Send to

Choose Destination
Structure. 2005 Apr;13(4):579-90.

Structures of the N-terminal and middle domains of E. coli Hsp90 and conformation changes upon ADP binding.

Author information

Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, North Carolina 27599, USA.


Hsp90 is an abundant molecular chaperone involved in many biological systems. We report here the crystal structures of the unliganded and ADP bound fragments containing the N-terminal and middle domains of HtpG, an E. coli Hsp90. These domains are not connected through a flexible linker, as often portrayed in models, but are intimately associated with one another. The individual HtpG domains have similar folding to those of DNA gyrase B but assemble differently, suggesting somewhat different mechanisms for the ATPase superfamily. ADP binds to a subpocket of a large site that is jointly formed by the N-terminal and middle domains and induces conformational changes of the N-terminal domain. We speculate that this large pocket serves as a putative site for binding of client proteins/cochaperones. Modeling shows that ATP is not exposed to the molecular surface, thus implying that ATP activation of hsp90 chaperone activities is accomplished via conformational changes.

Comment in

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center