Human kallistatin, a new tissue kallikrein-binding protein: purification and characterization.
A new and specific tissue kallikrein-binding protein was identified in mammalian serum and in secreted transformed-cell culture media (Chao et al., Biochem. J. 239: 325-331, 1986). We have designated this kallikrein-binding protein as "kallistatin". Human kallistatin has been purified from serum, using chromatographic steps including DEAE-Sephadex, hydroxylapatite, Cibacron blue-Sepharose, Sephacryl S200, and preparative polyacrylamide gel electrophoresis. The purified kallistatin consists of a single polypeptide chain with an apparent molecular weight of approximately 54 kDa and isoelectric point of approximately 5.0. Kallistatin was eluted as a single peak on reverse-phase HPLC. The purified kallistatin and 125I-labelled human tissue kallikrein form a approximately a 92 kDa SDS- and heat-stable complex. The complex formation is pH dependent and is inhibited by 0.1% (W/V) of deoxycholate or SDS but not by 0.5% (W/V) of Triton X-100, digitonin, Lubrol or CHAPS. A approximately 54 kDa protein was identified in partially purified kallistatin by polyclonal anti-kallistatin antibodies in Western blot analysis and by its binding to 125I-labelled-human tissue kallikrein in ligand blotting. The role of kallistatin in regulating tissue kallikrein activity and metabolism may now be evaluated.
Wang
M Y
MY
Department of Pharmacology, Medical University of South Carolina, Charleston 29425.
Day
J
J
Chao
L
L
Chao
J
J
D015153:Blotting, Western; D002352:Carrier Proteins / Q000097:blood* / Q000302:isolation & purification / Q000378:metabolism; D002845:Chromatography; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D017886:Durapatite; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D006882:Hydroxyapatites; D007610:Kallikreins / Q000378:metabolism* / Q000652:urine; D008970:Molecular Weight
D002352:Carrier Proteins; D006882:Hydroxyapatites; D017886:Durapatite; D007610:Kallikreins