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Protein labeling and crosslinking by covalent aptamers.

ABSTRACT: In this chapter, a new approach to the selective modification of native proteins is discussed, using electrophilic covalent aptamers. These biochemical tools are generated through the site-specific incorporation of a label-transferring or crosslinking electrophile into a DNA aptamer. Covalent aptamers provide the ability to transfer a variety of functional handles to a protein of interest or to irreversibly crosslink to the target. Methods for the aptamer-mediated labeling and crosslinking of thrombin are described. Thrombin labeling is fast and selective, in both simple buffer and in human plasma and outcompetes nuclease-mediated degradation. This approach provides facile, sensitive detection of labeled protein by western blot, SDS-PAGE, and mass spectrometry.

SUBMITTER: Cacace M

PROVIDER: S-EPMC10725707 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Protein labeling and crosslinking by covalent aptamers.

Cacace Mary M Tivon Yaniv Y Deiters Alexander A

Methods in enzymology 20221224

In this chapter, a new approach to the selective modification of native proteins is discussed, using electrophilic covalent aptamers. These biochemical tools are generated through the site-specific incorporation of a label-transferring or crosslinking electrophile into a DNA aptamer. Covalent aptamers provide the ability to transfer a variety of functional handles to a protein of interest or to irreversibly crosslink to the target. Methods for the aptamer-mediated labeling and crosslinking of th ...[more]

PMID: 36948709

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