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An Artificial Heme Enzyme for Cyclopropanation Reactions.

ABSTRACT: An artificial heme enzyme was created through self-assembly from hemin and the lactococcal multidrug resistance regulator (LmrR). The crystal structure shows the heme bound inside the hydrophobic pore of the protein, where it appears inaccessible for substrates. However, good catalytic activity and moderate enantioselectivity was observed in an abiological cyclopropanation reaction. We propose that the dynamic nature of the structure of the LmrR protein is key to the observed activity. This was supported by molecular dynamics simulations, which showed transient formation of opened conformations that allow the binding of substrates and the formation of pre-catalytic structures.

SUBMITTER: Villarino L

PROVIDER: S-EPMC6033091 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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An Artificial Heme Enzyme for Cyclopropanation Reactions.

Villarino Lara L Splan Kathryn E KE Reddem Eswar E Alonso-Cotchico Lur L Gutiérrez de Souza Cora C Lledós Agustí A Maréchal Jean-Didier JD Thunnissen Andy-Mark W H AWH Roelfes Gerard G

Angewandte Chemie (International ed. in English) 20180529 26

An artificial heme enzyme was created through self-assembly from hemin and the lactococcal multidrug resistance regulator (LmrR). The crystal structure shows the heme bound inside the hydrophobic pore of the protein, where it appears inaccessible for substrates. However, good catalytic activity and moderate enantioselectivity was observed in an abiological cyclopropanation reaction. We propose that the dynamic nature of the structure of the LmrR protein is key to the observed activity. This was ...[more]

PMID: 29719099

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