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Site-specific labeling of proteins for electron microscopy.

ABSTRACT: Electron microscopy is commonly employed to determine the subunit organization of large macromolecular assemblies. However, the field lacks a robust molecular labeling methodology for unambiguous identification of constituent subunits. We present a strategy that exploits the unique properties of an unnatural amino acid in order to enable site-specific attachment of a single, readily identifiable protein label at any solvent-exposed position on the macromolecular surface. Using this method, we show clear labeling of a subunit within the 26S proteasome lid subcomplex that has not been amenable to labeling by traditional approaches.

SUBMITTER: Dambacher CM

PROVIDER: S-EPMC4633364 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Site-specific labeling of proteins for electron microscopy.

Dambacher Corey M CM Lander Gabriel C GC

Journal of structural biology 20150925 2

Electron microscopy is commonly employed to determine the subunit organization of large macromolecular assemblies. However, the field lacks a robust molecular labeling methodology for unambiguous identification of constituent subunits. We present a strategy that exploits the unique properties of an unnatural amino acid in order to enable site-specific attachment of a single, readily identifiable protein label at any solvent-exposed position on the macromolecular surface. Using this method, we sh ...[more]

PMID: 26409249

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