title: Identification of the phd gene cluster responsible for phenylpropanoid utilization in Corynebacterium glutamicum.
abstract: Phenylpropanoids as abundant, lignin-derived compounds represent sustainable feedstocks for biotechnological production processes. We found that the biotechnologically important soil bacterium Corynebacterium glutamicum is able to grow on phenylpropanoids such as p-coumaric acid, ferulic acid, caffeic acid, and 3-(4-hydroxyphenyl)propionic acid as sole carbon and energy sources. Global gene expression analyses identified a gene cluster (cg0340-cg0341 and cg0344-cg0347), which showed increased transcription levels in response to phenylpropanoids. The gene cg0340 (designated phdT) encodes for a putative transporter protein, whereas cg0341 and cg0344-cg0347 (phdA-E) encode enzymes involved in the β-oxidation of phenylpropanoids. The phd gene cluster is transcriptionally controlled by a MarR-type repressor encoded by cg0343 (phdR). Cultivation experiments conducted with C. glutamicum strains carrying single-gene deletions showed that loss of phdA, phdB, phdC, or phdE abolished growth of C. glutamicum with all phenylpropanoid substrates tested. The deletion of phdD (encoding for putative acyl-CoA dehydrogenase) additionally abolished growth with the α,β-saturated phenylpropanoid 3-(4-hydroxyphenyl)propionic acid. However, the observed growth defect of all constructed single-gene deletion strains could be abolished through plasmid-borne expression of the respective genes. These results and the intracellular accumulation of pathway intermediates determined via LC-ESI-MS/MS in single-gene deletion mutants showed that the phd gene cluster encodes for a CoA-dependent, β-oxidative deacetylation pathway, which is essential for the utilization of phenylpropanoids in C. glutamicum.
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Nicolai
authors.initials: N
authors.lastname: Kallscheuer
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Vogt
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Jannick
authors.initials: J
authors.lastname: Kappelmann
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Krumbach
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Noack
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bott
authors.affiliation: Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425, Jülich, Germany. j.marienhagen@fz-juelich.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Marienhagen
mesh_terms: D001555:Benzene Derivatives / Q000378:metabolism*; D002244:Carbon / Q000378:metabolism; D002934:Cinnamates / Q000378:metabolism*; D048230:Corynebacterium glutamicum / Q000235:genetics* / Q000378:metabolism*; D004734:Energy Metabolism; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D005810:Multigene Family
chemical_list: D001555:Benzene Derivatives; D002934:Cinnamates; D002244:Carbon
keywords: Aromatics; Corynebacterium glutamicum; Degradation pathways; Lignin; Phenylpropanoids; β-oxidation