Publications by authors named "Jessica A Espino"

Monitoring protein structure before and after environmental alterations (e.g., different cell states) can give insights into the role and function of proteins.

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Monitoring protein structure before and after perturbations can give insights into the role and function of proteins. Fast photochemical oxidation of proteins (FPOP) coupled with mass spectrometry (MS) allows monitoring of structural rearrangements by exposing proteins to OH radicals that oxidize solvent accessible residues, indicating protein regions undergoing movement. Some of the benefits of FPOP include high throughput and lack of scrambling due to label irreversibility.

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Fast Photochemical Oxidation of proteins (FPOP) coupled with mass spectrometry (MS) has become an invaluable tool in structural proteomics to interrogate protein interactions, structure, and protein conformational dynamics as a function of solvent accessibility. In recent years, the scope of FPOP, a hydroxyl radical protein foot printing (HRPF) technique, has been expanded to protein labeling in live cell cultures, providing the means to study protein interactions in the convoluted cellular environment. In-cell protein modifications can provide insight into ligand induced structural changes or conformational changes accompanying protein complex formation, all within the cellular context.

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Fast photochemical oxidation of proteins (FPOP) is a hydroxyl radical protein footprinting method that covalently labels solvent-accessible amino acids by photolysis of hydrogen peroxide. Recently, we expanded the use of FPOP for (IV-FPOP) covalent labeling in . In initial IV-FPOP studies, 545 proteins were oxidatively modified in all body systems within the worm.

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fast photochemical oxidation of proteins (IV-FPOP) is a hydroxyl radical protein footprinting method used to study protein structure and protein-protein interactions. Oxidatively modified proteins by IV-FPOP are analyzed by mass spectrometry (MS), and the extent of oxidation is quantified by label-free MS. Peptide oxidation changes yield useful information about protein structure, due to changes in solvent accessibility.

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Fast oxidation of proteins (FPOP) is a hydroxyl radical protein footprinting (HRPF) method used to study protein structure, protein-ligand interactions, and protein-protein interactions. FPOP utilizes a KrF excimer laser at 248 nm for photolysis of hydrogen peroxide to generate hydroxyl radicals which in turn oxidatively modify solvent-accessible amino acid side chains. Recently, we expanded the use of FPOP of in vivo oxidative labeling in Caenorhabditis elegans (C.

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Fast photochemical oxidation of proteins (FPOP) is a hydroxyl radical protein footprinting method used to characterize protein structure and interactions. FPOP uses a 248 nm excimer laser to photolyze hydrogen peroxide producing hydroxyl radicals. These radicals oxidatively modify solvent exposed side chains of 19 of the 20 amino acids.

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Fast photochemical oxidation of proteins (FPOP) is a protein footprinting technique that is being increasingly used in MS-based proteomics. FPOP is utilized to study protein-protein interactions, protein-ligand interactions, and protein conformational dynamics. This method has recently been extended to protein labeling in live cells (IC-FPOP), allowing the study of protein conformations in the complex cellular environment.

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Protein footprinting coupled with mass spectrometry is being increasingly used for the study of protein interactions and conformations. The hydroxyl radical footprinting method, fast photochemical oxidation of proteins (FPOP), utilizes hydroxyl radicals to oxidatively modify solvent accessible amino acids. Here, we describe the further development of FPOP for protein structural analysis in vivo (IV-FPOP) with Caenorhabditis elegans.

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Fast photochemical oxidation of proteins (FPOP) has become a valuable tool for protein structural characterization. The method has recently been demonstrated to oxidatively modify solvent-accessible sites of proteins inside live cells (IC-FPOP). However, the flow system used for in vitro analysis is not well-suited for IC-FPOP as a number of factors can lead to cell aggregation, causing inconsistent labeling and clogging.

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Hydroxyl radical protein footprinting coupled with mass spectrometry has become an invaluable technique for protein structural characterization. In this method, hydroxyl radicals react with solvent exposed amino acid side chains producing stable, covalently attached labels. Although this technique yields beneficial information, the extensive list of known oxidation products produced make the identification and quantitation process considerably complex.

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Protein footprinting coupled with mass spectrometry has become a widely used tool for the study of protein-protein and protein-ligand interactions and protein conformational change. These methods provide residue-level analysis on protein interaction sites and have been successful in studying proteins in vitro. The extension of these methods for in cell footprinting would open an avenue to study proteins that are not amenable for in vitro studies and would probe proteins in their native environment.

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