Reversible systems based on CO2, amino-acids and organic superbases

RSC Advances ◽  
2015 ◽  
Vol 5 (45) ◽  
pp. 35564-35571 ◽  
Author(s):  
Gonçalo V. S. M. Carrera ◽  
Noémi Jordão ◽  
Miguel M. Santos ◽  
Manuel Nunes da Ponte ◽  
Luís C. Branco
Keyword(s):  
Amino Acids ◽  
Ionic Liquids ◽  
Amino Acid ◽  
Molten Salts ◽  
Reversible Systems ◽  
Chiral Amino Acids

Chiral amino-acids in the presence of an organic superbase in a CO2 atmosphere were used to prepare carbamate-based ionic liquids and molten salts. Variation of the superbase and amino acid R-group gave tuneable CO2 release temperatures from the products.

scholarly journals The Relationship between the Structure and Properties of Amino Acid Ionic Liquids

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3252 ◽  
Author(s):  
Paula Ossowicz ◽  
Joanna Klebeko ◽  
Barbara Roman ◽  
Ewa Janus ◽  
Zbigniew Rozwadowski
Keyword(s):  
Amino Acids ◽  
Ionic Liquids ◽  
Amino Acid ◽  
Surface Activity ◽  
Spectroscopic Properties ◽  
Specific Rotation ◽  
Structure And Properties ◽  
Rotation Surface ◽  
Cation Type ◽  
The Relationship

Ionic liquids based on different l-amino acids (glycine, l-valine, l-leucine, l-isoleucine, l-histidine, l-methionine, l-tyrosine, l-tryptophan, l-arginine, and l-threonine) and different cations (tetrabutylammonium (TBA), tributylmethylammonium (tBMA), didecyldimethylammonium (DDA), (2-hydroxyethyl)trimethylammonium (choline) (Chol), alkyl(C12-C14) dimethylbenzylammonium (benzalkonium) (BA), dodecyltrimethylammonium (DDTMA), hexadecyltrimethylammonium (HDTMA), octadecyltrimethylammonium (ODTMA) and 1-ethyl-3-methylimidazolium (EMIM)) have been synthesized and characterized by NMR and FTIR. Viscosity, specific rotation, surface activity, thermal stability (TG), and phase transformations (DSC) have been determined and compared with available data. Furthermore, benzalkonium, didecyldimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, and octadecyltrimethylammonium amino acid ionic liquids have been shown to exhibit surface activity. The dissolution of cellulose in amino acid ionic liquids (AAILs) composed of various cations was also investigated. Cellulose was only dissolved in EMIM salts of amino acids. In particular, the influence of the cation type on selected physicochemical and spectroscopic properties were discussed. The article is a mini review on amino acid ionic liquids.

scholarly journals Biochemical and structural characterization of a highly active branched-chain amino acid aminotransferase from Pseudomonas sp. for efficient biosynthesis of chiral amino acids

2019 ◽  
Author(s):  
Xinxin Zheng ◽  
Yinglu Cui ◽  
Tao Li ◽  
Ruifeng Li ◽  
Lu Guo ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Amino Acids ◽  
Amino Acid ◽  
Unnatural Amino Acids ◽  
Catalytic Mechanism ◽  
Chiral Amines ◽  
Branched Chain Amino Acid ◽  
Chiral Amino Acids ◽  
Branched Chain ◽  
Substrate Spectrum

AbstractAminotransferases (ATs) are important biocatalysts for the synthesis of chiral amines because of their capability of introducing amino group into ketones or keto acids as well as their high enantioselectivity, high regioselectivity and no requirement of external addition of cofactor. Among all ATs, branched-chain amino acid aminotransferase (BCAT) can reversibly catalyse branched-chain amino acids (BCAAs), including L-valine, L-leucine, and L-isoleucine, with α-ketoglutaric acid to form the corresponding ketonic acids and L-glutamic acid. Alternatively, BCATs have been used for the biosynthesis of unnatural amino acids, such as L-tert-leucine. In the present study, the BCAT from Pseudomonas sp. (PsBCAT) was cloned and expressed in Escherichia coli for biochemical and structural analyses. The optimal reaction temperature and pH of PsBCAT were 40 °C and 8.5, respectively. PsBCAT exhibited a comparatively broader substrate spectrum, and showed remarkably high activity with L-leucine, L-valine, L-isoleucine and L-methionine with activities of 105 U/mg, 127 U/mg, 115 U/mg and 98 U/mg, respectively. Additionally, PsBCAT had activities with aromatic L-amino acids, L-histidine, L-lysine, and L-threonine. To analyse the catalytic mechanism of PsBCAT with the broad substrate spectrum, the crystal structure of PsBCAT was also determined. Finally, conjugated with the ornithine aminotransferase (OrnAT) from Bacillus subtilis, the coupled system was applied to the preparation of L-tert-leucine with 83% conversion, which provided an approximately 2.7-fold higher yield than the single BCAT reaction.IMPORTANCEDespite the enormous potential of BCATs, the vast majority of enzymes still lack suitably broad substrate scope and activity, thus new sources and novel enzymes are currently being investigated. Here, we described a previously uncharacterized PsBCAT, which showed a surprisingly wide substrate range and was more active towards BCAAs. This substrate promiscuity is unique for the BCAT family and could prove useful in industrial applications. Based on the determined crystal structure, we found some differences in the organization of the substrate binding cavity, which may influence the substrate specificity of the enzyme. Moreover, we demonstrated efficient biocatalytic asymmetric synthesis of L-tert-leucine using a coupling system, which can be used to remove the inhibitory by-product, and to shift the reaction equilibrium towards the product formation. In summary, the structural and functional characteristics of PsBCAT were analysed in detail, and this information will play an important role in the synthesis of chiral amino acids and will be conducive to industrial production of enantiopure chiral amines by aminotransferase.

Microwave-assisted one pot-synthesis of amino acid ionic liquids in water: simple catalysts for styrene carbonate synthesis under atmospheric pressure of CO2

2014 ◽  
Vol 4 (4) ◽  
pp. 963-970 ◽  
Author(s):  
Kuruppathparambil Roshith Roshan ◽  
Tharun Jose ◽  
Dongwoo Kim ◽  
Kathalikkattil Amal Cherian ◽  
Dae Won Park
Keyword(s):  
Amino Acids ◽  
Ionic Liquids ◽  
Amino Acid ◽  
Atmospheric Pressure ◽  
Microwave Energy ◽  
One Pot ◽  
Microwave Assisted ◽  
One Pot Synthesis ◽  
Styrene Carbonate

A novel variety of ionic liquids based on amino acids is synthesized in water using microwave energy.

scholarly journals Renewable pyridinium ionic liquids from the continuous hydrothermal decarboxylation of furfural-amino acid derived pyridinium zwitterions

2015 ◽  
Vol 17 (8) ◽  
pp. 4151-4156 ◽  
Author(s):  
Sarah Kirchhecker ◽  
Steffen Tröger-Müller ◽  
Sebastian Bake ◽  
Markus Antonietti ◽  
Andreas Taubert ◽  
...  
Keyword(s):  
Amino Acids ◽  
Ionic Liquids ◽  
Amino Acid

Fully renewable pyridinium ionic liquids were synthesised via the hydrothermal decarboxylation of pyridinium zwitterions derived from furfural and amino acids in flow.

scholarly journals Intrinsic MRI contrast from amino acid-based paramagnetic ionic liquids

2020 ◽  
Vol 1 (6) ◽  
pp. 1980-1987
Author(s):  
Praveen Singh Gehlot ◽  
Hariom Gupta ◽  
Mangal Singh Rathore ◽  
Kusum Khatri ◽  
Arvind Kumar
Keyword(s):  
Magnetic Resonance Imaging ◽  
Amino Acids ◽  
Ionic Liquids ◽  
Amino Acid ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Dual Mode ◽  
Mri Contrast ◽  
Magnetic Resonance Imaging Mri ◽  
Natural Amino Acids

Paramagnetic ionic liquids (PMILs) comprising of natural amino acids and tetrachloroferrate(iii) as constituent ions were prepared that act as highly efficient dual mode (T1 and T2) responsive contrast agents for magnetic resonance imaging (MRI).

scholarly journals Simultaneous Measurement of Amino Acid Enantiomers in Aged Mouse Brain Samples by LC/MS/MS Combined with Derivatization Using Nα-(5-Fluoro-2,4-dinitrophenyl)-l-leucinamide (l-FDLA)

Metabolites ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 57
Author(s):  
Taiji Yamamoto ◽  
Keisuke Yaku ◽  
Takashi Nakagawa
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Biological Samples ◽  
Brain Regions ◽  
Reversed Phase ◽  
Aged Mouse ◽  
Amino Acid Enantiomers ◽  
Advantages And Disadvantages ◽  
Brain Functions ◽  
Chiral Amino Acids

d-amino acids have distinct roles from their l-enantiomer. In particular, some d-amino acids function as agonists or antagonists of neuronal receptors and are involved in higher brain functions. Thus, it is important to precisely measure the levels of these amino acid enantiomers in cells and tissues. Various quantification methods have been developed for measurements of chiral amino acids. However, each method has advantages and disadvantages. Additionally, measuring the amino acid enantiomers in crude biological samples requires a higher selectivity. In this study, we developed a quantification method for amino acid enantiomers using derivatization with Nα-(5-Fluoro-2,4-dinitrophenyl)-l-leucinamide (l-FDLA) followed by liquid chromatography–tandem mass spectrometry (LC/MS/MS) with a conventional reversed-phase column. We simultaneously identified 10 chiral amino acids. Furthermore, we applied this method to investigate murine tissue samples and examined the effect of aging on the amino acid levels in aged brain regions. We found that aging decreased the levels of both d-serine and d-aspartate in the hippocampus. In addition, d-Phenylalanine in the thalamus significantly increased with age. In conclusion, our method is suitable for the quantification of the d-amino acids in crude biological samples and may contribute to elucidating the biological roles of chiral amino acids.

scholarly journals Amino acid-derived bisphenolate palladium complexes as C-C coupling catalysts

2021 ◽  
Author(s):  
Eszter Fazekas ◽  
David T Jenkins ◽  
Andrew A Forbes ◽  
Brendan Gallagher ◽  
Georgina Rosair ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Ester ◽  
Amino Acid Ester ◽  
Palladium Complexes ◽  
Synthetic Method ◽  
Naturally Occurring ◽  
Chiral Amino Acids ◽  
Pendant Arms

A series of amine bisphenol (ABP) pro-ligands featuring amino acid ester pendant arms were prepared. Optimisation of the synthetic method allowed the facile incorporation of naturally occurring, chiral amino acids...

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