title: X-ray structures of Nfs2, the plastidial cysteine desulfurase from Arabidopsis thaliana.
abstract: The chloroplastic Arabidopsis thaliana Nfs2 (AtNfs2) is a group II pyridoxal 5'-phosphate-dependent cysteine desulfurase that is involved in the initial steps of iron-sulfur cluster biogenesis. The group II cysteine desulfurases require the presence of sulfurtransferases such as SufE proteins for optimal activity. Compared with group I cysteine desulfurases, proteins of this group contains a smaller extended lobe harbouring the catalytic cysteine and have a β-hairpin constraining the active site. Here, two crystal structures of AtNfs2 are reported: a wild-type form with the catalytic cysteine in a persulfide-intermediate state and a C384S variant mimicking the resting state of the enzyme. In both structures the well conserved Lys241 covalently binds pyridoxal 5'-phosphate, forming an internal aldimine. Based on available homologous bacterial complexes, a model of a complex between AtNfs2 and the SufE domain of its biological partner AtSufE1 is proposed, revealing the nature of the binding sites.
authors.affiliation: Université de Lorraine, UMR 7036 CRM2, BioMod Group, BP 70239, 54506 Vandoeuvre-lès-Nancy, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Roret
authors.affiliation: Université de Lorraine, UMR 1136 Interactions Arbres Microorganismes, 54500 Vandoeuvre-lès-Nancy, France.
authors.forename: Henri
authors.initials: H
authors.lastname: Pégeot
authors.affiliation: Université de Lorraine, UMR 1136 Interactions Arbres Microorganismes, 54500 Vandoeuvre-lès-Nancy, France.
authors.forename: Jérémy
authors.initials: J
authors.lastname: Couturier
authors.affiliation: Université de Lorraine, UMR 7036 CRM2, BioMod Group, BP 70239, 54506 Vandoeuvre-lès-Nancy, France.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Mulliert
authors.affiliation: Université de Lorraine, UMR 1136 Interactions Arbres Microorganismes, 54500 Vandoeuvre-lès-Nancy, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rouhier
authors.affiliation: Université de Lorraine, UMR 7036 CRM2, BioMod Group, BP 70239, 54506 Vandoeuvre-lès-Nancy, France.
authors.forename: Claude
authors.initials: C
authors.lastname: Didierjean
mesh_terms: D029681:Arabidopsis Proteins / Q000737:chemistry*; D001483:Base Sequence; D013437:Carbon-Sulfur Lyases / Q000737:chemistry*; D018360:Crystallography, X-Ray; D017931:DNA Primers; D008958:Models, Molecular; D018087:Plastids / Q000201:enzymology*; D011487:Protein Conformation
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; D013437:Carbon-Sulfur Lyases; C080546:cysteine desulfurase
keywords: Arabidopsis thaliana; SUF machinery; cysteine desulfurase; iron–sulfur cluster