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Avidity for Polypeptide Binding by Nucleotide-Bound Hsp104 Structures.

ABSTRACT: Recent Hsp104 structural studies have reported both planar and helical models of the hexameric structure. The conformation of Hsp104 monomers within the hexamer is affected by nucleotide ligation. After nucleotide-driven hexamer formation, Hsp104-catalyzed disruption of protein aggregates requires binding to the peptide substrate. Here, we examine the oligomeric state of Hsp104 and its peptide binding competency in the absence of nucleotide and in the presence of ADP, ATP?S, AMPPNP, or AMPPCP. Surprisingly, we found that only ATP?S facilitates avid peptide binding by Hsp104. We propose that the modulation between high- and low-peptide affinity states observed with these ATP analogues is an important component of the disaggregation mechanism of Hsp104.

SUBMITTER: Weaver CL

PROVIDER: S-EPMC5649362 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Avidity for Polypeptide Binding by Nucleotide-Bound Hsp104 Structures.

Weaver Clarissa L CL Duran Elizabeth C EC Mack Korrie L KL Lin JiaBei J Jackrel Meredith E ME Sweeny Elizabeth A EA Shorter James J Lucius Aaron L AL

Biochemistry 20170410 15

Recent Hsp104 structural studies have reported both planar and helical models of the hexameric structure. The conformation of Hsp104 monomers within the hexamer is affected by nucleotide ligation. After nucleotide-driven hexamer formation, Hsp104-catalyzed disruption of protein aggregates requires binding to the peptide substrate. Here, we examine the oligomeric state of Hsp104 and its peptide binding competency in the absence of nucleotide and in the presence of ADP, ATPγS, AMPPNP, or AMPPCP. S ...[more]

PMID: 28379007

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