title: Enzymatic profiling of human kallikrein 14 using phage-display substrate technology.
abstract: The human KLK14 gene is one of the newly identified serine protease genes belonging to the human kallikrein family, which contains 15 members. KLK14 , like all other members of the human kallikrein family, is predicted to encode for a secreted serine protease already found in various biological fluids. This new kallikrein is mainly expressed in prostate and endocrine tissues, but its function is still unknown. Recent studies have demonstrated that KLK14 gene expression is up-regulated in prostate and breast cancer tissues, and that higher expression levels correlate with more aggressive tumors. In this work, we used phage-display substrate technology to study the substrate specificity of hK14. A phage-displayed random pentapeptide library with exhaustive diversity was screened with purified recombinant hK14. Highly specific and sensitive substrates were selected from the library. We show that hK14 has dual activity, trypsin- and chymotrypsin-like, with a preference for cleavage after arginine residues. A SwissProt database search with selected sequences identified six potential human protein substrates for hK14. Two of them, laminin alpha-5 and collagen IV, which are major components of the extracellular matrix, have been demonstrated to be hydrolyzed efficiently by hK14.
authors.affiliation: Urology Research Unit, Department of Urology, CHUV, CH-1066 Epalinges, Switzerland.
authors.forename: Loyse M
authors.initials: LM
authors.lastname: Felber
authors.forename: Carla A
authors.initials: CA
authors.lastname: Borgoño
authors.forename: Sylvain M
authors.initials: SM
authors.lastname: Cloutier
authors.forename: Christoph
authors.initials: C
authors.lastname: Kündig
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Kishi
authors.forename: Jair
authors.initials: J
authors.lastname: Ribeiro Chagas
authors.forename: Patrice
authors.initials: P
authors.lastname: Jichlinski
authors.forename: Christian M
authors.initials: CM
authors.lastname: Gygi
authors.forename: Hans-Jürg
authors.initials: HJ
authors.lastname: Leisinger
authors.forename: Eleftherios P
authors.initials: EP
authors.lastname: Diamandis
authors.forename: David
authors.initials: D
authors.lastname: Deperthes
mesh_terms: D001435:Bacteriophages / Q000235:genetics; D003001:Cloning, Molecular; D024141:Collagen Type IV / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007610:Kallikreins / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D007797:Laminin / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D024141:Collagen Type IV; D016326:Extracellular Matrix Proteins; D007797:Laminin; C425336:KLK14 protein, human; D007610:Kallikreins