Interaction of SecB with soluble SecA

FEBS Letters

Driessen, Arnold J.M¹  Lakowicz, Joseph R²  den Blaauwen, Tanneke¹  Terpetschnig, Ewald² 

[1] Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands;Center for Fluorescence Spectroscopy, Department of Biological Chemistry, University of Maryland at Baltimore School of Medicine, Baltimore, MD 21201, USA

关键词: Anisotropy;    Preprotein targeting;    SecA;    SecB;    BSA;    bovine serum albumin;    DLS;    dynamic light scattering;    DTT;    dithiothreitol;    Ru(bpy)2(dcbpy);    Ru bis(2;    2′-bipyridine)(2;    2′-bipyridine-4;    4′-dicarboxylIC acid);   

DOI  :  10.1016/S0014-5793(97)01142-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The preprotein binding molecular chaperone SecB functions by preventing the premature folding of the preprotein in the cytosol, and targeting it to the peripheral subunit SecA of the translocase at the cytoplasmic membrane. The nature of the interaction of SecB with soluble SecA was studied by fluorescence anisotropy spectroscopy of Ru(bpy)₂(dcbpy)-labeled SecA in the presence of increasing concentrations of SecB. A more than 50-fold difference in affinity for the cytosolic SecA compared to translocase associated SecA seems to prevent unproductive binding of SecB to the cytosolic SecA and stresses its targeting function.

【 授权许可】

Unknown