Irvine Chemistry Lab
X-Lyz™ Proteolysis Assay

To Monitor Proteolysis Activity and Determine Degradation Extent

  1. X-Lyz™ Reagent A
  2. X-Lyz™ Reagent B
  3. Norvaline Standard
  4. User Instruction

Please see the MSDS for safely handling.
Contact us for questions, testing services.

  • 15min quick assay
  • Wide linear range
  • Compatible with reducing agents
  • Suitable for microplates and cuvettes
Product Description

Proteolysis is an important process involved in many biological
pathways and proteomics workflows.  It is often necessary to evaluate
the activity of proteases and monitor the progress of proteolytic
reactions. In the case of peptide mapping, tryptic digestion is routinely
carried out before the quantitative analysis by LC-MS/MS.  However, the
validity of the proteomics data thus obtained largely relies on the
assumption that digestion has been fully driven to completion, but not
yet over-hydrolyzed.  Monitoring the proteolytic degradation is critical for
the downstream operation.

The X-Lyz™ Proteolysis Assay Kit is designed to measure the growing
amount of amino groups in peptides/amino acids generated during
the proteolytic reaction.  The water-compatible reagent reacts with the
primary amines to form a sensitive chromophore; its UV absorbance
at 350nm is linearly proportional to amine concentrations over a wide
linear range (25-6000nmol/mL, Figure 1). By simply reading the
changes in absorbance, the assay may be used to monitor the
progress of hydrolysis as the substrate protein is broken down into
smaller pieces. Furthermore the number of cleavages (degradation
extent) may also be quantitatively calculated by dividing the increased
amount of amines over the substrate concentration. The analysis is
easy to operate compared to other methods, such as
trinitrobenzenesulfonic acid (TNBS), known as a dangerous explosive
substance.  The rapid color development of the X-Lyz™ reagent is
complete after 15min incubation. The method is compatible with
commonly used materials in the laboratory, such as reducing agents,
detergents, alcohols, carbohydrates, and inorganic salts. It is suitable
for assays both in microplates and test tube (cuvettes).  More details
may be found in the instruction below.

Figure 1: Standard Curve of Norvaline Concentration vs
Absorbance. The assay was conducted in 96-well plate
WR/Sample 10/1, sample size 25µL.
Catalog #
User Instructions
# of Assays
# of Assays
Test Tube
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