PMID:10049803
| Citation |
Wang, J, Hartling, JA and Flanagan, JM (1998) Crystal structure determination of Escherichia coli ClpP starting from an EM-derived mask. J. Struct. Biol. 124:151-63 |
|---|---|
| Abstract |
Large ATP-dependent proteolytic complexes carry out the majority of intracellular proteolysis. To begin to understand the function of these proteases at a structural level, we have combined the information from a number of biophysical techniques such as electron microscopy (EM), small-angle scattering, and x-ray crystallography. In this study, we exploited the inherent symmetry of Escherichia coli ClpP, the proteolytic component of the ClpAP/XP ATP-dependent protease, to determine its x-ray crystal structure to 2.3-A resolution starting with a phase set derived from a low-resolution mask obtained from EM and small-angle x-ray scattering analysis. Sevenfold and 14-fold noncrystallographic symmetry averaging facilitated phase extension beyond 20 A and in combination with mask redetermination and matrix refinement was sufficient for completely determining the structure. The structure of ClpP is a homo-tetradecamer composed of two heptameric rings enclosing a cavity of approximately 50 A in diameter that compartmentalizes the 14 serine proteolytic active sites. Comparison of the ClpP structure with those of the 20S proteasome and HslV reveals a striking example of evolutionary convergence, despite them being unrelated in sequence and fold. Moreover, similarity in their overall architecture suggests a common model for their action. |
| Links |
PubMed Online version:10.1006/jsbi.1998.4058 |
| Keywords |
Adenosine Triphosphatases/chemistry; Adenosine Triphosphatases/metabolism; Adenosine Triphosphatases/ultrastructure; Adenosine Triphosphate/metabolism; Crystallography, X-Ray/methods; Endopeptidase Clp; Escherichia coli/enzymology; Macromolecular Substances; Microscopy, Electron/methods; Models, Molecular; Protein Structure, Secondary; Serine Endopeptidases/chemistry; Serine Endopeptidases/metabolism; Serine Endopeptidases/ultrastructure; Software |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.