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A prochelator peptide designed to use heterometallic cooperativity to enhance metal ion affinity.

ABSTRACT: A peptide has been designed so that its chelating affinity for one type of metal ion regulates its affinity for a second, different type of metal ion. The prochelator peptide (PCP), which is a fusion of motifs evocative of calcium loops and zinc fingers, forms a 1?:?2 Zn?:?peptide complex at pH 7.4 that increases its affinity for Zn2+ ?3-fold in the presence of Tb3+ (log??2 from 13.8 to 14.3), while the 1?:?1 luminescent complex with Tb3+ is brighter, longer lived, and 20-fold tighter in the presence of Zn2+ (log?K from 6.2 to 7.5). This unique example of cooperative, heterometallic allostery in a biologically compatible construct suggests the possibility of designing conditionally active metal-binding agents that could respond to dynamic changes in cellular metal status.

SUBMITTER: Alies B

PROVIDER: S-EPMC5659173 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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A prochelator peptide designed to use heterometallic cooperativity to enhance metal ion affinity.

Alies Bruno B Wiener Jacob D JD Franz Katherine J KJ

Chemical science 20150505 6

A peptide has been designed so that its chelating affinity for one type of metal ion regulates its affinity for a second, different type of metal ion. The prochelator peptide (PCP), which is a fusion of motifs evocative of calcium loops and zinc fingers, forms a 1 : 2 Zn : peptide complex at pH 7.4 that increases its affinity for Zn2+ ∼3-fold in the presence of Tb3+ (log β2 from 13.8 to 14.3), while the 1 : 1 luminescent complex with Tb3+ is bri ...[more]

PMID: 29511523

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