title: Stabilization of alkaline phosphatase with Au@Ag2O nanoparticles.
abstract: Here, we report that a conductive Au@Ag(2)O nanoparticle structure significantly enhances the stability of alkaline phosphatase (AlkP) in the presence of the inhibitors urea and l-phenylalanine (Phe). The enzyme/nanoparticle construct is prepared by associating the enzyme with citrate-capped Au particles, and then adding Ag(+). UV-vis and XPS spectroscopy and transmission electron microscopy confirm the core@shell structure. AlkP activity was quantified in the presence and absence of the two inhibitors using a time-resolved colorimetric assay. The results indicate that 21% of the initial active AlkP is incorporated into the nanoparticle structure. More importantly, however, the Au@Ag(2)O core@shell host reduces the inhibitory effect of urea and Phe by factors ranging from 3 to 12, depending on the inhibitor and its concentration, compared to the wild-type enzyme.
authors.affiliation: Department of Chemistry and Biochemistry, Texas Materials Institute, and Center for Nano- and Molecular Science and Technology, The University of Texas at Austin, 1 University Station, A5300, Austin, Texas 78712-0165, USA.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Zaccheo
authors.forename: Richard M
authors.initials: RM
authors.lastname: Crooks
mesh_terms: D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D006046:Gold / Q000737:chemistry* / Q000494:pharmacology*; D053758:Nanoparticles; D010087:Oxides / Q000737:chemistry* / Q000494:pharmacology*; D010649:Phenylalanine / Q000494:pharmacology; D018030:Silver Compounds / Q000737:chemistry* / Q000494:pharmacology*; D014508:Urea / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D010087:Oxides; D018030:Silver Compounds; D010649:Phenylalanine; D006046:Gold; C040225:disilver oxide; D014508:Urea; D000469:Alkaline Phosphatase