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 == Publication Abstract from PubMed ==
-BACKGROUND: The bacterial heat shock locus HslU ATPase and HslV peptidase together form an ATP-dependent HslVU protease. Bacterial HslVU is a homolog of the eukaryotic 26S proteasome. Crystallographic studies of HslVU should provide an understanding of ATP-dependent protein unfolding, translocation, and proteolysis by this and other ATP-dependent proteases. RESULTS: We present a 3.0 A resolution crystal structure of HslVU with an HslU hexamer bound at one end of an HslV dodecamer. The structure shows that the central pores of the ATPase and peptidase are next to each other and aligned. The central pore of HslU consists of a GYVG motif, which is conserved among protease-associated ATPases. The binding of one HslU hexamer to one end of an HslV dodecamer in the 3.0 A resolution structure opens both HslV central pores and induces asymmetric changes in HslV. CONCLUSIONS: Analysis of nucleotide binding induced conformational changes in the current and previous HslU structures suggests a protein unfolding-coupled translocation mechanism. In this mechanism, unfolded polypeptides are threaded through the aligned pores of the ATPase and peptidase and translocated into the peptidase central chamber.
+The I domain of HslU sits above the AAA+ ring and forms a funnel-like entry to the axial pore, where protein substrates are engaged, unfolded, and translocated into HslV for degradation. The L199Q I-domain substitution, which was originally reported as a loss-of-function mutation, resides in a segment that appears to adopt multiple conformations as electron density is not observed in HslU and HslUV crystal structures. The L199Q sequence change does not alter the structure of the AAA+ ring or its interactions with HslV but increases I-domain susceptibility to limited endoproteolysis. Notably, the L199Q mutation increases the rate of ATP hydrolysis substantially, results in slower degradation of some proteins but faster degradation of other substrates, and markedly changes the preference of HslUV for initiating degradation at the N or C terminus of model substrates. Thus, a structurally dynamic region of the I domain plays a key role in controlling protein degradation by HslUV.
-Crystal structures of the HslVU peptidase-ATPase complex reveal an ATP-dependent proteolysis mechanism.,Wang J, Song JJ, Franklin MC, Kamtekar S, Im YJ, Rho SH, Seong IS, Lee CS, Chung CH, Eom SH Structure. 2001 Feb 7;9(2):177-84. PMID:11250202<ref>PMID:11250202</ref>
+A Structurally Dynamic Region of the HslU Intermediate Domain Controls Protein Degradation and ATP Hydrolysis.,Baytshtok V, Fei X, Grant RA, Baker TA, Sauer RT Structure. 2016 Oct 4;24(10):1766-1777. doi: 10.1016/j.str.2016.08.012. Epub 2016, Sep 22. PMID:27667691<ref>PMID:27667691</ref>
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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+==See Also==
+*[[ATPase|ATPase]]
+*[[Heat Shock Proteins|Heat Shock Proteins]]
 == References ==
 <references/>