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C6854

Sigma-Aldrich

Cathepsin L from human liver

≥0.5 units/mg protein, solution

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About This Item

CAS Number:
Enzyme Commission number:
MDL number:
UNSPSC Code:
12352200
NACRES:
NA.32

biological source

human liver

Quality Level

form

solution

specific activity

≥0.5 units/mg protein

technique(s)

activity assay: suitable

pH range

4.5—5.5

UniProt accession no.

application(s)

pharmaceutical

shipped in

dry ice

storage temp.

−20°C

Gene Information

human ... CTSL1(1514)

General description

The cathepsin L (CTSL) gene is mapped to human chromosome 9q21.33. It encodes a lysosomal cysteine proteinase that belongs to the peptidase C1 family. The enzyme is a dimer of a heavy (175 amino acids) and a light chain (42 amino acids) linked by disulfide bonds.

Application

Cathepsin L (CTSL) from human liver has been used:
  • to digest mutant transforming growth factor β-induced (TGFBIp) and LC3 (autophagosomes marker) proteins in vitro
  • to digest the pH-dependent fibril of a pre-melanosomal protein (Pmel17) repeat domain (RPT) isoform and study the effect of pH on sRPT aggregation kinetics by tryptophan fluorescence
  • to analyze the inhibition of CTSL by small molecules or drugs in a cell-free system

Biochem/physiol Actions

Cathepsin L (CTSL) exhibits endopeptidase activity and breaks peptide bonds with aromatic residues. This enzyme is functional at pH 3.0–6.5 with thiol compounds. Elastin, collagen, and α-1 protease inhibitors act as substrates for cathepsin L (CTSL). CTSL cleaves several proteins including enzymes, receptors, and transcription factors. It is involved in antigenic peptide production and controls B-cells homeostasis. It is associated with myofibril necrosis and tumor progression. Increased expression of CTSL promotes metastasis and relates to poor prognosis in cancer patients. Increased expression of CTSL is observed in breast cancer. CTSL is implicated in glioblastoma multiforme (GBM), middle east respiratory syndrome (MERS), gingival overgrowth, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has a higher specific activity than cathepsin B and H in the degradation of a variety of physiological protein substrates.

Unit Definition

One unit will hydrolyze 1.0 μmole of Z-Phe-Arg-AFC per minute at pH 5.5 at 25 °C.

Physical form

Solution in in 20 mM malonate, pH 5.5, 1 mM EDTA, and 400 mM NaCl.

Storage Class Code

10 - Combustible liquids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable


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Stefan Tholen et al.
Cellular and molecular life sciences : CMLS, 71(5), 899-916 (2013-07-03)
Endolysosomal cysteine cathepsins functionally cooperate. Cathepsin B (Ctsb) and L (Ctsl) double-knockout mice die 4 weeks after birth accompanied by (autophago-) lysosomal accumulations within neurons. Such accumulations are also observed in mouse embryonic fibroblasts (MEFs) deficient for Ctsb and Ctsl.
Dexter N Dean et al.
Biochimica et biophysica acta. Proteins and proteomics, 1867(10), 961-969 (2019-02-05)
The pre-melanosomal protein (Pmel17) aggregates within melanosomes to form functional amyloid fibrils that facilitate melanin polymerization. The repeat domain (RPT) of Pmel17 fibrillates under strict acidic melanosomal pH. Alternative splicing results in a shortened repeat domain (sRPT), which also forms
M Kathryn Liszewski et al.
Immunity, 39(6), 1143-1157 (2013-12-10)
Complement is viewed as a critical serum-operative component of innate immunity, with processing of its key component, C3, into activation fragments C3a and C3b confined to the extracellular space. We report here that C3 activation also occurred intracellularly. We found
Bailey Miller et al.
Journal of natural products, 77(1), 92-99 (2013-12-25)
A number of marine natural products are potent inhibitors of proteases, an important drug target class in human diseases. Hence, marine cyanobacterial extracts were assessed for inhibitory activity to human cathepsin L. Herein, we have shown that gallinamide A potently
Violeta Morin et al.
PloS one, 7(11), e46850-e46850 (2012-11-13)
Proteolysis of sperm histones in the sea urchin male pronucleus is the consequence of the activation at fertilization of a maternal cysteine protease. We previously showed that this protein is required for male chromatin remodelling and for cell-cycle progression in

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