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Cradle-loop barrels and the concept of metafolds in protein classification by natural descent

Department of Protein Evolution, Max-Planck-Institute for Developmental Biology, Spemannstr. 35, D-72076 Tübingen, Germany.
Current Opinion in Structural Biology (Impact Factor: 8.75). 07/2008; 18(3):358-65. DOI: 10.1016/j.sbi.2008.02.006
Source: PubMed

ABSTRACT Current classification systems for protein structure show many inconsistencies both within and between systems. The metafold concept was introduced to identify fold similarities by consensus and thus provide a more unified view of fold space. Using cradle-loop barrels as an example, we propose to use the metafold as the next hierarchical level above the fold, encompassing a group of topologically related folds for which a homologous relationship has been substantiated. We see this as an important step on the way to a classification of proteins by natural descent.

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