Coniferyl Alcohol Radical Detection by the Dirigent Protein At DIR6 Monitored by EPR

Camille Modolo (1) , Lu Ren (1) , Eric Besson (2) , Viviane Robert (1) , Stéphane Gastaldi (2) , Pierre Rousselot- Pailley (1) , Thierry Tron (1)

1 ISM2 - Institut des Sciences Moléculaires de Marseille
2 ICR - Institut de Chimie Radicalaire

Plant dirigent proteins (DIRs) control the stereoselectivity of the monolignol coniferyl alcohol radical coupling. The main mechanistic hypothesis on this chemo-and stereoselective reaction invokes a binding of coniferyl alcohol radical substrates in the dirigent protein active site so that only one enantiomeric form can be produced. We have studied the influence of the Arabidopsis thaliana AtDIR6 protein on the transient coniferyl alcohol radical by EPR. Herein, we show that AtDIR6 stabilizes coniferyl alcohol radicals prior to directing their coupling towards the formation of (-)-pinoresinol.

Domaines: Biochimie [q-bio.BM]; Botanique

Camille Modolo, Lu Ren, Eric Besson, Viviane Robert, Stéphane Gastaldi, et al.. Coniferyl Alcohol Radical Detection by the Dirigent Protein At DIR6 Monitored by EPR. ChemBioChem, 2021, 22 (6), pp.992-995. ⟨10.1002/cbic.202000650⟩. ⟨hal-03121563⟩