Heat activates the AAA+ HslUV protease by melting an axial autoinhibitory plug.
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ABSTRACT:
SUBMITTER: Baytshtok V
PROVIDER: S-EPMC7849044 | biostudies-literature | 2021 Jan
REPOSITORIES: biostudies-literature
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Heat activates the AAA+ HslUV protease by melting an axial autoinhibitory plug.
Baytshtok Vladimir V Fei Xue X Shih Tsai-Ting TT Grant Robert A RA Santos Justin C JC Baker Tania A TA Sauer Robert T RT
Cell reports 20210101 3
At low temperatures, protein degradation by the AAA+ HslUV protease is very slow. New crystal structures reveal that residues in the intermediate domain of the HslU<sub>6</sub> unfoldase can plug its axial channel, blocking productive substrate binding and subsequent unfolding, translocation, and degradation by the HslV<sub>12</sub> peptidase. Biochemical experiments with wild-type and mutant enzymes support a model in which heat-induced melting of this autoinhibitory plug activates HslUV proteo ...[more]
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