Methyl motions in13C-methylated concanavalin as studied by13C magnetic resonance relaxation techniques

A. D. Sherry, J. Keepers, T. L. James, J. Teherani

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The carbon-13 spin-lattice relaxation times and nuclear Overhauser enhancements of the N-monomethyllysine, N,N-dimethyllysine, and Nα,Nα-dimethylalanine resonances of 13C-methylated concanavalin A have been measured at three carbon frequencies and compared to the relaxation parameters predicted by several motional models. The experimental parameters cannot be reproduced by a simple dipolar relaxation model which includes isotropic reorientation of the protein plus free internal rotational diffusion of the methyl groups but are well predicted by a wobble in a cone model which includes isotropic reorientation of the protein at 33 ns, free internal rotational diffusion of the methyl groups, and a wobble diffusion which reflects the net motion of the amino acid side chains. The analysis indicates that the methylated ∈-amino side chains exhibit only slightly more motional freedom than does the methylated N-terminal α-amino group and suggests some restriction of methyl group rotation in the dimethylamino residues.

Original languageEnglish (US)
Pages (from-to)3181-3185
Number of pages5
JournalBiochemistry
Volume23
Issue number14
StatePublished - 1984

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Relaxation Therapy
Magnetic resonance
Magnetic Resonance Spectroscopy
Carbon
Spin-lattice relaxation
Concanavalin A
Relaxation time
Cones
Proteins
Amino Acids

ASJC Scopus subject areas

  • Biochemistry

Cite this

Methyl motions in13C-methylated concanavalin as studied by13C magnetic resonance relaxation techniques. / Sherry, A. D.; Keepers, J.; James, T. L.; Teherani, J.

In: Biochemistry, Vol. 23, No. 14, 1984, p. 3181-3185.

Research output: Contribution to journalArticle

Sherry, A. D. ; Keepers, J. ; James, T. L. ; Teherani, J. / Methyl motions in13C-methylated concanavalin as studied by13C magnetic resonance relaxation techniques. In: Biochemistry. 1984 ; Vol. 23, No. 14. pp. 3181-3185.
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