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Author (up) Donoso, R.A.; Perez-Pantoja, D.; Gonzalez, B.
Title Strict and direct transcriptional repression of the pobA gene by benzoate avoids 4-hydroxybenzoate degradation in the pollutant degrader bacterium Cupriavidus necator JMP134 Type
Year 2011 Publication Environmental Microbiology Abbreviated Journal Environ. Microbiol.
Volume 13 Issue 6 Pages 1590-1600
Keywords
Abstract As other environmental bacteria, Cupriavidus necator JMP134 uses benzoate as preferred substrate in mixtures with 4-hydroxybenzoate, strongly inhibiting its degradation. The mechanism underlying this hierarchical use was studied. A C. necator benA mutant, defective in the first step of benzoate degradation, is unable to metabolize 4-hydroxybenzoate when benzoate is also included in the medium, indicating that this substrate and not one of its catabolic intermediates is directly triggering repression. Reverse transcription polymerase chain reaction analysis revealed that 4-hydroxybenzoate 3-hydroxylase-encoding pobA transcripts are nearly absent in presence of benzoate and a fusion of pobA promoter to lacZ reporter confirmed that benzoate drastically decreases the transcription of this gene. Expression of pobA driven by a heterologous promoter in C. necator benA mutant, allows growth on 4-hydroxybenzoate in presence of benzoate, overcoming its repressive effect. In contrast with other bacteria, regulators of benzoate catabolism do not participate in repression of 4-hydroxybenzoate degradation. Moreover, the effect of benzoate on pobA promoter can be observed in heterologous strains with the sole presence of PobR, the transcriptional activator of pobA gene, indicating that PobR is enough to fully reproduce the phenomenon. This novel mechanism for benzoate repression is probably mediated by direct action of benzoate over PobR.
Address [Donoso, Raul A.; Gonzalez, Bernardo] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: bernardo.gonzalez@uai.cl
Corporate Author Thesis
Publisher Wiley-Blackwell Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1462-2912 ISBN Medium
Area Expedition Conference
Notes WOS:000291268900018 Approved
Call Number UAI @ eduardo.moreno @ Serial 147
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Author (up) Donoso, R.A.; Ruiz, D.; Garate-Castro, C.; Villegas, P.; Gonzalez-Pastor, J.E.; de Lorenzo, V.; Gonzalez, B.; Perez-Pantoja, D.
Title Identification of a self-sufficient cytochrome P450 monooxygenase from Cupriavidus pinatubonensis JMP134 involved in 2-hydroxyphenylacetic acid catabolism, via homogentisate pathway Type
Year 2021 Publication Microbial Biotechnology Abbreviated Journal Microb. Biotechnol.
Volume 14 Issue 5 Pages 1944-1960
Keywords COMPLETE GENOME SEQUENCE; ELECTRON-TRANSFER; GENE; DEGRADATION; SYSTEM; STRAIN; P450BM3; GROWTH; DOMAIN; HYDROXYLATION
Abstract The self-sufficient cytochrome P450 RhF and its homologues belonging to the CYP116B subfamily have attracted considerable attention due to the potential for biotechnological applications based in their ability to catalyse an array of challenging oxidative reactions without requiring additional protein partners. In this work, we showed for the first time that a CYP116B self-sufficient cytochrome P450 encoded by the ohpA gene harboured by Cupriavidus pinatubonensis JMP134, a beta-proteobacterium model for biodegradative pathways, catalyses the conversion of 2-hydroxyphenylacetic acid (2-HPA) into homogentisate. Mutational analysis and HPLC metabolite detection in strain JMP134 showed that 2-HPA is degraded through the well-known homogentisate pathway requiring a 2-HPA 5-hydroxylase activity provided by OhpA, which was additionally supported by heterologous expression and enzyme assays. The ohpA gene belongs to an operon including also ohpT, coding for a substrate-binding subunit of a putative transporter, whose expression is driven by an inducible promoter responsive to 2-HPA in presence of a predicted OhpR transcriptional regulator. OhpA homologues can be found in several genera belonging to Actinobacteria and alpha-, beta- and gamma-proteobacteria lineages indicating a widespread distribution of 2-HPA catabolism via homogentisate route. These results provide first time evidence for the natural function of members of the CYP116B self-sufficient oxygenases and represent a significant input to support novel kinetic and structural studies to develop cytochrome P450-based biocatalytic processes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-7915 ISBN Medium
Area Expedition Conference
Notes WOS:000664134700001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1426
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Author (up) Perez-Pantoja, D.; Donoso, R.A.; Sanchez, M.A.; Gonzalez, B.
Title Genuine genetic redundancy in maleylacetate-reductase-encoding genes involved in degradation of haloaromatic compounds by Cupriavidus necator JMP134 Type
Year 2009 Publication Microbiology-Sgm Abbreviated Journal Microbiology-(UK)
Volume 155 Issue Pages 3641-3651
Keywords
Abstract Maleylacetate reductases; (MAR) are required for biodegradation of several substituted aromatic compounds. To date, the functionality of two MAR-encoding genes (tfdF(I) and tfdF(II)) has been reported in Cupriavidus necator JMP134(pJP4), a known degrader of aromatic compounds. These two genes are located in tfd gene clusters involved in the turnover of 2,4-dichlorophenoxyacetate (2,4-D) and 3-chlorobenzoate (3-CB). The C. necator JMP134 genome comprises at least three other genes that putatively encode MAR (tcpD, hqoD and hxqD), but confirmation of their functionality and their role in the catabolism of haloaromatic compounds has not been assessed. RT-PCR expression analyses of C. necator JMP134 cells exposed to 2,4-D, 3-CB, 2,4,6-trichlorophenol (2,4,6-TCP) or 4-fluorobenzoate (4-FB) showed that tfdF(I) and tfdF(II) are induced by haloaromatics channelled to halocatechols as intermediates. In contrast, 2,4,6-TCP only induces tcpD, and any haloaromatic compounds tested did not induce hxqD and hqoD. However, the tcpD, hxqD and hqoD gene products showed MAR activity in cell extracts and provided the MAR function for 2,4-D catabolism when heterologously expressed in MAR-lacking strains. Growth tests for mutants of the five MAR-encoding genes in strain JMP134 showed that none of these genes is essential for degradation of the tested compounds. However, the role of tfdF(I)/tfdF(II) and tcpD genes in the expression of MAR activity during catabolism of 2,4-D and 2,4,6-TCP, respectively, was confirmed by enzyme activity tests in mutants. These results reveal a striking example of genetic redundancy in the degradation of aromatic compounds.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1350-0872 ISBN Medium
Area Expedition Conference
Notes WOS:000272121300019 Approved
Call Number UAI @ eduardo.moreno @ Serial 77
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Author (up) Perez-Pantoja, D.; Leiva-Novoa, P.; Donoso, R.A.; Little, C.; Godoy, M.; Pieper, D.H.; Gonzalez, B.
Title Hierarchy of Carbon Source Utilization in Soil Bacteria: Hegemonic Preference for Benzoate in Complex Aromatic Compound Mixtures Degraded by Cupriavidus pinatubonensis Strain JMP134 Type
Year 2015 Publication Applied And Environmental Microbiology Abbreviated Journal Appl. Environ. Microbiol.
Volume 81 Issue 12 Pages 3914-3924
Keywords
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.
Address [Leiva-Novoa, Pablo; Donoso, Raul A.; Little, Cedric; Gonzalez, Bernardo] Univ Adolfo Ibanez, Ctr Appl Ecol & Sustainabil, Fac Ingn & Ciencias, Santiago, Chile, Email: bernardo.gonzalez@uai.cl
Corporate Author Thesis
Publisher Amer Soc Microbiology Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0099-2240 ISBN Medium
Area Expedition Conference
Notes WOS:000354864000002 Approved
Call Number UAI @ eduardo.moreno @ Serial 491
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Author (up) Zuniga, A.; Donoso, R.A.; Ruiz, D.; Ruz, G.A.; Gonzalez, B.
Title Quorum-Sensing Systems in the Plant Growth-Promoting Bacterium Paraburkholderia phytofirmans PsJN Exhibit Cross-Regulation and Are Involved in Biofilm Formation Type
Year 2017 Publication Molecular Plant-Microbe Interactions Abbreviated Journal Mol. Plant-Microbe Interact.
Volume 30 Issue 7 Pages 557-565
Keywords
Abstract Quorum-sensing systems play important roles in host colonization and host establishment of Burkholderiales species. Beneficial Paraburkholderia species share a conserved quorum-sensing (QS) system, designated BraI/R, that controls different phenotypes. In this context, the plant growth-promoting bacterium Paraburkholderia phytofirmans PsJN possesses two different homoserine lactone QS systems BpI. 1/R.1 and BpI. 2/R.2 (BraI/R-like QS system). The BpI. 1/R.1 QS system was previously reported to be important to colonize and produce beneficial effects in Arabidopsis thaliana plants. Here, we analyzed the temporal variations of the QS gene transcript levels in the wild-type strain colonizing plant roots. The gene expression patterns showed relevant differences in both QS systems compared with the wild-type strain in the unplanted control treatment. The gene expression data were used to reconstruct a regulatory network model of QS systems in P.phytofirmans PsJN, using a Boolean network model. Also, we examined the phenotypic traits and transcript levels of genes involved in QS systems, using P. phytofirmans mutants in homoserine lactone synthases genes. We observed that the BpI. 1/R.1 QS system regulates biofilm formation production in strain PsJN and this phenotype was associated with the lower expression of a specific extracytoplasmic function sigma factor ecf26.1 gene (implicated in biofilm formation) in the bpI.1 mutant strain.
Address [Gonzalez, Bernardo] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Millennium Nucleus Ctr Plant Syst & Synthet Biol, Santiago, Chile, Email: bernardo.gonzalez@uai.cl
Corporate Author Thesis
Publisher Amer Phytopathological Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0894-0282 ISBN Medium
Area Expedition Conference
Notes WOS:000404048400004 Approved
Call Number UAI @ eduardo.moreno @ Serial 739
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