A 13C labeling strategy reveals a range of aromatic side chain motion in calmodulin.
J Am Chem Soc
; 135(26): 9560-3, 2013 Jul 03.
Article
in En
| MEDLINE
| ID: mdl-23767407
ABSTRACT
NMR relaxation experiments often require site-specific isotopic enrichment schemes in order to allow for quantitative interpretation. Here we describe a new labeling scheme for site-specific (13)C-(1)H enrichment of a single ortho position of aromatic amino acid side chains in an otherwise perdeuterated background by employing a combination of [4-(13)C]erythrose and deuterated pyruvate during growth on deuterium oxide. This labeling scheme largely eliminates undesired contributions to (13)C relaxation and greatly simplifies the fitting of relaxation data using the Lipari-Szabo model-free formalism. This approach is illustrated with calcium-saturated vertebrate calmodulin and oxidized flavodoxin from Cyanobacterium anabaena . Analysis of (13)C relaxation in the aromatic groups of calcium-saturated calmodulin indicates a wide range of motion in the subnanosecond time regime.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Calmodulin
/
Hydrocarbons, Aromatic
Type of study:
Prognostic_studies
Language:
En
Journal:
J Am Chem Soc
Year:
2013
Document type:
Article
Affiliation country:
United States
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA