TEM and STEM-EDS evaluation of metal nanoparticle encapsulation in GroEL/GroES complexes according to the reaction mechanism of chaperonin

© The Author(s) 2020. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissionsoup.com..

Escherichia coli chaperonin GroEL, which is a large cylindrical protein complex comprising two heptameric rings with cavities of 4.5 nm each in the center, assists in intracellular protein folding with the aid of GroES and adenosine triphosphate (ATP). Here, we investigated the possibility that GroEL can also encapsulate metal nanoparticles (NPs) up to ∼5 nm in diameter into the cavities with the aid of GroES and ATP. The slow ATP-hydrolyzing GroELD52A/D398A mutant, which forms extremely stable complexes with GroES (half-time of ∼6 days), made it possible to analyze GroEL/GroES complexes containing metal NPs. Scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy analysis proved distinctly that FePt NPs and Au NPs were encapsulated in the GroEL/GroES complexes. Dynamic light scattering measurements showed that the NPs in the GroEL/GroES complex were able to maintain their dispersibility in solution. We previously described that the incubation of GroEL and GroES in the presence of ATP·BeFx and adenosine diphosphate·BeFx resulted in the formation of symmetric football-shaped and asymmetric bullet-shaped complexes, respectively. Based on this knowledge, we successfully constructed the football-shaped complex in which two compartments were occupied by Pt or Au NPs (first compartment) and FePt NPs (second compartment). This study showed that metal NPs were sequentially encapsulated according to the GroEL reaction in a step-by-step manner. In light of these results, chaperonin can be used as a tool for handling nanomaterials.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:70

Enthalten in:

Microscopy (Oxford, England) - 70(2021), 3 vom: 06. Juni, Seite 289-296

Sprache:

Englisch

Beteiligte Personen:

Yoda, Hiromi [VerfasserIn]
Koike-Takeshita, Ayumi [VerfasserIn]

Links:

Volltext

Themen:

49DFR088MY
7440-57-5
8L70Q75FXE
Adenosine Triphosphate
Chaperonin
Chaperonin 10
Chaperonin 60
Chaperonins
E1UOL152H7
EC 3.6.1.-
Escherichia coli Proteins
Gold
GroEL
Iron
Journal Article
Metal nanoparticle
Multiprotein Complexes
Platinum
STEM-EDS
TEM

Anmerkungen:

Date Completed 14.10.2021

Date Revised 14.10.2021

published: Print

Citation Status MEDLINE

doi:

10.1093/jmicro/dfaa064

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM317415913