title: 3-Sulfinopropionyl-coenzyme A (3SP-CoA) desulfinase from Advenella mimigardefordensis DPN7(T): crystal structure and function of a desulfinase with an acyl-CoA dehydrogenase fold.
abstract: 3-Sulfinopropionyl-coenzyme A (3SP-CoA) desulfinase (AcdDPN7; EC 3.13.1.4) was identified during investigation of the 3,3'-dithiodipropionic acid (DTDP) catabolic pathway in the betaproteobacterium Advenella mimigardefordensis strain DPN7(T). DTDP is an organic disulfide and a precursor for the synthesis of polythioesters (PTEs) in bacteria, and is of interest for biotechnological PTE production. AcdDPN7 catalyzes sulfur abstraction from 3SP-CoA, a key step during the catabolism of DTDP. Here, the crystal structures of apo AcdDPN7 at 1.89 Å resolution and of its complex with the CoA moiety from the substrate analogue succinyl-CoA at 2.30 Å resolution are presented. The apo structure shows that AcdDPN7 belongs to the acyl-CoA dehydrogenase superfamily fold and that it is a tetramer, with each subunit containing one flavin adenine dinucleotide (FAD) molecule. The enzyme does not show any dehydrogenase activity. Dehydrogenase activity would require a catalytic base (Glu or Asp residue) at either position 246 or position 366, where a glutamine and a glycine are instead found, respectively, in this desulfinase. The positioning of CoA in the crystal complex enabled the modelling of a substrate complex containing 3SP-CoA. This indicates that Arg84 is a key residue in the desulfination reaction. An Arg84Lys mutant showed a complete loss of enzymatic activity, suggesting that the guanidinium group of the arginine is essential for desulfination. AcdDPN7 is the first desulfinase with an acyl-CoA dehydrogenase fold to be reported, which underlines the versatility of this enzyme scaffold.
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Schürmann
authors.affiliation: European Molecular Biology Laboratory Hamburg Unit, EMBL, Notkestrasse 85, 22603 Hamburg, Germany.
authors.forename: Rob
authors.initials: R
authors.lastname: Meijers
authors.affiliation: European Molecular Biology Laboratory Hamburg Unit, EMBL, Notkestrasse 85, 22603 Hamburg, Germany.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Schneider
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Steinbüchel
authors.affiliation: European Molecular Biology Laboratory Hamburg Unit, EMBL, Notkestrasse 85, 22603 Hamburg, Germany.
authors.forename: Michele
authors.initials: M
authors.lastname: Cianci
mesh_terms: D042964:Acyl-CoA Dehydrogenase / Q000737:chemistry*; D042401:Alcaligenaceae / Q000201:enzymology*; D003065:Coenzyme A / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004798:Enzymes / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011422:Propionates / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding
chemical_list: D004798:Enzymes; D011422:Propionates; C009351:3-sulfinopropionic acid; D042964:Acyl-CoA Dehydrogenase; D003065:Coenzyme A
keywords: 3,3′-dithiodipropionic acid; 3-sulfinopropionyl-coenzyme A; arginine; dehydrogenase fold; desulfinase