title: The genome of Variovorax paradoxus strain TBEA6 provides new understandings for the catabolism of 3,3'-thiodipropionic acid and hence the production of polythioesters.
abstract: The betaproteobacterium Variovorax paradoxus strain TBEA6 is capable of using 3,3'-thiodipropionic acid (TDP) as sole carbon and energy source for growth. This thioether is employed for several industrial applications. It can be applied as precursor for the biotechnical production of polythioesters (PTE), which represent persistent bioplastics. Consequently, the genome of V. paradoxus strain TBEA6 was sequenced. The draft genome sequence comprises approximately 7.2Mbp and 6852 predicted open reading frames. Furthermore, transposon mutagenesis to unravel the catabolism of TDP in strain TBEA6 was performed. Screening of 20,000 mutants mapped the insertions of Tn5::mob in 32 mutants, which all showed no growth with TDP as sole carbon source. Based on the annotated genome sequence together with transposon-induced mutagenesis, defined gene deletions, in silico analyses and comparative genomics, a comprehensive pathway for the catabolism of TDP is proposed: TDP is imported via the tripartite tricarboxcylate transport system and/or the TRAP-type dicarboxylate transport system. The initial cleavage of TDP into 3-hydroxypropionic acid (3HP) and 3-mercaptopropionic acid (3MP), which serves as precursor substrate for PTE synthesis, is most probably performed by the FAD-dependent oxidoreductase Fox. 3HP is presumably catabolized via malonate semialdehyde, whereas 3MP is oxygenated by the 3MP-dioxygenase Mdo yielding 3-sulfinopropionic acid (3SP). Afterwards, 3SP is linked to coenzyme A. The next step is the abstraction of sulfite by a desulfinase, and the resulting propionyl-CoA enters the central metabolism. Sulfite is oxidized to sulfate by the sulfite-oxidizing enzyme SoeABC and is subsequently excreted by the cells by the sulfate exporter Pse.
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
authors.forename: Jan Hendrik
authors.initials: JH
authors.lastname: Wübbeler
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Hiessl
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Meinert
authors.affiliation: Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, Göttingen, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Poehlein
authors.affiliation: Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, Göttingen, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Schuldes
authors.affiliation: Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, Göttingen, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Daniel
authors.affiliation: Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany; Faculty of Biology, King Abdulaziz University, Jeddah, Saudi Arabia. Electronic address: steinbu@uni-muenster.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Steinbüchel
mesh_terms: D020562:Betaproteobacteria / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D016680:Genome, Bacterial; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames; D011422:Propionates / Q000378:metabolism*; D017422:Sequence Analysis, DNA / Q000379:methods*; D013440:Sulfides / Q000378:metabolism
chemical_list: D011422:Propionates; D013440:Sulfides; C013298:thiodipropionic acid
keywords: 3,3′-Thiodipropionate catabolism; Genome sequence; Polythioester; Tn5::mob mutagenesis; Variovorax paradoxus