1ht2
From Proteopedia
| Line 29: | Line 29: | ||
</div> | </div> | ||
<div class="pdbe-citations 1ht2" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 1ht2" style="background-color:#fffaf0;"></div> | ||
| + | |||
| + | ==See Also== | ||
| + | *[[Heat Shock Proteins|Heat Shock Proteins]] | ||
== References == | == References == | ||
<references/> | <references/> | ||
Revision as of 05:41, 30 May 2018
Nucleotide-Dependent Conformational Changes in a Protease-Associated ATPase HslU
Structural highlights
Function[HSLV_ECOLI] Protease subunit of a proteasome-like degradation complex believed to be a general protein degrading machinery. The complex has been shown to be involved in the specific degradation of heat shock induced transcription factors such as RpoH and SulA. In addition, small hydrophobic peptides are also hydrolyzed by HslV. HslV has weak protease activity even in the absence of HslU, but this activity is induced more than 100-fold in the presence of HslU. HslU recognizes protein substrates and unfolds these before guiding them to HslV for hydrolysis. HslV is not believed to degrade folded proteins.[1] [2] [3] [4] [5] [6] [7] [HSLU_ECOLI] ATPase subunit of a proteasome-like degradation complex; this subunit has chaperone activity. The binding of ATP and its subsequent hydrolysis by HslU are essential for unfolding of protein substrates subsequently hydrolyzed by HslV. HslU recognizes the N-terminal part of its protein substrates and unfolds these before they are guided to HslV for hydrolysis.[8] [9] [10] [11] [12] [13] [14] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedBACKGROUND: The bacterial heat shock locus ATPase HslU is an AAA(+) protein that has structures known in many nucleotide-free and -bound states. Nucleotide is required for the formation of the biologically active HslU hexameric assembly. The hexameric HslU ATPase binds the dodecameric HslV peptidase and forms an ATP-dependent HslVU protease. RESULTS: We have characterized four distinct HslU conformational states, going sequentially from open to closed: the empty, SO(4), ATP, and ADP states. The nucleotide binds at a cleft formed by an alpha/beta domain and an alpha-helical domain in HslU. The four HslU states differ by a rotation of the alpha-helical domain. This classification leads to a correction of nucleotide identity in one structure and reveals the ATP hydrolysis-dependent structural changes in the HslVU complex, including a ring rotation and a conformational change of the HslU C terminus. This leads to an amended protein unfolding-coupled translocation mechanism. CONCLUSIONS: The observed nucleotide-dependent conformational changes in HslU and their governing principles provide a framework for the mechanistic understanding of other AAA(+) proteins. Nucleotide-dependent conformational changes in a protease-associated ATPase HsIU.,Wang J, Song JJ, Seong IS, Franklin MC, Kamtekar S, Eom SH, Chung CH Structure. 2001 Nov;9(11):1107-16. PMID:11709174[15] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
Categories: Ecobd | Chung, C H | Eom, S H | Franklin, M C | Kamtekar, S | Seong, I S | Song, J J | Wang, J | Chaperone | Hslvu | Peptidase-atpase complex
