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Specific labeling of threonine methyl groups for NMR studies of protein-nucleic acid complexes.

ABSTRACT: Specific (13)C labeling of Thr methyl groups has been accomplished via the growth of a standard laboratory strain of Escherichia coli on [2-(13)C]glycerol in the presence of deuterated isoketovalerate, Ile, and Ala. Diversion of the label from the Thr biosynthetic pathway is suppressed by including Lys, Met, and Ile in the growth medium. This method complements the repertoire of methyl labeling schemes for NMR structural and dynamic studies of proteins and is particularly useful for the study of nucleic acid binding proteins because of the high propensity of Thr residues at protein-DNA and -RNA interfaces.

SUBMITTER: Sinha K

PROVIDER: S-EPMC3222749 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Specific labeling of threonine methyl groups for NMR studies of protein-nucleic acid complexes.

Sinha Kaustubh K Jen-Jacobson Linda L Rule Gordon S GS

Biochemistry 20111103 47

Specific (13)C labeling of Thr methyl groups has been accomplished via the growth of a standard laboratory strain of Escherichia coli on [2-(13)C]glycerol in the presence of deuterated isoketovalerate, Ile, and Ala. Diversion of the label from the Thr biosynthetic pathway is suppressed by including Lys, Met, and Ile in the growth medium. This method complements the repertoire of methyl labeling schemes for NMR structural and dynamic studies of proteins and is particularly useful for the study of ...[more]

PMID: 22039762

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