Name: Recombinant Human Cystatin B Protein (His Tag)
Brand: Beta LifeScience
SKU: BLPSN-1528
Availability: InStock

Recombinant Human Cystatin B Protein (His Tag)

Catalog No.: BLPSN-1528

Product Overview

Tag	His
Host Species	Human
Accession	P04080
Synonym	CST6, EPM1, EPM1A, PME, STFB, ULD
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).
Description	A DNA sequence encoding the human CSTB (P04080) (Met 2-Phe 98) was expressed, with a His tag at the N-terminus.
Source	E.coli
Predicted N Terminal	Met
AA Sequence	Met 2-Phe 98
Molecular Weight	The recombinant human CSTB consisting of 108 a.a. and has a calculated molecular mass of 12.5 kDa. It migrates as an approximately 15 kDa band in SDS-PAGE under reducing conditions.
Purity	>95% as determined by SDS-PAGE
Endotoxin	Please contact us for more information.
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.
Formulation	Lyophilized from sterile 50mM Tris, 50mM NaCl, pH 8.0.
Stability	The recombinant proteins are stable for up to 1 year from date of receipt at -70°C.
Usage	For Research Use Only
Storage	Store the protein under sterile conditions at -20°C to -80°C. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.