Allosteric inhibition of a-thrombin enzymatic activity with ultrasmall gold nanoparticles

The catalytic activity of enzymes can be regulated by interactions with synthetic nanoparticles (NPs) in a number of ways. To date, however, the potential use of NPs as allosteric effectors has not been investigated in detail. Importantly, targeting allosteric (distal) sites on the enzyme surface co...

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Detalles Bibliográficos
Autores: Lira, André [UNIFESP], Ferreira, Rodrigo [UNIFESP], Torquato, Ricardo [UNIFESP], Oliva, Maria L.V. [UNIFESP], Schuck, Peter, Sousa, Alioscka A [UNIFESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Federal de São Paulo (UNIFESP)
Repositorio:Repositório Institucional da UNIFESP
Idioma:inglés
OAI Identifier:oai:repositorio.unifesp.br:11600/61044
Acceso en línea:https://pubs.rsc.org/en/content/articlelanding/2019/na/c8na00081f#!divAbstract
https://repositorio.unifesp.br/handle/11600/61044
Access Level:acceso abierto
Palabra clave:Ultrasmall nanoparticles
Enzyme inhibition
Descripción
Sumario:The catalytic activity of enzymes can be regulated by interactions with synthetic nanoparticles (NPs) in a number of ways. To date, however, the potential use of NPs as allosteric effectors has not been investigated in detail. Importantly, targeting allosteric (distal) sites on the enzyme surface could afford unique ways to modulate the activity, allowing for either enzyme activation, partial or full inhibition. Using p-mercaptobenzoic acid-coated ultrasmall gold NPs (AuMBA) and human a-thrombin as a model system, here we experimentally tested the hypothesis that enzyme activity could be regulated through ultrasmall NP interactions at allosteric sites. We show that AuMBA interacted selectively and reversibly around two positively charged regions of the thrombin surface (exosites 1 and 2) and away from the active site. NP complexation at the exosites transmitted long-range structural changes over to the active site, altering both substrate binding affinity and catalysis. Significantly, thrombin activity was partially reduced – but not completely inhibited – by interactions with AuMBA. These findings indicate that interactions of proteins with ultrasmall NPs may mimic a typical biomolecular complexation event, and suggest the prospect of using ultrasmall particles as synthetic receptors to allosterically regulate protein function