title: Reversible regulation of chymotrypsin activity using negatively charged gold nanoparticles featuring malonic acid termini.
abstract: Negatively charged gold nanoparticles featuring 2-(10-mercapto-decyl)-malonic acid were synthesized using the Murray place-displacement reaction. These water-soluble malonate gold mixed monolayer protected clusters (MMPCs) effectively bind and inhibit chymotrypsin based on complementary electrostatic surface recognition. The effect of increasing ionic strength on inhibition was also studied. It was observed that addition of high ionic strength solutions to protein-nanoparticle complexes show almost complete restoration of protein activity. The conformational change of chymotrypsin upon binding to the MMPC was investigated using fluorescence spectrometry and circular dichroism, thus correlating structural changes with enzyme activity.
authors.affiliation: Department of Chemistry, Program in Molecular and Cell Biology, 710 North Pleasant St., University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Simard
authors.forename: Beth
authors.initials: B
authors.lastname: Szymanski
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Rotello
mesh_terms: D000818:Animals; D000838:Anions / Q000737:chemistry; D001665:Binding Sites; D002417:Cattle; D002918:Chymotrypsin / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D002942:Circular Dichroism / Q000379:methods; D006046:Gold / Q000737:chemistry*; D008314:Malonates / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D009994:Osmolar Concentration; D010179:Pancreas / Q000201:enzymology; D012680:Sensitivity and Specificity; D012995:Solubility; D013050:Spectrometry, Fluorescence / Q000379:methods; D055672:Static Electricity; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: C512410:2-(10-mercaptodecyl)malonic acid; D000838:Anions; D008314:Malonates; D013438:Sulfhydryl Compounds; D014867:Water; D006046:Gold; D002918:Chymotrypsin