How to Label Protease Substrate Products
Things You'll Need
- Target molecule cocktail
- Fluorescent dye labeling kit
- Fluorescence reading instrument
Instructions
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How to Label Protease Substrate Products
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1
Choose your fluorescent dye. Common dyes include rhodamine and fluorescein. These can usually be purchased from manufacturers.
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2
Run the reaction and remove unused fluorophore from target molecules by using size exclusion chromatography (a process that separates molecules based on their size). Dye Removal Columns are also commonly used. These are often advertised with labeling kits.
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3
Detect the molecules. Use a fluorescence reading instrument, such as a fluorescence microscope. Light of a specific wavelength is passed through the molecule (indirectly for some techniques), illuminating the fluorophore.
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4
Take your measurements. Because assays measure either how much substrate was consumed or the amount of product released over a period of time, enzyme amounts can be measured in moles (physical quantity) or in enzyme units (activity).
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