed that it was possible to obtain dense single-phased apatite ceramics containing up to 0.6 mol of silicon. The in vitro biological characterization of these materials was performed.

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Biological characterization of charge isomers of human growth hormone

Acta Endocrinologica ◽

10.1530/acta.0.1180014 ◽

1988 ◽

Vol 118 (1) ◽

pp. 14-21 ◽

Cited By ~ 11

Author(s):

A. Skottner ◽

A. Forsman ◽

B. Skoog ◽

J. L. Kostyo ◽

C. M. Cameron ◽

...

Keyword(s):

Biological Activity ◽

Biological Activities ◽

Human Growth ◽

Proteolytic Processing ◽

Biological Characterization ◽

Growth Promoting ◽

Rat Adipose Tissue ◽

Insulin Like Activity

Abstract. Since deamidation of the human GH molecule may alter the manner and extent to which the hormone is cleaved by proteases, and since it has been repeatedly suggested that proteolytic processing is required for the expression of certain of the activities of GH, the present study was conducted to determine whether the biological activity profiles of more acidic forms of human GH are altered. Three charge isomers, GH-b, GH-c and GH-d, representing primarily deamidated forms, were isolated from a native human GH preparation (Crescormon®) in amounts adequate for characterization of their biological activities. All three were essentially equipotent in a radioimmunoassay for human GH. When assessed for growth-promoting activity in the hypophysectomized rat, the isomers were again equipotent with each other and with the GH preparation from which they were derived. The charge isomers also had significant in vitro insulin-like activity on isolated rat adipose tissue and diabetogenic activity in the ob/ob mouse. Thus, the biological activity profiles of these charge isomers of human GH do not differ greatly from one another.

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In vitro biological characterization of macroporous 3D Bonelike® structures prepared through a 3D machining technique

Materials Science and Engineering C ◽

10.1016/j.msec.2008.08.009 ◽

2009 ◽

Vol 29 (3) ◽

pp. 930-935 ◽

Cited By ~ 2

Author(s):

M.S. Laranjeira ◽

A.G. Dias ◽

J.D. Santos ◽

M.H. Fernandes

Keyword(s):

Biological Characterization

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Structural and Functional Characterization of RecG Helicase under Dilute and Molecular Crowding Conditions

Journal of Nucleic Acids ◽

10.1155/2012/392039 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8

Author(s):

Sarika Saxena ◽

Satoru Nagatoishi ◽

Daisuke Miyoshi ◽

Naoki Sugimoto

Keyword(s):

Functional Characterization ◽

Cd Spectroscopy ◽

Helical Conformation ◽

Atp Binding ◽

Molecular Crowding ◽

Active Structure ◽

Dna Junctions ◽

Unique Protein

In an ATP-dependent reaction, theEscherichia coliRecG helicase unwinds DNA junctionsin vitro. We present evidence of a unique protein conformational change in the RecG helicase from anα-helix to aβ-strand upon an ATP binding under dilute conditions using circular dichroism (CD) spectroscopy. In contrast, under molecular crowding conditions, theα-helical conformation was stable even upon an ATP binding. These distinct conformational behaviors were observed to be independent of Na+and Mg2+. Interestingly, CD measurements demonstrated that the spectra of a frayed duplex decreased with increasing of the RecG concentration both under dilute and molecular crowding conditions in the presence of ATP, suggesting that RecG unwound the frayed duplex. Our findings raise the possibility that theα-helix andβ-strand forms of RecG are a preactive and an active structure with the helicase activity, respectively.

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Molecular characterization of human stathmin expressed in Escherichia coli: site-directed mutagenesis of two phosphorylatable serines (Ser-25 and Ser-63)

Biochemical Journal ◽

10.1042/bj3000331 ◽

1994 ◽

Vol 300 (2) ◽

pp. 331-338 ◽

Cited By ~ 31

Author(s):

P A Curmi ◽

A Maucuer ◽

S Asselin ◽

M Lecourtois ◽

A Chaffotte ◽

...

Keyword(s):

Escherichia Coli ◽

Protein Kinase ◽

Glutamic Acid ◽

Protein Characterization ◽

Mitogen Activated Protein Kinase ◽

Helical Conformation ◽

In Vitro Mutagenesis ◽

Native Protein

Stathmin, a probable relay protein possibly integrating multiple intracellular regulatory signals [reviewed in Sobel (1991) Trends Biochem. Sci. 16, 301-305], was expressed in Escherichia coli at levels as high as 20% of total bacterial protein. Characterization of the purified recombinant protein revealed that it had biochemical properties very similar to those of the native protein. It is a good substrate for both cyclic AMP-dependent protein kinase (PKA) and p34cdc2, on the same four sites as the native eukaryotic protein. As shown by m.s., the difference in isoelectric points from the native protein is probably due to the absence of acetylation of the protein produced in bacteria. C.d. studies indicate that stathmin probably contains about 45% of its sequence in an alpha-helical conformation, as also predicted for the sequence between residues 47 and 124 by computer analysis. Replacement of Ser-63 by alanine by in vitro mutagenesis resulted in a ten times less efficient phosphorylation of stathmin by PKA which occurred solely on Ser-16, confirming that Ser-63 is the major target of this kinase. Replacement of Ser-25, the major site phosphorylated by mitogen-activated protein kinase in vitro and in vivo, by the charged amino acid glutamic acid reproduced, in conjunction with the phosphorylation of Ser-16 by PKA, the mobility shift on SDS/polyacrylamide gels induced by the phosphorylation of Ser-25. This result strongly suggests that glutamic acid in position 25 is able to mimic the putative interactions of phosphoserine-25 with phosphoserine-16, as well as the resulting conformational changes that are probably also related to the functional regulation of stathmin.

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Endobrevin, a Novel Synaptobrevin/VAMP-Like Protein Preferentially Associated with the Early Endosome

Molecular Biology of the Cell ◽

10.1091/mbc.9.6.1549 ◽

1998 ◽

Vol 9 (6) ◽

pp. 1549-1563 ◽

Cited By ~ 86

Author(s):

Siew Heng Wong ◽

Tao Zhang ◽

Yue Xu ◽

V. Nathan Subramaniam ◽

Gareth Griffiths ◽

...

Keyword(s):

Synaptic Vesicles ◽

Early Endosome ◽

Biological Characterization ◽

Binding Assays ◽

Indirect Immunofluorescence Microscopy ◽

General Importance ◽

Vitro Binding ◽

Main Components

Synaptobrevins/vesicle-associated membrane proteins (VAMPs) together with syntaxins and a synaptosome-associated protein of 25 kDa (SNAP-25) are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. We report here the molecular, biochemical, and cell biological characterization of a novel member of the synaptobrevin/VAMP family. The amino acid sequence of endobrevin has 32, 33, and 31% identity to those of synaptobrevin/VAMP-1, synaptobrevin/VAMP-2, and cellubrevin, respectively. Membrane fractionation studies demonstrate that endobrevin is enriched in membrane fractions that are also enriched in the asialoglycoprotein receptor. Indirect immunofluorescence microscopy establishes that endobrevin is primarily associated with the perinuclear vesicular structures of the early endocytic compartment. The preferential association of endobrevin with the early endosome was further established by electron microscopy (EM) immunogold labeling. In vitro binding assays show that endobrevin interacts with immobilized recombinant α-SNAP fused to glutathioneS-transferase (GST). Our results highlight the general importance of members of the synaptobrevin/VAMP protein family in membrane traffic and provide new avenues for future functional and mechanistic studies of this protein as well as the endocytotic pathway.

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