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Electron paramagnetic spectrum of dimanganic human serum transferrin.

ABSTRACT: An EPR signal for Mn(III) bound to the metal transport protein transferrin has been detected for the first time. The temperature dependence and simulations of the EPR signal are consistent with the Mn(III) centers being six-coordinate in an elongated tetragonal environment. Thus, the incorporation of Mn(III) within the Tf active site does not vastly alter the coordination number or active site geometry relative to native Fe(III)₂-Tf. This parallel mode EPR signal for Mn(III)₂-Tf could prove valuable for future studies aimed at determining the physiological relevance of Mn(III)₂-Tf.

SUBMITTER: Lockart MM

PROVIDER: S-EPMC10077959 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Electron paramagnetic spectrum of dimanganic human serum transferrin.

Lockart Molly M MM Edwards Kyle C KC Vincent John B JB Pierce Brad S BS

Polyhedron 20210418

An EPR signal for Mn(III) bound to the metal transport protein transferrin has been detected for the first time. The temperature dependence and simulations of the EPR signal are consistent with the Mn(III) centers being six-coordinate in an elongated tetragonal environment. Thus, the incorporation of Mn(III) within the Tf active site does not vastly alter the coordination number or active site geometry relative to native Fe(III)<sub>2</sub>-Tf. This parallel mode EPR signal for Mn(III)<sub>2</su ...[more]

PMID: 37034105

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