Crystallization of a pentapeptide-repeat protein by reductive cyclic pentylation of free amines with glutaraldehyde.
Acta Crystallogr D Biol Crystallogr
; 65(Pt 5): 462-9, 2009 May.
Article
em En
| MEDLINE
| ID: mdl-19390151
ABSTRACT
The pentapeptide-repeat protein EfsQnr from Enterococcus faecalis protects DNA gyrase from inhibition by fluoroquinolones. EfsQnr was cloned and purified to homogeneity, but failed to produce diffraction-quality crystals in initial crystallization screens. Treatment of EfsQnr with glutaraldehyde and the strong reducing agent borane-dimethylamine resulted in a derivatized protein which produced crystals that diffracted to 1.6 A resolution; their structure was subsequently determined by single-wavelength anomalous dispersion. Analysis of the derivatized protein using Fourier transform ion cyclotron resonance mass spectrometry indicated a mass increase of 68 Da per free amino group. Electron-density maps about a limited number of structurally ordered lysines indicated that the modification was a cyclic pentylation of free amines, producing piperidine groups.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Glutaral
/
Enterococcus faecalis
/
Reagentes de Ligações Cruzadas
Limite:
Humans
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article