Recombinant Human Cystatin B/CSTB Protein (His Tag)

Specifications

Catalog number

PKSH031609

Size / count

100 µg

Dry ice

No

Hazardous

No

Discontinued

No

Background

Cystatin-B, also known as CPI-B, Liver thiol proteinase inhibitor, Stefin-B, CSTB and CST6, is a cytoplasm and nucleus protein which belongs to thecystatin family. Cystatin-B / CSTB is an intracellular thiol proteinase inhibitor. Tightly binding reversible inhibitor of cathepsins L, H and B. Cystatin-B / CSTB is able to form a dimer stabilized by noncovalent forces, inhibiting papain and cathepsins l, h and b. Cystatin-B / CSTB is also thought to play a role in protecting against the proteases leaking from lysosomes. Defects in Cystatin-B / CSTB are the cause of progressive myoclonic epilepsy type 1 (EPM1) which is an autosomal recessive disorder characterized by severe, stimulus-sensitive myoclonus and tonic-clonic seizures. The cystatins are a family of cysteine protease inhibitors with homology to chicken cystatin. Cystatins are physiological inhibitors of cysteine proteinases which are widely distributed in human tissues and fluids. Cystatins typically comprise about 115 amino acids, are largely acidic, contain four conserved cysteine residues known to form two disulfide bonds. Cystatins may be glycosylated and / or phosphorylated, with similarity to fetuins, kininogens, stefins, histidine-rich glycoproteins and cystatin-related proteins. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired inhibitory activity. Cystatins mainly inhibit peptidases belonging to peptidase families C1 (papain family) and C13 (legumain family) .

Synonyms

CST6; EPM1; EPM1A; PME; STFB; ULD

UniProt

P04080

Accession Number

P04080

Expression System

E.coli

Tag

N-His

Sequence

Met 2-Phe 98

Applications

Enzyme

Field of Research

Cell biology

Endotoxin

Please contact us for more information.

Purity

> 95 % as determined by reducing SDS-PAGE.

Bioactivity

Measured by its ability to inhibit papain cleavage of a fluorogenic peptide substrate Z-FR-AMC (R&D Systems, Catalog # ES009) . The IC50 value is < 15 nM.

Reconstitution

Please refer to the printed manual for detailed information.

Shipping Conditions

This product is provided as lyophilized powder which is shipped with ice packs.

Storage Conditions

Generally, lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.

Calculated Molecular Weight

12.5 kDa

Observed Molecular Weight

15 kDa

Species

Human