Abstract: The present invention provides an assay for detection of oxidized glutathione (GSSG).

Abstract: The invention provides surfactant compounds of formulas I-IX, which can be used in methods for aiding the solubilization, digestion, preparation, analysis, and/or characterization of biological material, for example, proteins or cell membranes. The compounds can also aid in the recovery of peptides generated during protein digestion, particularly for in-gel digestion protocol. Additionally, the compounds can improve enzymatic protein deglycosylation without interfering with downstream sample preparation steps and mass spectrometric analysis. The compounds can be specifically useful as digestion aids that can be decomposed by an acid, by heat, or a combination thereof. Decomposition of the surfactants allows for facile separation from isolated samples, and/or allows for analysis of the sample without interfering with the sensitivity of various analytical techniques.

Abstract: The present invention provides an assay for detection of oxidized glutathione (GSSG).

Abstract: The invention provides compounds, compositions, methods, substrates, and kits useful for analyzing the metabolic activity in cells, tissue, and animals and for screening test compounds for their effect on cytochrome P450 activity. In particular, a one-step and two-step methods using luminogenic molecules, e.g. luciferins or coelenterazines, that are cytochrome P450 substrates and that are also bioluminescent enzyme, e.g., luciferase, pro-substrates are provided. The present method further provides a method for stabilizing and prolonging the luminescent signal in a luciferase-based assay using luciferase stabilizing agents such as reversible lucifetrase inhibitors.

Abstract: The present invention provides compositions and methods for capture and identification of the cellular targets of a bioactive agent. In particular, provided herein are bioactive agents tethered to capture ligand, cellular targets (optionally tagged with a reporter), capture proteins (optionally present as capture fusions), surfaces (e.g., displaying, capture ligands, capture proteins, or capture fusions), and methods of capturing and identifying the cellular targets of a bioactive agent therewith.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: The invention provides compounds, compositions, methods, substrates, and kits useful for analyzing the metabolic activity in cells, tissue, and animals and for screening test compounds for their effect on cytochrome P450 activity. In particular, a one-step and two-step methods using luminogenic molecules, e.g. luciferins or coelenterazines, that are cytochrome P450 substrates and that are also bioluminescent enzyme, e.g., luciferase, pro-substrates are provided. The present method further provides a method for stabilizing and prolonging the luminescent signal in a luciferase-based assay using luciferase stabilizing agents such as reversible luciferase inhibitors.

Abstract: The present invention provides compositions and methods for capture and identification of the cellular targets of a bioactive agent. In particular, provided herein are bioactive agents tethered to capture ligand, cellular targets (optionally tagged with a reporter), capture proteins (optionally present as capture fusions), surfaces (e.g., displaying, capture ligands, capture proteins, or capture fusions), and methods of capturing and identifying the cellular targets of a bioactive agent therewith.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate. Substrates for hydrolases comprising one or more functional groups are also provided, as well as • methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: A method to detect the presence of amount of at least one molecule in a sample which employs a derivative of luciferin or a derivative of a fluorophore is provided. Compounds and compositions for carrying out the methods of the invention are also provided.

Abstract: The present invention provides compounds and methods for assaying redox state of metabolically active cells and methods for assaying enzyme activity and/or metabolite level by coupling to redox defining co-factor NAD(P)/NAD(P)H measurement.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: The present invention provides compounds useful for detection of hydrogen peroxide and methods of using same.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Abstract: The invention provides compounds, compositions, methods, substrates, and kits useful for analyzing the metabolic activity in cells, tissue, and animals and for screening test compounds for their effect on cytochrome P450 activity. In particular, a one-step and two-step methods using luminogenic molecules, e.g. luciferins or coelenterazines, that are cytochrome P450 substrates and that are also bioluminescent enzyme, e.g., luciferase, pro-substrates are provided. The present method further provides a method for stabilizing and prolonging the luminescent signal in a luciferase-based assay using luciferase stabilizing agents such as reversible luciferase inhibitors.

Abstract: A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.