A5081140571- Glycosylation and Glycoproteins Research
- Carbohydrate Chemistry and Synthesis
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Pharmacogenetics and Drug Metabolism
- Lignin and Wood Chemistry
- Amino Acid Enzymes and Metabolism
- Thermochemical Biomass Conversion Processes
- Metabolomics and Mass Spectrometry Studies
- Chemical Synthesis and Analysis
- Inflammatory mediators and NSAID effects
- Digestive system and related health
- Alcohol Consumption and Health Effects
- Enzyme Production and Characterization
- Peptidase Inhibition and Analysis
- HIV/AIDS Research and Interventions
- Chemical Reactions and Mechanisms
- Bacterial Genetics and Biotechnology
- Chemical Reaction Mechanisms
- Research on Leishmaniasis Studies
- Growth Hormone and Insulin-like Growth Factors
- Neuroinflammation and Neurodegeneration Mechanisms
- Advanced Cellulose Research Studies
- HIV/AIDS drug development and treatment
- RNA and protein synthesis mechanisms
Purdue University West Lafayette
2018-2023
Gilead Sciences (United States)
2022
Johns Hopkins Medicine
2020-2022
Johns Hopkins University
2020-2022
Georgia State University
2014-2016
AID Atlanta
2015
Alzheimer's disease (AD) is characterized by accumulation of misfolded proteins. Genetic studies implicate microglia, brain-resident phagocytic immune cells, in AD pathogenesis. As positive effectors, microglia clear toxic proteins, whereas as negative they release proinflammatory mediators. An imbalance these functions contributes to progression. Polymorphisms human CD33, an inhibitory microglial receptor, are linked susceptibility; higher CD33 expression correlates with increased risk....
Novel galacto-<italic>N</italic>-biose derivatives and their sialylated form were efficiently synthesized<italic>via</italic>one-pot two-enzyme systems starting with monosaccharides.
N-glycosylation is one of the most prevalence protein post-translational modifications (PTM) which involved in several biological processes. Alternation associated with cellular malfunction and development disease. Thus, investigation crucial for diagnosis treatment Currently, deglycosylation peptide N-glycosidase F commonly used technique analysis. Additionally, a common error site identification, resulting from chemical deamidation, has largely been ignored. In this study, we developed...
Here we report a facile and efficient method for site-directed glycosylation of peptide/protein. The contains two sequential steps: generation GlcNAc-O-peptide/protein, subsequent ligation eukaryotic N-glycan to the GlcNAc moiety. A pharmaceutical peptide, glucagon-like peptide-1 (GLP-1), model protein, bovine α-Crystallin, were successfully glycosylated using such an approach. It was shown that GLP-1 with O-linked maintained unchanged secondary structure after glycosylation, suggesting...
Glucuronidation, a common phase II biotransformation reaction, is one of the major in vitro and vivo metabolism pathways xenobiotics. In this process, glucuronic acid conjugated to drug or metabolite via carboxylic acid, hydroxy, an amino group form acyl-, O-, and/or N-glucuronide metabolites, respectively. This process traditionally thought be detoxification pathway. However, some acyl-glucuronides react with biomolecules vivo, which may result immune-mediated idiosyncratic toxicity (IDT)....
A biotinylated heparosan hexasaccharide was synthesized by a facile chemoenzymatic approach in one-pot multi-enzyme fashion.
Gas-phase reactivities of the phenylcarbyne anion and its four derivatives were studied using a linear quadrupole ion trap mass spectrometer. The anions calculated to have triplet ground state (singlet-triplet splittings 4-9 kcal mol-1), with exception 4-cyanophenylcarbyne that has singlet splitting -1.9 mol-1). Only react acetone dimethyl disulfide via radical mechanisms. On other hand, only abstracts H2O H2C═C═O from acetic acid electrophilic addition reagents anion. Finally, two...
Isomeric O- and N-glucuronides are common drug metabolites produced in phase II of metabolism. Distinguishing these isomers by using analytical techniques has proven challenging. A tandem mass spectrometric method based on gas-phase ion/molecule reactions deprotonated glucuronide with trichlorosilane (HSiCl3) a linear quadrupole ion trap spectrometer is reported here to readily enable differentiation the N-isomers. The major product observed upon HSiCl3 diagnostic adduct that lost two HCl...
Evaluation of the feasibility various mechanisms possibly involved in cellulose fast pyrolysis is challenging. Therefore, selectively 13C-labeled cellotriose, 18O-labeled cellobiose, and 13C- 18O-doubly-labeled cellobiose were synthesized subjected to an atmospheric pressure chemical ionization source a linear quadrupole ion trap/orbitrap mass spectrometer. The initial products immediately quenched, ionized using ammonium cations, subsequently analyzed loss or retention isotope labels upon...
A commercial fast pyrolysis probe coupled with a high-resolution tandem mass spectrometer was employed to identify the initial reactions and products of xylobiose xylotriose, model compounds xylans. Fragmentation reducing end by loss an ethenediol molecule via ring-opening retro-aldol condensation found be dominant pathway for xylobiose, structure product-β-d-xylopyranosylglyceraldehyde-was identified comparing collision-activated dissociation ionized product authentic compound. This...
An all α-linked<italic>Escherichia coli</italic>R3 outer core pentasaccharide was first synthesized. Its corresponding glycoconjugate can elicit specific anti-pentasaccharide antibodies with<italic>in vitro</italic>bactericidal activity.
Inspired by the electron-activated dissociation technique, most potent tool for glycan characterization, we recently developed free radical reagents structural elucidation. However, underlying mechanisms of radical-induced remain unclear and, therefore, hinder rational optimization and interpretation tandem mass spectra, especially accurate assignment relatively low-abundant but information-rich ions. In this work, selectively incorporate 13C and/or 18O isotopes into cellobiose to study...
The levels of potentially mutagenic impurities (PMIs) in active pharmaceutical ingredients are highly regulated and must be below a critical safety threshold. One class PMIs is primary carbamates, which formed during drug manufacturing formulation. To comply with regulations, it critically important to develop analytical techniques that enable the identification carbamates development process. In this study, tandem mass spectrometry combined gas-phase ion–molecule reactions as well...
Acyl glucuronides (AGs) are common metabolites of carboxylic acid-containing compounds. In some circumstances, AGs suspected to be involved in drug toxicity due formation acyl migration products that bind covalently cellular components. The risk this adverse effect has been found correlated with the chemical stability AG, and assays have described monitor by liquid chromatography coupled mass spectrometry (LC-MS). This analysis can challenging as it requires baseline chromatographic...