Laurent Bernad

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A luminescent method to individually measure the chymotrypsin-like, trypsin-like, or caspase-like activities of the proteasome in cultured cells was developed. Each assay uses a specific luminogenic peptide substrate in a buffer optimized for cell permeabilization, proteasome activity, and luciferase activity. Luminescence is generated in a coupled-enzyme(More)
Novel bioluminogenic substrates were designed for probing monoamine oxidase (MAO) activity based on a simple and effective beta-elimination strategy. By modifying the amino group and the central core of luciferin derivatives, we have developed a series of substrates useful for assays of MAO A or B, or both. One of these substrates, exhibiting low Km values(More)
This article describes a novel two-step homogeneous bioluminescent assay for monoamine oxidase (MAO) that is simple, sensitive, and amenable to high-throughput screening. In the first step, MAO reacts with an aminopropylether analog of methyl ester luciferin. In the second step, a luciferin detection reagent inactivates MAO and converts the product of the(More)
Inflammasomes are protein complexes induced by diverse inflammatory stimuli that activate caspase-1, resulting in the processing and release of cytokines, IL-1β and IL-18, and pyroptosis, an immunogenic form of cell death. To provide a homogeneous method for detecting caspase-1 activity, we developed a bioluminescent, plate-based assay that combines a(More)
Although cytochrome P450 enzymes are responsible for the majority of drug metabolism reactions, the monoamine oxidases (MAOs) are arguably the second-most important phase I biotransformation enzymes. MAOs catalyze the oxidative deamination of a number of biogenic and xenobiotic amines to the corresponding aldehydes with consumption of O2 and production of(More)
A bioluminescent general protease assay was developed using a combination of five luminogenic peptide substrates. The peptide-conjugated luciferin substrates were combined with luciferase to form a homogeneous, coupled-enzyme assay. This single-reagent format minimized backgrounds, gave stable signals, and reached peak sensitivity within 30 min. The(More)
Highly sensitive self-cleavable trimethyl lock quinone-luciferin substrates for diaphorase were designed and synthesized to measure NAD(P)H in biological samples and monitor viable cells via NAD(P)H-dependent cellular oxidoreductase enzymes and their NAD(P)H cofactors.
The aldehyde dehydrogenase (ALDH) family of enzymes is critical for cell survival and adaptation to cellular and environmental stress. These enzymes are of interest as therapeutic targets and as biomarkers of stem cells. This article describes a novel, homogeneous bioluminescence assay to study the activity of the ALDH enzymes. The assay is based on a(More)
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