UCH-L1 (human), (recombinant) (His-tag)



BML-UW9740-0050	50 µg	336.00 USD
Do you need bulk/larger quantities?

Product Details

Alternative Name:	Ubiquitin C-terminal hydrolase L1, PGP9.5

MW:	24.8 kDa

Source:	Produced in E. coli.

UniProt ID:	P09936

Formulation:	Liquid. In 50 mM TRIS, pH 7.6, containing 1 mM dithiothreitol (DTT).

Specific Activity:	>100 pmol/min/µg. Determined at 25°C with 1 μM ubiquitin-AMC (BML-SE211) as substrate and UCH-L1 (see protocol).

Shipping:	Dry Ice

Long Term Storage:	-80°C

Scientific Background:	Ubiquitin C-terminal hydrolases (UCHs) are a family of cysteine hydrolases that catalyze the hydrolysis of amides, esters and thioesters of the C-terminus of ubiquitin. Mammalian neuronal cells abundantly express a deubiquitylating enzyme, ubiquitin carboxy-terminal hydrolase 1 (UCH-L1). Mutations in UCH-L1 are linked to Parkinson's disease as well as gracile axonal dystrophy (gad) in mice. In contrast to the universally expressed UCH-L3 isozyme, UCH-L1 is expressed exclusively in neurons and testis/ovary. It has been shown that UCH-L1 associates and co-localizes with monoubiquitin and elongates ubiquitin half-life and the suggestion is made that UCH-L1, with avidity and affinity for ubiquitin, ensures ubiquitin stability within neurons.

Protocol:	Components of Assay: Assay Buffer: 50 mM HEPES/NaOH, pH 7.8, 0.5 mM EDTA, 1 mM DTT, 0.1 mg/ml ovalbumin UCH-L1 (BML-UW9740): Dilute to 20-fold the desired final concentration in cold Assay Buffer (e.g. 400 pM/10.8 ng/ml), and keep on ice until use. Ubiquitin-AMC (BML-SE211): 0.542 mg/ml (62 µM) solution in 50 mM sodium acetate, pH 7.0. Prepare a dilution in Assay Buffer which is 20-fold the desired assay concentration. AMC Standard (BML-KI107): 30 µM solution in 50 mM HEPES/NaOH, pH 7.4, 100 mM NaCl, 0.1% CHAPS, 10 mM DTT, 1 mM EDTA, 10% glycerol. Prepare a series of dilutions in Assay Buffer (0-1.0 µM) for use in preparation of a standard curve. ½ Volume 96-well white micro-plate (BML-KI110) Microplate-reading Fluorimeter: Reader should be capable of excitation at a wavelength in the range of 350-380 and detection of emitted light in the range of 440-460 nm. Assay Procedure: Add 90 µl of Assay Buffer to the desired number of microplate wells and warm to assay temperature (e.g. 25°C). Add 5 µl of diluted UCH-L1 and incubate for 30 min. to allow time for DTT-mediated activation of the enzyme. Start the reaction by adding 5 µl of the 20x ubiquitin-AMC and mixing well. The Km of this preparation of UCH-L1 for ubiquitin-AMC was determined to be 57 nM and assays are typically performed at final concentrations in the range of 0-1 µM. Monitor the progress of the reaction by measuring the fluorescence of the AMC cleaved from the ubiquitin-AMC. For example, read fluorescence (Ex. 350-380 nm; Em. 440-460) at 1 min. intervals for 10 min. Determine the fluorescence in wells filled with 100 µl of a series of dilutions of AMC in Assay Buffer (0-1 µM). Plot AMC concentration (µM, y-axis) as a function of fluorescence (arbitrary fluorescence units, AFU, x-axis). Data analysis: A conversion factor relating fluorescence to AMC concentration may be determined from the slope of the line (µM/AFU) obtained in step 5). Initial rates of ubiquitin-AMC cleavage by UCH-L1 may be determined from the slope (AFU/min) of the early, linear part of the reaction progress curve. A rate in, for example, pmol/min, can then be calculated by multiplying the initial slope of the progress curve by the slope of the calibration curve and the reaction volume (100 µl): Rate (pmol/min) = (AFU/min) x (µM/AFU) x (100 µl)

Regulatory Status:	RUO - Research Use Only