Structural study of the partially disordered full-length δ subunit of RNA polymerase from Bacillus subtilis.
Chembiochem
; 14(14): 1772-9, 2013 Sep 23.
Article
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| MEDLINE
| ID: mdl-23868186
ABSTRACT
The partially disordered δ subunit of RNA polymerase was studied by various NMR techniques. The structure of the well-folded N-terminal domain was determined based on inter-proton distances in NOESY spectra. The obtained structural model was compared to the previously determined structure of a truncated construct (lacking the C-terminal domain). Only marginal differences were identified, thus indicating that the first structural model was not significantly compromised by the absence of the C-terminal domain. Various (15) N relaxation experiments were employed to describe the flexibility of both domains. The relaxation data revealed that the C-terminal domain is more flexible, but its flexibility is not uniform. By using paramagnetic labels, transient contacts of the C-terminal tail with the N-terminal domain and with itself were identified. A propensity of the C-terminal domain to form ß-type structures was obtained by chemical shift analysis. Comparison with the paramagnetic relaxation enhancement indicated a well-balanced interplay of repulsive and attractive electrostatic interactions governing the conformational behavior of the C-terminal domain. The results showed that the δ subunit consists of a well-ordered N-terminal domain and a flexible C-terminal domain that exhibits a complex hierarchy of partial ordering.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Bacillus subtilis
/
ARN Polimerasas Dirigidas por ADN
Idioma:
En
Revista:
Chembiochem
Asunto de la revista:
BIOQUIMICA
Año:
2013
Tipo del documento:
Article