Inclusion of naturally occurring amino acids in water soluble calix[4]arenes: a microcalorimetric and1H NMR investigation supported by molecular modeling

2006 ◽  
Vol 4 (2) ◽  
pp. 243-249 ◽  
Author(s):  
Giuseppe Arena ◽  
Alessandro Casnati ◽  
Annalinda Contino ◽  
Antonio Magrì ◽  
Francesco Sansone ◽  
...  
The Analyst ◽  
2015 ◽  
Vol 140 (21) ◽  
pp. 7391-7398 ◽  
Author(s):  
Sivaiah Areti ◽  
Rohit Teotia ◽  
Chebrolu Pulla Rao

A water soluble and biocompatible glucopyranosyl conjugate (L) has been synthesized, characterized and shown to be selective to Cys among the naturally occurring amino acids. TheLshows green fluorescence upon reaction with –SH containing molecules present in biological cells and hence provides cell imaging.


2007 ◽  
Vol 204 (2) ◽  
pp. 393-403 ◽  
Author(s):  
Erica Andersen-Nissen ◽  
Kelly D. Smith ◽  
Richard Bonneau ◽  
Roland K. Strong ◽  
Alan Aderem

The molecular basis for Toll-like receptor (TLR) recognition of microbial ligands is unknown. We demonstrate that mouse and human TLR5 discriminate between different flagellins, and we use this difference to map the flagellin recognition site on TLR5 to 228 amino acids of the extracellular domain. Through molecular modeling of the TLR5 ectodomain, we identify two conserved surface-exposed regions. Mutagenesis studies demonstrate that naturally occurring amino acid variation in TLR5 residue 268 is responsible for human and mouse discrimination between flagellin molecules. Mutations within one conserved surface identify residues D295 and D367 as important for flagellin recognition. These studies localize flagellin recognition to a conserved surface on the modeled TLR5 structure, providing detailed analysis of the interaction of a TLR with its ligand. These findings suggest that ligand binding at the β sheets results in TLR activation and provide a new framework for understanding TLR–agonist interactions.


1988 ◽  
Vol 153 (4) ◽  
pp. 199-200 ◽  
Author(s):  
E. Mikros ◽  
A. Gaudemer ◽  
R. Pasternack

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ramona Wördemann ◽  
Lars Wiefel ◽  
Volker F. Wendisch ◽  
Alexander Steinbüchel

AbstractCyanophycin (multi-l-arginyl-poly-l-aspartic acid; also known as cyanophycin grana peptide [CGP]) is a biopolymer that could be used in various fields, for example, as a potential precursor for the synthesis of polyaspartic acid or for the production of CGP-derived dipeptides. To extend the applications of this polymer, it is therefore of interest to synthesize CGP with different compositions. A recent re-evaluation of the CGP synthesis in C. glutamicum has shown that C. glutamicum is a potentially interesting microorganism for CGP synthesis with a high content of alternative amino acids. This study shows that the amount of alternative amino acids can be increased by using mutants of C. glutamicum with altered amino acid biosynthesis. With the DM1729 mutant, the lysine content in the polymer could be increased up to 33.5 mol%. Furthermore, an ornithine content of up to 12.6 mol% was achieved with ORN2(Pgdh4). How much water-soluble or insoluble CGP is synthesized is strongly related to the used cyanophycin synthetase. CphADh synthesizes soluble CGP exclusively. However, soluble CGP could also be isolated from cells expressing CphA6308Δ1 or CphA6308Δ1_C595S in addition to insoluble CGP in all examined strains. The point mutation in CphA6308Δ1_C595S partially resulted in a higher lysine content. In addition, the CGP content could be increased to 36% of the cell dry weight under optimizing growth conditions in C. glutamicum ATCC13032. All known alternative major amino acids for CGP synthesis (lysine, ornithine, citrulline, and glutamic acid) could be incorporated into CGP in C. glutamicum.


2021 ◽  
Author(s):  
Lamiaa Reda Ahmed ◽  
Ahmed F. M. EL-Mahdy ◽  
Cheng-Tang Pan ◽  
Shiao-Wei Kuo

In this paper, we describe the construction of a new fluorescent hydroxyl- and hydrazone-based covalent organic framework (TFPB-DHTH COF) through the one-pot polycondensation of 1,3,5-tris(4-formylphenyl)benzene (TFPB) and 2,5-dihydroxyterephthalohydrazide (DHTH) under...


2021 ◽  
Vol 26 (3) ◽  
pp. 501-501
Author(s):  
Jun-Ho Kim ◽  
Nam-Hong Kim ◽  
Eun-Ji Kim ◽  
Ji Ho Kim ◽  
Min-Young Lee ◽  
...  

2000 ◽  
Vol 167 (2) ◽  
pp. 247-252 ◽  
Author(s):  
H Wang ◽  
H Wolosker ◽  
J Pevsner ◽  
SH Snyder ◽  
DJ Selkoe

Little evidence is available for the physiological function of D-amino acids in species other than bacteria. Here we demonstrate that naturally occurring freed -aspartate (D-Asp) is present in all magnocellular neurons of rat hypothalamus. The levels of this naturally occurring D-amino acid were elevated during lactation and returned to normal thereafter in the magnocellular neurosecretory system, which produces oxytocin, a hormone responsible for milk ejection during lactation. Intraperitoneal injections of D-Asp reproducibly increased oxytocin gene expression and decreased the concentration of circulating oxytocin in vivo. Similar changes were observed in the vasopressin system. These results provide evidence for the role(s) of naturally occurring free D-Asp in mammalian physiology. The findings argue against the conventional concept that only L-stereoisomers of amino acids are functional in higher species.


ACS Omega ◽  
2021 ◽  
Author(s):  
Deep S. Bhattacharya ◽  
Aishwarya Bapat ◽  
Denis Svechkarev ◽  
Aaron M. Mohs

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1099
Author(s):  
Virginia Aiassa ◽  
Claudia Garnero ◽  
Marcela R. Longhi ◽  
Ariana Zoppi

Cyclodextrins (CDs) are naturally available water-soluble cyclic oligosaccharides widely used as carriers in the pharmaceutical industry for their ability to modulate several properties of drugs through the formation of drug–CD complexes. The addition of an auxiliary substance when forming multicomponent complexes is an adequate strategy to enhance complexation efficiency and to facilitate the therapeutic applicability of different drugs. This review discusses multicomponent complexation using amino acids; organic acids and bases; and water-soluble polymers as auxiliary excipients. Special attention is given to improved properties by including information on the solubility, dissolution, permeation, stability and bioavailability of several relevant drugs. In addition, the use of multicomponent CD complexes to enhance therapeutic drug effects is summarized.


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