Cystatin S / CST4 Recombinant Protein | CST4 recombinant protein

Recombinant Human Cystatin S / CST4 Protein (His tag)

Cat. Num. AAA2545756

• Purity: > 98 % as determined by SDS-PAGE
• Synonyms: Cystatin S / CST4; Recombinant Human Cystatin S / CST4 Protein (His tag); CST4; MGC71923; CST4 recombinant protein

• Host: Human Cells
• Purity/Purification: > 98 % as determined by SDS-PAGE
• Form/Format: Lyophilized from sterile PBS, pH 7.4
• Sequence Length: 141

• Application Notes: The secreted recombinant human CST4 consists of 132 amino acids and migrates as an approximately 16 kDa band in SDS-PAGE under reducing conditions as predicted.
• Predicted N Terminal: Ser 21
• Endotoxin: < 1.0 EU per mug of the protein as determined by the LAL method
• Preparation and Storage: Samples are stable for up to twelve months from date of receipt at -70 degree C

SDS-PAGE

Related Product Information for CST4 recombinant protein

Background: Cystatin-S, also known as Cystatin-4, Salivary acidic protein 1, Cystatin-SA-III and CST4, is a secreted protein which belongs to the cystatin family. Cystatin-4 / CST4 is expressed in submandibular and sublingual saliva but not in parotid saliva (at protein level). It is also expressed in saliva, tears, urine and seminal fluid. The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions. Cystatin-4 / CST4 strongly inhibits papain and ficin, partially inhibits stem bromelain and bovine cathepsin C, but does not inhibit porcine cathepsin B or clostripain. Papain is inhibited non-competitively. Cystatin-4 / CST4 is an S-type cystatin, based on its high level of expression in saliva, tears and seminal plasma. The specific role in these fluids is unclear but antibacterial and antiviral activity is present, consistent with a protective function.

Description: A DNA sequence encoding the human CST4 (NP_001890.1) (Met 1-Ala 141) was fused with a polyhistidine tag at the C-terminus.

NCBI and Uniprot Product Information

• NCBI GI #: 4503109
• NCBI GeneID: 1472
• NCBI Accession #: NP_001890.1
• NCBI GenBank Nucleotide #: NM_001899.2
• UniProt Accession #: P01036; Q9UBI5; Q9UCS9
• Molecular Weight: 16,214 Da
• NCBI Official Full Name: cystatin-S
• NCBI Official Synonym Full Names: cystatin S
• NCBI Official Symbol: CST4
• NCBI Protein Information: cystatin-S
• UniProt Protein Name: Cystatin-S
• Protein Family: Cystatin
• UniProt Gene Name: CST4

NCBI Description

The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions. The cystatin locus on chromosome 20 contains the majority of the type 2 cystatin genes and pseudogenes. This gene is located in the cystatin locus and encodes a type 2 salivary cysteine peptidase inhibitor. The protein is an S-type cystatin, based on its high level of expression in saliva, tears and seminal plasma. The specific role in these fluids is unclear but antibacterial and antiviral activity is present, consistent with a protective function. [provided by RefSeq, Jul 2008]

Uniprot Description

CST4: This protein strongly inhibits papain and ficin, partially inhibits stem bromelain and bovine cathepsin C, but does not inhibit porcine cathepsin B or clostripain. Papain is inhibited non-competitively. Belongs to the cystatin family.

Protein type: Inhibitor; Secreted; Secreted, signal peptide

Chromosomal Location of Human Ortholog: 20p11.21

Cellular Component: extracellular space

Molecular Function: cysteine protease inhibitor activity; protease binding

Biological Process: detection of chemical stimulus involved in sensory perception of bitter taste; negative regulation of proteolysis; retinal homeostasis