title: Partial purification and characterization of thermostable acid phosphatase from thermoacidophilic archaeon Sulfolobus acidocaldarius.
abstract: Thermostable acid phosphatase (APase) from thermoacidophilic archaeon Sulfolobus acidocaldarius was isolated, partially purified, and characterized. The optimum pH and temperature of the enzyme for p-nitrophenylphosphate (pNPP) as a substrate were 5.0 and 70 degrees C, respectively. The apparent K(m) value was 1.9 mM. This APase showed a native molecular mass of 20 kDa on a gel filtration chromatography. Of the APase activity, 60% remained after 60 min of heat treatment at 75 degrees C. To confirm whether the APase is active in the monomeric form, we attempted to elute the enzyme from SDS-polyacrylamide gels with Disk electrophoresis apparatus and renature the enzyme. The APase activity was recovered up to 50% in the 14- to 35-kDa range, and maximum around 25 kDa. These results suggest that this APase is monomeric protein.
authors.affiliation: Department of Bioengineering, Faculty of Engineering, Soka University, 1-236 Tangi-cho, Hachioji, Tokyo 192-8577, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kurosawa
authors.forename: K
authors.initials: K
authors.lastname: Fukuda
authors.forename: Y H
authors.initials: YH
authors.lastname: Itoh
authors.forename: T
authors.initials: T
authors.lastname: Horiuchi
mesh_terms: D000135:Acid Phosphatase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D016944:Sulfolobus / Q000201:enzymology* / Q000254:growth & development; D013696:Temperature
chemical_list: D000135:Acid Phosphatase