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In Cellulo Mossbauer and EPR Studies Bring New Evidence to the Long-Standing Debate on Iron-Sulfur Cluster Binding in Human Anamorsin.

ABSTRACT: Human anamorsin is an iron-sulfur (Fe-S)-cluster-binding protein acting as an electron donor in the early steps of cytosolic iron-sulfur protein biogenesis. Human anamorsin belongs to the eukaryotic CIAPIN1 protein family and contains two highly conserved cysteine-rich motifs, each binding an Fe-S cluster. In vitro works by various groups have provided rather controversial results for the type of Fe-S clusters bound to the CIAPIN1 proteins. In order to unravel the knot on this topic, we used an in cellulo approach combining Mössbauer and EPR spectroscopies to characterize the iron-sulfur-cluster-bound form of human anamorsin. We found that the protein binds two [2Fe-2S] clusters at both its cysteine-rich motifs.

SUBMITTER: Matteucci S

PROVIDER: S-EPMC8251831 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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In Cellulo Mössbauer and EPR Studies Bring New Evidence to the Long-Standing Debate on Iron-Sulfur Cluster Binding in Human Anamorsin.

Matteucci Sara S Camponeschi Francesca F Clémancey Martin M Ciofi-Baffoni Simone S Blondin Geneviève G Banci Lucia L

Angewandte Chemie (International ed. in English) 20210524 27

Human anamorsin is an iron-sulfur (Fe-S)-cluster-binding protein acting as an electron donor in the early steps of cytosolic iron-sulfur protein biogenesis. Human anamorsin belongs to the eukaryotic CIAPIN1 protein family and contains two highly conserved cysteine-rich motifs, each binding an Fe-S cluster. In vitro works by various groups have provided rather controversial results for the type of Fe-S clusters bound to the CIAPIN1 proteins. In order to unravel the knot on this topic, we used an ...[more]

PMID: 33852169

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