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One-sample approach to determine the relative orientations of proteins in ternary and binary complexes from residual dipolar coupling measurements.

ABSTRACT: We present a procedure that supports the acquisition of (1)H-(15)N residual dipolar coupling (RDC) values for individual subunits in binary or ternary protein assemblies from a single experimental sample. Our method relies on asymmetric labeling of each subunit with the following scheme: species A uniformly with (15)N, species B uniformly with (15)N and (13)C, and species C uniformly with (15)N but selectively with (13)C' or (13)C(alpha). Because only a single sample is required, the approach obviates the need for preparing multiple samples and eliminates potential errors introduced from differences in sample conditions. Because numerous biological processes rely on protein assemblies or transient interactions, this method should be well suited for a wide range of future applications.

SUBMITTER: Tonelli M

PROVIDER: S-EPMC3061545 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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One-sample approach to determine the relative orientations of proteins in ternary and binary complexes from residual dipolar coupling measurements.

Tonelli Marco M Masterson Larry R LR Cornilescu Gabriel G Markley John L JL Veglia Gianluigi G

Journal of the American Chemical Society 20091001 40

We present a procedure that supports the acquisition of (1)H-(15)N residual dipolar coupling (RDC) values for individual subunits in binary or ternary protein assemblies from a single experimental sample. Our method relies on asymmetric labeling of each subunit with the following scheme: species A uniformly with (15)N, species B uniformly with (15)N and (13)C, and species C uniformly with (15)N but selectively with (13)C' or (13)C(alpha). Because only a single sample is required, the approach ob ...[more]

PMID: 19764746

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