title: Detection of protein Z in a renal calculus composed of calcium oxalate monohydrate with the use of liquid chromatography-mass spectrometry/mass spectrometry following two-dimensional polyacrylamide gel electrophoresis separation.
abstract: Protein Z, a vitamin K-dependent plasma protein, has been detected for the first time in a renal calculus along with osteopontin and prothrombin. The renal calculus was obtained from a hyperuricemic patient. Following two-dimensional polyacrylamide gel electrophoresis, the calculus was analyzed with the use of liquid chromatography mass spectrometry (LC-MS). The spectrometer was equipped with a nanoelectrospray interface and an ion trap. Four peptides were determined from a protein in the calculus through LC-MS/MS analysis. Tandem mass spectrum database matching tools were used to identify the protein as protein Z. Authentic protein Z was also analyzed using the same method, and all four peptides determined in the calculus were similarly identified. Whereas protein Z has been reported to be one of the vitamin K-dependent calcium-binding proteins, its role has not been well established. The fact that protein Z exists in a renal calculus composed of calcium oxalate will be beneficial in any future investigations into its role in the body.
authors.affiliation: Central Laboratory of Analytical Biochemistry, Teikyo University, Tokyo 173-8605, Japan. kikaneko@pharm.teikyo-u.ac.jp
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Kaneko
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Yamanobe
authors.forename: Kazuya
authors.initials: K
authors.lastname: Nakagomi
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Mawatari
authors.forename: Maki
authors.initials: M
authors.lastname: Onoda
authors.forename: Shin
authors.initials: S
authors.lastname: Fujimori
mesh_terms: D001798:Blood Proteins / Q000032:analysis / Q000302:isolation & purification*; D002129:Calcium Oxalate; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry*; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D014961:X-Ray Diffraction
chemical_list: D001798:Blood Proteins; C026080:plasma protein Z; D002129:Calcium Oxalate