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Revisiting the concept of peptide bond planarity in an iron-sulfur protein by neutron structure analysis.

ABSTRACT: The planarity of the peptide bond is important for the stability and structure formation of proteins. However, substantial distortion of peptide bonds has been reported in several high-resolution structures and computational analyses. To investigate the peptide bond planarity, including hydrogen atoms, we report a 1.2-Å resolution neutron structure of the oxidized form of high-potential iron-sulfur protein. This high-resolution neutron structure shows that the nucleus positions of the amide protons deviate from the peptide plane and shift toward the acceptors. The planarity of the H─N─C═O plane depends strongly on the pyramidalization of the nitrogen atom. Moreover, the orientation of the amide proton of Cys⁷⁵ is different in the reduced and oxidized states, possibly because of the electron storage capacity of the iron-sulfur cluster.

SUBMITTER: Hanazono Y

PROVIDER: S-EPMC9122329 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Revisiting the concept of peptide bond planarity in an iron-sulfur protein by neutron structure analysis.

Hanazono Yuya Y Hirano Yu Y Takeda Kazuki K Kusaka Katsuhiro K Tamada Taro T Miki Kunio K

Science advances 20220520 20

The planarity of the peptide bond is important for the stability and structure formation of proteins. However, substantial distortion of peptide bonds has been reported in several high-resolution structures and computational analyses. To investigate the peptide bond planarity, including hydrogen atoms, we report a 1.2-Å resolution neutron structure of the oxidized form of high-potential iron-sulfur protein. This high-resolution neutron structure shows that the nucleus positions of the amide prot ...[more]

PMID: 35594350

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