title: Hierarchy of Carbon Source Utilization in Soil Bacteria: Hegemonic Preference for Benzoate in Complex Aromatic Compound Mixtures Degraded by Cupriavidus pinatubonensis Strain JMP134.
abstract: Cupriavidus pinatubonensis JMP134, like many other environmental bacteria, uses a range of aromatic compounds as carbon sources. Previous reports have shown a preference for benzoate when this bacterium grows on binary mixtures composed of this aromatic compound and 4-hydroxybenzoate or phenol. However, this observation has not been extended to other aromatic mixtures resembling a more archetypal context. We carried out a systematic study on the substrate preference of C. pinatubonensis JMP134 growing on representative aromatic compounds channeled through different catabolic pathways described in aerobic bacteria. Growth tests of nearly the entire set of binary combinations and in mixtures composed of 5 or 6 aromatic components showed that benzoate and phenol were always the preferred and deferred growth substrates, respectively. This pattern was supported by kinetic analyses that showed shorter times to initiate consumption of benzoate in aromatic compound mixtures. Gene expression analysis by real-time reverse transcription-PCR (RT-PCR) showed that, in all mixtures, the repression by benzoate over other catabolic pathways was exerted mainly at the transcriptional level. Additionally, inhibition of benzoate catabolism suggests that its multiple repressive actions are not mediated by a sole mechanism, as suggested by dissimilar requirements of benzoate degradation for effective repression in different aromatic compound mixtures. The hegemonic preference for benzoate over multiple aromatic carbon sources is not explained on the basis of growth rate and/or biomass yield on each single substrate or by obvious chemical or metabolic properties of these aromatic compounds.
authors: Millennium Nucleus on Plant Functional Genomics, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors: Danilo
authors: D
authors: Pérez-Pantoja
authors: Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Center of Applied Ecology and Sustainability, Santiago, Chile Millennium Nucleus on Plant Functional Genomics, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors: Pablo
authors: P
authors: Leiva-Novoa
authors: Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Center of Applied Ecology and Sustainability, Santiago, Chile Millennium Nucleus on Plant Functional Genomics, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors: Raúl A
authors: RA
authors: Donoso
authors: Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Center of Applied Ecology and Sustainability, Santiago, Chile.
authors: Cedric
authors: C
authors: Little
authors: Millennium Nucleus on Plant Functional Genomics, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors: Margarita
authors: M
authors: Godoy
authors: Microbial Interactions Processes Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Dietmar H
authors: DH
authors: Pieper
authors: Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Center of Applied Ecology and Sustainability, Santiago, Chile Millennium Nucleus on Plant Functional Genomics, Pontificia Universidad Católica de Chile, Santiago, Chile bernardo.gonzalez@uai.cl.
authors: Bernardo
authors: B
authors: González
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001565:Benzoates / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D049921:Cupriavidus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006841:Hydrocarbons, Aromatic / Q000378:metabolism*; D009154:Mutation; D010226:Parabens / Q000378:metabolism; D019800:Phenol / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012988:Soil Microbiology; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D001565:Benzoates; D003470:Culture Media; D006841:Hydrocarbons, Aromatic; D010226:Parabens; D019800:Phenol; D002244:Carbon; C038193:4-hydroxybenzoic acid