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Positive allostery in metal ion binding by a cooperatively folded ?-peptide bundle.

ABSTRACT: Metal ion binding is exploited by proteins in nature to catalyze reactions, bind molecules, and favor discrete structures, but it has not been demonstrated in ?-peptides or their assemblies. Here we report the design, synthesis, and characterization of a ?-peptide bundle that uniquely binds two Cd(II) ions in a distinct bicoordinate array. The two Cd(II) ions bind with positive allosteric cooperativity and increase the thermodynamic stability of the bundle by more than 50 °C. This system provides a unique, synthetic context to explore allosteric regulation and should pave the way to sophisticated molecular assemblies with catalytic and substrate-sensing functions that have historically not been available to de novo designed synthetic proteomimetics in water.

SUBMITTER: Miller JP

PROVIDER: S-EPMC4210112 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Positive allostery in metal ion binding by a cooperatively folded β-peptide bundle.

Miller Jonathan P JP Melicher Michael S MS Schepartz Alanna A

Journal of the American Chemical Society 20141007 42

Metal ion binding is exploited by proteins in nature to catalyze reactions, bind molecules, and favor discrete structures, but it has not been demonstrated in β-peptides or their assemblies. Here we report the design, synthesis, and characterization of a β-peptide bundle that uniquely binds two Cd(II) ions in a distinct bicoordinate array. The two Cd(II) ions bind with positive allosteric cooperativity and increase the thermodynamic stability of the bundle by more than 50 °C. This system provide ...[more]

PMID: 25290247

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