Chiral recognition and discrimination studies of tyrosine enantiomers on (-)-18-crown-6-tetracarboxylic acid as a chiral selector by nuclear magnetic resonance spectroscopy and docking simulations.

Considering the substantial significance of chiral biomolecules, such as amino acids, in our daily routines, we performed chiral recognition and discrimination of tyrosine (Tyr) enantiomers on (-)-(18-crown-6)-2,3,11,12-tetracarboxylic acid [(-)-18-C-6-TA] as crown-ether type chiral selector (CS) by nuclear magnetic resonance (NMR) spectroscopy and docking simulations. In this study, successful discrimination of the enantiomers of Tyr was achieved, as evidenced by the proton chemical shift differences (ΔΔδ) of Tyr enantiomers observed in the H NMR spectra with (-)-18-C-6-TA CS. We compared the results of these two techniques with the findings obtained from high performance liquid chromatography (HPLC) investigations.

Simultaneous enantioselective separation method for thyroid hormones using liquid chromatography-tandem mass spectrometry and its applications.

An analytical method for the simultaneous determination of chiral thyroxine and the related iodinated chiral compounds using LC-MS/MS is introduced in this study. D-Thyroid hormones (THs), which are not commercially available, were produced through the racemization reaction of the L-THs in acetic acid solution containing salicylaldehyde. The solution containing D- and L-THs after the reaction was used for optimizing the chiral separation.

Elevated aldolase 1A, retrogene 1 expression induces cardiac apoptosis in rat experimental autoimmune myocarditis model.

Acute myocarditis is an unpredictable heart disease that is caused by inflammation-associated cell death. Although viral infection and drug exposure are known to induce acute myocarditis, the molecular basis for its development remains undefined. Using proteomics and molecular analyses in myosin-induced rat experimental autoimmune myocarditis (EAM), we identified that elevated expression of aldolase 1A, retrogene 1 (Aldoart1) is critical to induce mitochondrial dysfunction and acute myocarditis development.

Chiral separation of intact amino acids by capillary electrophoresis-mass spectrometry employing a partial filling technique with a crown ether carboxylic acid.

An enantiomeric separation method for underivatized free amino acids (AAs) using a partial filling technique with CE-MS was developed for the determination of D-AAs in vinegars. A typical chiral separation method was performed with different concentrations of (18-crown-6)-2,3,11,12-tetracarboxylic acid (18C6H4) dissolved in water or formic acid as the background electrolyte. Seventeen AAs, excluding proline and asparagine, were separated, showing chiral resolution values (Rs) ranging from 0.

Metabotyping of rice (Oryza sativa L.) for understanding its intrinsic physiology and potential eating quality.

Rice (Oryza sativa L.), the major staple food in many countries, has genetic diversity adapted to different environmental conditions. However, metabolic traits about diverse rice plants are rarely discovered.

Metabolomics Profiling of the Effects of Taurine Supplementation on Dyslipidemia in a High-Fat-Diet-Induced Rat Model by H NMR Spectroscopy.

Metabolomics, the comprehensive study of metabolites, has merged as a potent tool for analyzing complex phenotypes and identifying biomarkers of specific physiological responses and has the potential to lead to innovative therapeutic and diagnostic schemes for many diseases. In a former report, we showed that taurine supplementation considerably ameliorated dyslipidemia in rats fed a high-caloric diet. In this work, we examined the metabolic changes that occur in rat serum after they were fed a normal diet, a high-fat diet, and a high-fat diet containing 2% taurine (tau) by NMR spectroscopy combined with a multivariate statistical analysis containing PCA, PLS-DA, and OPLS-DA.

Metabolic Profiling of Liver Tissue in Diabetic Mice Treated with Artemisia Capillaris and Alisma Rhizome Using LC-MS and CE-MS.

Artemisia Capillaris (AC) and Alisma Rhizome (AR) are natural products for the treatment of liver disorders in oriental medicine clinics. Here, we report metabolomic changes in the evaluation of the treatment effects of AC and AR on fatty livers in diabetic mice, along with a proposition of the underlying metabolic pathway. Hydrophobic and hydrophilic metabolites extracted from mouse livers were analyzed using HPLC-QTOF and CE-QTOF, respectively, to generate metabolic profiles.

A (1)H HR-MAS NMR-Based Metabolomic Study for Metabolic Characterization of Rice Grain from Various Oryza sativa L. Cultivars.

Rice grain metabolites are important for better understanding of the plant physiology of various rice cultivars and thus for developing rice cultivars aimed at providing diverse processed products. However, the variation of global metabolites in rice grains has rarely been explored. Here, we report the identification of intra- or intercellular metabolites in rice (Oryza sativa L.

Investigation of relative metabolic changes in the organs and plasma of rats exposed to X-ray radiation using HR-MAS (1)H NMR and solution (1)H NMR.

Excess exposure to ionizing radiation generates reactive oxygen species and increases the cellular inflammatory response by modifying various metabolic pathways. However, an investigation of metabolic perturbations and organ-specific responses based on the amount of radiation during the acute phase has not been conducted. In this study, high-resolution magic-angle-spinning (HR-MAS) NMR and solution NMR-based metabolic profiling were used to investigate dose-dependent metabolic changes in multiple organs and tissues--including the jejunum, spleen, liver, and plasma--of rats exposed to X-ray radiation.

Novel Structural Components Contribute to the High Thermal Stability of Acyl Carrier Protein from Enterococcus faecalis.

Enterococcus faecalis is a Gram-positive, commensal bacterium that lives in the gastrointestinal tracts of humans and other mammals. It causes severe infections because of high antibiotic resistance. E.

Metabolite Profiling of Diverse Rice Germplasm and Identification of Conserved Metabolic Markers of Rice Roots in Response to Long-Term Mild Salinity Stress.

The sensitivity of rice to salt stress greatly depends on growth stages, organ types and cultivars. Especially, the roots of young rice seedlings are highly salt-sensitive organs that limit plant growth, even under mild soil salinity conditions. In an attempt to identify metabolic markers of rice roots responding to salt stress, metabolite profiling was performed by ¹H-NMR spectroscopy in 38 rice genotypes that varied in biomass accumulation under long-term mild salinity condition.

Chronic repetitive transcranial magnetic stimulation enhances GABAergic and cholinergic metabolism in chronic unpredictable mild stress rat model: ¹H-NMR spectroscopy study at 11.7T.

Gamma-animobutyric acid (GABA) systems are emerging as targets for development of medications for mood disorders. Deficits in GABA-containing neurons are consistently reported in psychiatric disease, particularly in the prefrontal cortex and hippocampus. Repetitive transcranial magnetic stimulation (rTMS) that use magnetic field to stimulate focal cortical regions with electrical current have a potential therapeutic effects with non-invasive and painless method.

Site-directed modification of the adenylation domain of the fusaricidin nonribosomal peptide synthetase for enhanced production of fusaricidin analogs.

Fusaricidins produced by Paenibacillus polymyxa DBB1709 are lipopeptide antibiotics active against fungi and Gram-positive bacteria. The cyclic hexapeptide structures of fusaricidins are synthesized by fusaricidin synthetase, a non-ribosomal peptide synthetase. The adenylation domain of the third module (FusA-A3) can recruit L: -Tyr, L: -Val, L: -Ile, L: -allo-Ile, or L: -Phe, which diversifies the fusaricidin structures.

In vivo and ex vivo evidence for ketamine-induced hyperglutamatergic activity in the cerebral cortex of the rat: Potential relevance to schizophrenia.

Subanesthetic doses of ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, impair prefrontal cortex (PFC) function in the rat and produce symptoms in humans similar to those observed in patients with schizophrenia. In the present study, in vivo (1) H-MRS and ex vivo (1) H high-resolution magic angle spinning (HR-MAS) spectroscopy was used to examine the brain metabolism of rats treated with subanesthetic doses of ketamine (30 mg/kg) for 6 days. A single voxel localization sequence (PRESS, TR/TE = 4000/20 ms and NEX=512) was used to acquire the spectra in a 30-µl voxel positioned in the cerebral cortex (including mainly PFC) of the rats (ketamine group: n=12; saline group: n=12) anesthetized with isoflurane.

Insights into the low adhesive capacity of human T-cadherin from the NMR structure of Its N-terminal extracellular domain.

T-cadherin is unique among the family of type I cadherins, because it lacks transmembrane and cytosolic domains, and attaches to the membrane via a glycophosphoinositol anchor. The N-terminal cadherin repeat of T-cadherin (Tcad1) is approximately 30% identical to E-, N-, and other classical cadherins. However, it lacks many amino acids crucial for their adhesive function of classical cadherins.

Chiral discrimination studies of (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid by high-performance liquid chromatography and NMR spectroscopy.

Chiral discrimination studies using (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) as a chiral selector were performed by high-performance liquid chromatography (HPLC) and NMR spectroscopy. The enantiomers of alanine (Ala) or alanine methyl ester (Ala-ME) were well separated on the chiral stationary phases (CSPs) derived from (+)-18-C-6-TA by HPLC. The chiral selector, (+)-18-C-6-TA, used in the CSP was also applied for the chiral discrimination of the Ala and Ala-ME enantiomers, and it discriminated these enantiomers successfully by NMR spectroscopy.