Ultracentrifugal analysis of the quaternary structure of the raf represser from Escherichia coli

FEBS Letters

Aslanidis, Charalampos¹  Jaenicke, Rainer²  Muiznieks, Indrikis¹  Schmitt, Rüdiger¹ 

[1] Institut für Biochemie, Genetik und Mikrobiologie, Universität Regensburg, D-8400 Regensburg, FRG;Institut für Biophysik und Physikalische Biochemie, Universität Regensburg, D-8400 Regensburg, FRG

关键词: Analytical ultracentrifugation;    Dissociation-association;    Quaternary structure;    Represser;    raf;    Sedimentation analysis;   

DOI  :  10.1016/0014-5793(90)80111-U

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The raf repressor from Escherichia coli regulates the expression of the plasmid-borne raf operon by switching between active and inactive conformational states. Ultracentrifugal analysis of the largely purified repressor proves the DNA-free protein to undergo concentration-dependent dissociation-association. High-speed sedimentation equilibria show that the 72 kDa dimer prevails under meniscus depletion conditions. At intracellular concentrations the 144 kDa dimer-of-dimers is the dominating species. It is suggested that the tetrameric structure of the raf repressor is involved in the recognition of the 18-basepair operator DNA.

【 授权许可】

Unknown