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Functionalization of the BCL6 BTB domain into a noncovalent crystallization chaperone.

ABSTRACT: The production of diffraction-quality protein crystals is challenging and often requires bespoke, time-consuming and expensive strategies. A system has been developed in which the BCL6 BTB domain acts as a crystallization chaperone and promiscuous assembly block that may form the basis for affinity-capture crystallography. The protein of interest is expressed with a C-terminal tag that interacts with the BTB domain, and co-crystallization leads to its incorporation within a BTB-domain lattice. This strategy was used to solve the structure of the SH3 domain of human nebulin, a structure previously solved by NMR, at 1.56?Å resolution. This approach is simple and effective, requiring only routine protein complexation and crystallization screening, and should be applicable to a range of proteins.

SUBMITTER: Zacharchenko T

PROVIDER: S-EPMC7924223 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Functionalization of the BCL6 BTB domain into a noncovalent crystallization chaperone.

Zacharchenko Thomas T Wright Stephanie S

IUCrJ 20210111 Pt 2

The production of diffraction-quality protein crystals is challenging and often requires bespoke, time-consuming and expensive strategies. A system has been developed in which the BCL6 BTB domain acts as a crystallization chaperone and promiscuous assembly block that may form the basis for affinity-capture crystallography. The protein of interest is expressed with a C-terminal tag that interacts with the BTB domain, and co-crystallization leads to its incorporation within a BTB-domain lattice. T ...[more]

PMID: 33708392

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