Kallikrein 11 is expressed in brain, skin, ovary and prostate. Increased levels of Kallikrein 11 have been reported in prostate and ovarian carcinoma. It is a serine protease. Kallikrein 11 (KLK11), also known as hippostasin, trypsin-like serine protease and PRSS20, is a member of human tissue kallikrein family.6 Two alternatively spliced forms exist, resulting in 250 (isoform 1) and 282 (isoform 2) amino acid sequences, respectively.1-4. Isoform 1 consists of a signal peptide (residues 1-18), a short pro peptide (residues 19-21) and the mature chain(residues 22-250). Isoform 2 is identical to isoform 1, except that a 32 amino acid segment is inserted in isoform 2 before residue1 in isoform 1. Isoform 1 is predominantly expressed in brain whereas isoform 2 is preferentially expressed in prostate. KLK11 is a novel marker for ovarian and prostate cancer carcinomas.7-9 rhKLK11, after being activated by thermolysin, is active against a thioester substrate. rhKLK11 corresponds to isoform 1.
Source: Human CD33 Signal Peptide (Met 1-Ala 16) Human Kallikrein 11 (Glu 19-Asn 250) HHHHHHHHHHNC
Recombinant human Kallikrein 11 (rhKLK11, residues 19-250)1-4 in the above construct wasexpressed in a murine myeloma cell line, NS0.
Molecular Mass: The purified, secreted rhKLK11 corresponds to the pro form with an N-terminal sequence of E19TRIIKGFE. By SDS-PAGE under reducing conditions, the apparent molecular mass of the pro form is approximately 40kD.
Purity: ≥95%, as determined by SDS-PAGE and visualized by silver stain.
Endotoxin: ≤ 1EU per 1ug of the protein as determined by the LAL method.
Activity: Measured by its activity to cleave a colormetric peptide substrate D-Val-Leu-Lys-ThioBenzyl ester (VLK-SBzl), in the presence of 5,5’Dithio-bis (2-nitrobenzoic acid) (DTNB), as measured using the wavelength at 405nm and the extinction coefficient of 13,260 M-1cm-1.5
Use: To activate rhKLK11, pre-incubate it at 100ug/ml with thermolysin at 10ug/ml in 50mM Tris,10 mM CaCl2, 0.15M NaCl, pH 7.5 (TCN) for 15 min at 37° C. Add EDTA (10mM finalconcentration) to stop thermolysin activity.
Specific activity: Measured with 100uM substrate and 100ng enzyme in 100ul of 50mM Tris, 1M NaCl, 10mM EDTA, pH 8.5, 0.1mM DTNB at RT, is ≥ 450pmoles/min/ug
Activity can be inhibited by AEBSF, dichloroisocoumarin and aprotinin.
Form: Supplied as a 0.2um filtered solution of 25mM Tris, 10mM CaCl2, 0.15M NaCl, pH 7.5 at the concentration of ~0.7 mg/ml.
Shipping: The protein is shipped with ice packs. Samples are stable for up to twelve months at -70°C. This enzyme can be aliquoted and stored under sterile conditions at -20° C to -70° C in a manual defrost freezer for three months without a significant loss of activity. Avoid repeated freeze-thaw cycles
