Expression and enzymatic characterization of recombinant human kallikrein 14.
Human kallikrein 14 (KLK14) is a member of the human kallikrein gene family of serine proteases, and its protein, hK14, has recently been suggested to serve as a new ovarian and breast cancer marker. To gain insights into hK14's physiological functions, the active recombinant enzyme was obtained in an enzymatically pure state for biochemical and enzymatic characterizations. We studied its substrate specificity and behavior to various protease inhibitors, and identified candidate physiological substrates. hK14 had trypsin-like activity with a strong preference for Arg over Lys in the P1 position, and its activity was inhibited by typical serine protease inhibitors. The protease degraded casein, fibronectin, gelatin, collagen type I, collagen type IV, fibrinogen, and high-molecular-weight kininogen. Furthermore, it rapidly hydrolyzed insulin-like growth factor binding protein-3 (IGFBP-3). These findings suggest that hK14 may be implicated in tumor progression in ovarian carcinoma.
Rajapakse
Sanath
S
Laboratory of Molecular and Cellular Interactions, Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan.
Takahashi
Takayuki
T
D014408:Biomarkers, Tumor; D002364:Caseins / Q000378:metabolism; D024042:Collagen Type I / Q000378:metabolism; D024141:Collagen Type IV / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism; D005780:Gelatin / Q000378:metabolism; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism*; D007610:Kallikreins / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000378:metabolism*; D011994:Recombinant Proteins; D012697:Serine Endopeptidases / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors; D013379:Substrate Specificity
D014408:Biomarkers, Tumor; D002364:Caseins; D024042:Collagen Type I; D024141:Collagen Type IV; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D018972:Insulin-Like Growth Factor Binding Protein 3; D011994:Recombinant Proteins; D015842:Serine Proteinase Inhibitors; D005780:Gelatin; D005340:Fibrinogen; C425336:KLK14 protein, human; D007610:Kallikreins; D012697:Serine Endopeptidases