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Evolutionary relationships between heme-binding ferredoxin ? + ? barrels.

ABSTRACT: The ? + ? barrel superfamily of the ferredoxin-like fold consists of a functionally diverse group of evolutionarily related proteins. The barrel architecture of these proteins is formed by either homo-/hetero-dimerization or duplication and fusion of ferredoxin-like domains. Several members of this superfamily bind heme in order to carry out their functions.We analyze the heme-binding sites in these proteins as well as their barrel topologies. Our comparative structural analysis of these heme-binding barrels reveals two distinct modes of packing of the ferredoxin-like domains to constitute the ? + ? barrel, which is typified by the Type-1/IsdG-like and Type-2/OxdA-like proteins, respectively. We examine the heme-binding pockets and explore the versatility of the ? + ? barrels ability to accommodate heme or heme-related moieties, such as siroheme, in at least three different sites, namely, the mode seen in IsdG/OxdA, Cld/DyP/EfeB/HemQ and siroheme decarboxylase barrels.Our study offers insights into the plausible evolutionary relationships between the two distinct barrel packing topologies and relate the observed heme-binding sites to these topologies.

SUBMITTER: Acharya G

PROVIDER: S-EPMC4835899 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Evolutionary relationships between heme-binding ferredoxin α + β barrels.

Acharya Giriraj G Kaur Gurmeet G Subramanian Srikrishna S

BMC bioinformatics 20160418

<h4>Background</h4>The α + β barrel superfamily of the ferredoxin-like fold consists of a functionally diverse group of evolutionarily related proteins. The barrel architecture of these proteins is formed by either homo-/hetero-dimerization or duplication and fusion of ferredoxin-like domains. Several members of this superfamily bind heme in order to carry out their functions.<h4>Results</h4>We analyze the heme-binding sites in these proteins as well as their barrel topologies. Our comparative s ...[more]

PMID: 27089923

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Dataset Information

Evolutionary relationships between heme-binding ferredoxin ? + ? barrels.

Publications

Evolutionary relationships between heme-binding ferredoxin α + β barrels.

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