View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Chemistry & Biology Article Ralfuranone Biosynthesis in Ralstonia solanacearum Suggests Functional Divergence in the Quinone Synthetase Family of Enzymes Barbara Wackler,1 Patrick Schneider,1 Jonathan M. Jacobs,2 Julia Pauly,1 Caitilyn Allen,2 Markus Nett,3 and Dirk Hoffmeister1,* 1Department Pharmaceutical Biology at the Hans-Kno¨ ll-Institute, Friedrich-Schiller-Universita¨ t Jena, Beutenbergstrasse 11a, 07745 Jena, Germany 2Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, USA 3Leibniz Institute for Natural Product Research and Infection Biology—Hans-Kno¨ ll-Institute, Beutenbergstrasse 11a, 07745 Jena, Germany *Correspondence:
[email protected] DOI 10.1016/j.chembiol.2011.01.010 SUMMARY VsrAD and PhcA, and secondary metabolism has been demon- strated and led to the identification of a new small molecule, Ralstonia solanacearum is a destructive crop plant ralfuranone (4-phenylfuran-2(5H)-one, 1, Figure 1)(Schneider pathogen and produces ralfuranone, i.e., a mono- et al., 2009). Although achiral and little functionalized, this bicy- phenyl-substituted furanone. Extensive feeding clic secondary product attracted our attention as the origin of experiments with 13C-labeled L-phenylalanine now the carbon atoms was elusive. Initially, we hypothesized that proved that all carbon atoms of the heterocycle the aromatic system may be derived from L-phenylalanine, and derive, after deamination, from this aromatic amino that transfer of malonyl-CoA to the former may provide the carbon atoms to complete furanone synthesis. Chemical char- acid. A genetic locus was identified which encodes acterization of a new, yet related natural product, ralfuranone B the aminotransferase RalD and the furanone synthe- (2, Figure 1), prompted us to propose a revised biosynthetic tase RalA.