What Is L-Aspartic Acid β-(7-Amido-4-Methylcoumarin)?

L-Aspartic acid β-(7-amido-4-methylcoumarin) is a synthetic fluorogenic substrate designed for the detection and quantification of protease and amidase activity. The compound consists of L-aspartic acid linked at its β-carboxyl position to 7-amino-4-methylcoumarin (AMC), a well-established fluorescent reporter molecule.

In its intact form the substrate exhibits minimal fluorescence. Upon enzymatic hydrolysis of the amide bond, free AMC is liberated. AMC fluoresces intensely with an excitation maximum near 380 nm and an emission maximum near 460 nm, providing a sensitive and continuous readout of enzyme activity. This Aladdin product (SKU: L431921) corresponds to the widely referenced Sigma-Aldrich catalog number A1057, facilitating straightforward cross-referencing in published protocols.

How Should This Substrate Be Stored and Handled?

Proper storage and handling are essential to maintain substrate integrity and assay reproducibility. The following general guidelines apply to AMC-conjugated fluorogenic substrates of this class:

• Temperature: Store at −20 °C in a tightly sealed container, protected from light and moisture. Avoid repeated freeze-thaw cycles by preparing single-use aliquots.
• Light sensitivity: AMC-containing compounds are photosensitive. Work under subdued lighting and protect solutions from prolonged exposure to ambient light.
• Solubility: The compound is typically dissolved in dimethyl sulfoxide (DMSO) to prepare concentrated stock solutions (e.g., 10–50 mM). Dilute into aqueous assay buffer immediately before use to minimise hydrolysis and precipitation.
• Stability: Stock solutions in DMSO are generally stable for several months when stored correctly at −20 °C. Aqueous working solutions should be used promptly.

Note: Specific solubility data and confirmed storage conditions for L431921 should be verified against the Certificate of Analysis supplied with the lot.

What Are the Primary Research Applications?

L-Aspartic acid β-(7-amido-4-methylcoumarin) serves as a tool substrate in multiple biochemical and cell-biology workflows:

• Protease activity assays: The substrate is used to measure the hydrolytic activity of aspartyl proteases and other enzymes capable of cleaving β-aspartyl amide bonds, enabling kinetic characterisation (K_m, V_max, k_cat) and inhibitor screening.
• Enzyme inhibitor profiling: Competitive or fluorometric inhibition assays can be performed in microplate format, supporting high-throughput screening of candidate inhibitors.
• Quality control of enzyme preparations: The substrate provides a rapid, sensitive check of enzyme batch activity before use in downstream experiments.
• Mechanistic studies: Researchers use AMC-conjugated substrates to probe specificity determinants of proteases by comparing cleavage rates across structurally related substrates.

The fluorometric format is compatible with standard microplate readers equipped with a violet/UV light source and a 460 nm emission filter, making this substrate accessible to most biochemistry laboratories.

How Do I Order and Cross-Reference This Product?

L-Aspartic acid β-(7-amido-4-methylcoumarin) is available from Aladdin Scientific under SKU L431921. This product corresponds to Sigma-Aldrich catalog number A1057, enabling researchers to cross-reference existing literature protocols that cite the Sigma source without reformulation.

To place an order:

1. Search for SKU L431921 on the Aladdin Scientific website or contact your local Aladdin sales representative.
2. Confirm the required pack size and purity grade with your sales contact or the product page Certificate of Analysis.
3. For institutional or bulk purchasing enquiries, reach out to Aladdin's procurement team for volume pricing and lead-time information.

For technical questions regarding assay setup, compatibility, or specification details, contact Aladdin Scientific technical support, referencing SKU L431921 and lot number for fastest resolution.