Publications (37)163.5 Total impact
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Article: Identification of a missing link in the evolution of an enzyme into a transcriptional regulator.
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ABSTRACT: The evolution of transcriptional regulators through the recruitment of DNA-binding domains by enzymes is a widely held notion. However, few experimental approaches have directly addressed this hypothesis. Here we report the reconstruction of a plausible pathway for the evolution of an enzyme into a transcriptional regulator. The BzdR protein is the prototype of a subfamily of prokaryotic transcriptional regulators that controls the expression of genes involved in the anaerobic degradation of benzoate. We have shown that BzdR consists of an N-terminal DNA-binding domain connected through a linker to a C-terminal effector-binding domain that shows significant identity to the shikimate kinase (SK). The construction of active synthetic BzdR-like regulators by fusing the DNA-binding domain of BzdR to the Escherichia coli SKI protein strongly supports the notion that an ancestral SK domain could have been involved in the evolutionary origin of BzdR. The loss of the enzymatic activity of the ancestral SK domain was essential for it to evolve as a regulatory domain in the current BzdR protein. This work also supports the view that enzymes precede the emergence of the regulatory systems that may control their expression.PLoS ONE 01/2013; 8(3):e57518. · 4.09 Impact Factor -
Article: Aerobic degradation of aromatic compounds.
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ABSTRACT: Our view on the bacterial responses to the aerobic degradation of aromatic compounds has been enriched considerably by the current omic methodologies and systems biology approaches, revealing the participation of intricate metabolic and regulatory networks. New enzymes, transporters, and specific/global regulatory systems have been recently characterized, and reveal that the widespread biodegradation capabilities extend to unexpected substrates such as lignin. A completely different biochemical strategy based on the formation of aryl-CoA epoxide intermediates has been unraveled for aerobic hybrid pathways, such as those involved in benzoate and phenylacetate degradation. Aromatic degradation pathways are also an important source of metabolic exchange factors and, therefore, they play a previously unrecognized biological role in cell-to-cell communication. Beyond the native bacterial biodegradation capabilities, pathway evolution as well as computational and synthetic biology approaches are emerging as powerful tools to design novel strain-specific pathways for degradation of xenobiotic compounds.Current opinion in biotechnology 11/2012; · 7.82 Impact Factor -
Article: Characterization of the mbd cluster encoding the anaerobic 3-methylbenzoyl-CoA central pathway.
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ABSTRACT: The mbd cluster encoding genes of the 3-methylbenzoyl-CoA pathway involved in the anaerobic catabolism of 3-methylbenzoate and m-xylene was characterized for the first time in the denitrifying β-Proteobacterium Azoarcus sp. CIB. The mbdA gene product was identified as a 3-methylbenzoate-CoA ligase required for 3-methylbenzoate activation; its substrate spectrum was unique in activating all three methylbenzoate isomers. An inducible 3-methylbenzoyl-CoA reductase (mbdONQP gene products), displaying significant amino acid sequence similarities to known class I benzoyl-CoA reductases catalysed the ATP-dependent reduction of 3-methylbenzoyl-CoA to a methyldienoyl-CoA. The mbdW gene encodes a methyldienoyl-CoA hydratase that hydrated the methyldienoyl-CoA to a methyl-6-hydroxymonoenoyl-CoA compound. The mbd cluster also contains the genes predicted to be involved in the subsequent steps of the 3-methylbenzoyl-CoA pathway as well as the electron donor system for the reductase activity. Whereas the catabolic mbd genes are organized in two divergent inducible operons, the putative mbdR regulatory gene was transcribed separately and showed constitutive expression. The efficient expression of the mbd genes required the oxygen-dependent AcpR activator, and it was subject of carbon catabolite repression by some organic acids and amino acids. Sequence analyses suggest that the mbd gene cluster was recruited by Azoarcus sp. CIB through horizontal gene transfer.Environmental Microbiology 06/2012; · 5.84 Impact Factor -
Article: A finely tuned regulatory circuit of the nicotinic acid degradation pathway in Pseudomonas putida.
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ABSTRACT: The biochemistry of nicotinic acid (NA) degradation is known but the transcriptional control of the genes involved is still poorly studied. We report here the transcriptional regulatory circuit of the nic genes responsible for the aerobic degradation of NA in Pseudomonas putida KT2440. The three NA-inducible catabolic operons, i.e. nicAB, encoding the upper pathway that converts NA into 6-hydroxynicotinic acid (6HNA), and the nicCDEFTP and nicXR operons, responsible for channelling 6HNA to the central metabolism, are driven by the Pa, Pc and Px promoters respectively. The nicR regulatory gene encodes a MarR-like protein that represses the activity of the divergent Pc and Px promoters being 6HNA the inducer molecule. A new gene, nicS, that is associated to the nicAB genes in the genomes of different γ- and β-Proteobacteria, encodes a TetR-like regulator that represses the activity of Pa in the absence of the NA/6HNA inducers. The NA regulatory circuit in P. putida has evolved an additional repression loop based on the NicR-dependent cross regulation of the nicS gene, thus assuring a tight transcriptional control of the catabolic genes that may prevent depletion of this vitamin B3 when needed for the synthesis of essential cofactors.Environmental Microbiology 03/2011; 13(7):1718-32. · 5.84 Impact Factor -
Article: Unravelling the gallic acid degradation pathway in bacteria: the gal cluster from Pseudomonas putida.
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ABSTRACT: Gallic acid (3,4,5-trihydroxybenzoic acid, GA) is widely distributed in nature, being a major phenolic pollutant and a commonly used antioxidant and building-block for drug development. We have characterized the first complete cluster (gal genes) responsible for growth in GA in a derivative of the model bacterium Pseudomonas putida KT2440. GalT mediates specific GA uptake and chemotaxis, and highlights the critical role of GA transport in bacterial adaptation to GA consumption. The proposed GA degradation via the central intermediate 4-oxalomesaconic acid (OMA) was revisited and all enzymes involved have been identified. Thus, GalD is the prototype of a new subfamily of isomerases that catalyses a biochemical step that remained unknown, i.e. the tautomerization of the OMAketo generated by the GalA dioxygenase to OMAenol. GalB is the founding member of a new family of zinc-containing hydratases that converts OMAenol into 4-carboxy-4-hydroxy-2-oxoadipic acid (CHA). galC encodes the aldolase catalysing CHA cleavage to pyruvic and oxaloacetic acids. The presence of homologous gal clusters outside the Pseudomonas genus sheds light on the evolution and ecology of the gal genes in GA degraders. The gal genes were used for expanding the metabolic abilities of heterologous hosts towards GA degradation, and for engineering a GA cellular biosensor.Molecular Microbiology 01/2011; 79(2):359-74. · 5.01 Impact Factor -
Article: Biochemical characterization of the transcriptional regulator BzdR from Azoarcus sp. CIB.
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ABSTRACT: The BzdR transcriptional regulator that controls the P(N) promoter responsible for the anaerobic catabolism of benzoate in Azoarcus sp. CIB constitutes the prototype of a new subfamily of transcriptional regulators. Here, we provide some insights about the functional-structural relationships of the BzdR protein. Analytical ultracentrifugation studies revealed that BzdR is homodimeric in solution. An electron microscopy three-dimensional reconstruction of the BzdR dimer has been obtained, and the predicted structures of the respective N- and C-terminal domains of each BzdR monomer could be fitted into such a reconstruction. Gel retardation and ultracentrifugation experiments have shown that the binding of BzdR to its cognate promoter is cooperative. Different biochemical approaches revealed that the effector molecule benzoyl-CoA induces conformational changes in BzdR without affecting its oligomeric state. The BzdR-dependent inhibition of the P(N) promoter and its activation in the presence of benzoyl-CoA have been established by in vitro transcription assays. The monomeric BzdR4 and BzdR5 mutant regulators revealed that dimerization of BzdR is essential for DNA binding. Remarkably, a BzdRΔL protein lacking the linker region connecting the N- and C-terminal domains of BzdR is also dimeric and behaves as a super-repressor of the P(N) promoter. These data suggest that the linker region of BzdR is not essential for protein dimerization, but rather it is required to transfer the conformational changes induced by the benzoyl-CoA to the DNA binding domain leading to the release of the repressor. A model of action of the BzdR regulator has been proposed.Journal of Biological Chemistry 11/2010; 285(46):35694-705. · 4.77 Impact Factor -
Article: A preliminary crystallographic study of recombinant NicX, an Fe(2+)-dependent 2,5-dihydroxypyridine dioxygenase from Pseudomonas putida KT2440.
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ABSTRACT: NicX from Pseudomonas putida KT2440 is an Fe(2+)-dependent dioxygenase that is involved in the aerobic degradation of nicotinic acid. The enzyme converts 2,5-dihydroxypyridine to N-formylmaleamic acid when overexpressed in Escherichia coli. Biophysical characterization of NicX by analytical gel-filtration chromatography revealed that it behaves as an oligomeric assembly in solution, with an apparent molecular weight that is consistent with a hexameric species. NicX was crystallized by the hanging-drop vapour-diffusion method at 291 K. Diffraction data were collected to a resolution of 2.0 A at the ESRF. The crystals most probably belong to the orthorhombic space group C222 or C222(1). The estimated Matthews coefficient was 2.4 A(3) Da(-1), corresponding to 50% solvent content, which is consistent with the presence of three protein molecules in the asymmetric unit. Analysis of the crystal data together with chromatographic results supports NicX being a hexameric assembly composed of two cyclic trimers. Currently, crystallization of recombinant selenomethionine-containing NicX is in progress.Acta Crystallographica Section F Structural Biology and Crystallization Communications 05/2010; 66(Pt 5):549-53. · 0.51 Impact Factor -
Article: Identification of the Geobacter metallireducens bamVW two-component system, involved in transcriptional regulation of aromatic degradation.
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ABSTRACT: Regulation of aromatic degradation in obligate anaerobes was studied in the Fe(III)-respiring model organism Geobacter metallireducens GS-15. A two-component system and a sigma54-dependent promoter were identified that are both involved in the regulation of the gene coding for benzoate-coenzyme A ligase, catalyzing the initial step of benzoate degradation.Applied and environmental microbiology 11/2009; 76(1):383-5. · 3.69 Impact Factor -
Article: 3-Hydroxyphenylpropionate and Phenylpropionate Are Synergistic Activators of the MhpR Transcriptional Regulator from Escherichia coli
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ABSTRACT: The degradation of the aromatic compound phenylpropionate (PP) in Escherichia coli K-12 requires the activation of two different catabolic pathways coded by the hca and the mhp gene clusters involved in the mineralization of PP and 3-hydroxyphenylpropionate (3HPP), respectively. The compound 3-(2,3-dihydroxyphenyl)propionate (DHPP) is a common intermediate of both pathways which must be cleaved by the MhpB dioxygenase before entering into the primary cell metabolism. Therefore, the degradation of PP has to be controlled by both its specific regulator (HcaR) but also by the MhpR regulator of the mhp cluster. We have demonstrated that 3HPP and DHPP are the true and best activators of MhpR, whereas PP only induces no response. However, in vivo and in vitro transcription experiments have demonstrated that PP activates the MhpR regulator synergistically with the true inducers, representing the first case of such a peculiar synergistic effect described for a bacterial regulator. The three compounds enhanced the interaction of MhpR with its DNA operator in electrophoretic mobility shift assays. Inducer binding to MhpR is detected by circular dichroism and fluorescence spectroscopies. Fluorescence quenching measurements have revealed that the true inducers (3HPP and DHPP) and PP bind with similar affinities and independently to MhpR. This type of dual-metabolite synergy provides great potential for a rapid modulation of gene expression and represents an important feature of transcriptional control. The mhp regulatory system is an example of the high complexity achievable in prokaryotes.Journal of Biological Chemistry 08/2009; 284(32):21218-21228. · 4.77 Impact Factor -
Article: Anaerobic catabolism of aromatic compounds: a genetic and genomic view.
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ABSTRACT: Aromatic compounds belong to one of the most widely distributed classes of organic compounds in nature, and a significant number of xenobiotics belong to this family of compounds. Since many habitats containing large amounts of aromatic compounds are often anoxic, the anaerobic catabolism of aromatic compounds by microorganisms becomes crucial in biogeochemical cycles and in the sustainable development of the biosphere. The mineralization of aromatic compounds by facultative or obligate anaerobic bacteria can be coupled to anaerobic respiration with a variety of electron acceptors as well as to fermentation and anoxygenic photosynthesis. Since the redox potential of the electron-accepting system dictates the degradative strategy, there is wide biochemical diversity among anaerobic aromatic degraders. However, the genetic determinants of all these processes and the mechanisms involved in their regulation are much less studied. This review focuses on the recent findings that standard molecular biology approaches together with new high-throughput technologies (e.g., genome sequencing, transcriptomics, proteomics, and metagenomics) have provided regarding the genetics, regulation, ecophysiology, and evolution of anaerobic aromatic degradation pathways. These studies revealed that the anaerobic catabolism of aromatic compounds is more diverse and widespread than previously thought, and the complex metabolic and stress programs associated with the use of aromatic compounds under anaerobic conditions are starting to be unraveled. Anaerobic biotransformation processes based on unprecedented enzymes and pathways with novel metabolic capabilities, as well as the design of novel regulatory circuits and catabolic networks of great biotechnological potential in synthetic biology, are now feasible to approach.Microbiology and molecular biology reviews: MMBR 04/2009; 73(1):71-133. · 12.59 Impact Factor -
Article: Analysis of dibenzothiophene desulfurization in a recombinant Pseudomonas putida strain.
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ABSTRACT: Biodesulfurization was monitored in a recombinant Pseudomonas putida CECT5279 strain. DszB desulfinase activity reached a sharp maximum at the early exponential phase, but it rapidly decreased at later growth phases. A model two-step resting-cell process combining sequentially P. putida cells from the late and early exponential growth phases was designed to significantly increase biodesulfurization.Applied and environmental microbiology 01/2009; 75(3):875-7. · 3.69 Impact Factor -
Article: Deciphering the genetic determinants for aerobic nicotinic acid degradation: the nic cluster from Pseudomonas putida KT2440.
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ABSTRACT: The aerobic catabolism of nicotinic acid (NA) is considered a model system for degradation of N-heterocyclic aromatic compounds, some of which are major environmental pollutants; however, the complete set of genes as well as the structural-functional relationships of most of the enzymes involved in this process are still unknown. We have characterized a gene cluster (nic genes) from Pseudomonas putida KT2440 responsible for the aerobic NA degradation in this bacterium and when expressed in heterologous hosts. The biochemistry of the NA degradation through the formation of 2,5-dihydroxypyridine and maleamic acid has been revisited, and some gene products become the prototype of new types of enzymes with unprecedented molecular architectures. Thus, the initial hydroxylation of NA is catalyzed by a two-component hydroxylase (NicAB) that constitutes the first member of the xanthine dehydrogenase family whose electron transport chain to molecular oxygen includes a cytochrome c domain. The Fe(2+)-dependent dioxygenase (NicX) converts 2,5-dihydroxypyridine into N-formylmaleamic acid, and it becomes the founding member of a new family of extradiol ring-cleavage dioxygenases. Further conversion of N-formylmaleamic acid to formic and maleamic acid is catalyzed by the NicD protein, the only deformylase described so far whose catalytic triad is similar to that of some members of the alpha/beta-hydrolase fold superfamily. This work allows exploration of the existence of orthologous gene clusters in saprophytic bacteria and some pathogens, where they might stimulate studies on their role in virulence, and it provides a framework to develop new biotechnological processes for detoxification/biotransformation of N-heterocyclic aromatic compounds.Proceedings of the National Academy of Sciences 09/2008; 105(32):11329-34. · 9.68 Impact Factor -
Article: Identification and analysis of a glutaryl-CoA dehydrogenase-encoding gene and its cognate transcriptional regulator from Azoarcus sp. CIB.
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ABSTRACT: In this work, the gcdH gene from the denitrifying beta-proteobacterium Azoarcus sp. CIB was shown to encode a glutaryl-CoA dehydrogenase, which is essential for the anaerobic catabolism of many aromatic compounds and some alicyclic and dicarboxylic acids. The primary structure of the GcdH protein is highly conserved in many organisms. The divergently transcribed gcdR gene, encoding a LysR-type transcriptional regulator, accounts for the glutaconate/glutarate-specific activation of the Pg promoter driving expression of gcdH. The Azoarcus sp. CIBdgcdH mutant strain harbouring a disrupted gcdH gene was used as host to identify heterologous gcdH genes, such as that from Pseudomonas putida KT2440. Moreover, the expression of gcdH from P. putida can be efficiently controlled by the GcdR activator in Azoarcus sp. CIB, demonstrating the existence of cross-talk between GcdR regulators and gcdH promoters from members of different phylogenetic subgroups of proteobacteria.Environmental Microbiology 03/2008; 10(2):474-82. · 5.84 Impact Factor -
Article: New insights into the BzdR-mediated transcriptional regulation of the anaerobic catabolism of benzoate in Azoarcus sp. CIB.
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ABSTRACT: The expression of the bzd genes involved in the anaerobic degradation of benzoate in Azoarcus sp. CIB is controlled by the specific BzdR transcriptional repressor at the P(N) promoter. This catabolic promoter is also subject to catabolite repression by some organic acids. In vivo and in vitro experiments have shown that BzdR behaves as a repressor of the P(R) promoter by overlapping the transcription initiation site as well as the -35 and -10 boxes, benzoyl-CoA being the inducer molecule. In addition, by using a P(N) : : lacZ fusion both in Azoarcus sp. CIB and in an isogenic strain lacking the bzdR gene, we have shown that the succinate-dependent catabolite repression requires participation of the BzdR repressor.Microbiology 02/2008; 154(Pt 1):306-16. · 3.06 Impact Factor -
Article: Characterization of the last step of the aerobic phenylacetic acid degradation pathway.
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ABSTRACT: Phenylacetic acid (PA) degradation in bacteria involves an aerobic hybrid pathway encoded by the paa gene cluster. It is shown here that succinyl-CoA is one of the final products of this pathway in Pseudomonas putida and Escherichia coli. Moreover, in vivo and in vitro studies revealed that the paaE gene encodes the beta-ketoadipyl-CoA thiolase that catalyses the last step of the PA catabolic pathway, i.e. the thiolytic cleavage of beta-ketoadipyl-CoA to succinyl-CoA and acetyl-CoA. Succinyl-CoA is suggested as a common final product of aerobic hybrid pathways devoted to the catabolism of aromatic compounds.Microbiology 03/2007; 153(Pt 2):357-65. · 3.06 Impact Factor -
Article: Genetic characterization of the phenylacetyl-coenzyme A oxygenase from the aerobic phenylacetic acid degradation pathway of Escherichia coli.
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ABSTRACT: We show here that the paaABCDE genes of the paa cluster responsible for phenylacetate degradation in Escherichia coli W encode a five-component oxygenase that hydroxylates phenylacetyl-coenzyme A (CoA), the first intermediate of the pathway. The primary structure of the subunits of bacterial phenylacetyl-CoA oxygenases revealed that these enzymes constitute the prototype of a new and distinct group of the large bacterial diiron multicomponent oxygenase family.Applied and Environmental Microbiology 12/2006; 72(11):7422-6. · 3.83 Impact Factor -
Article: Coregulation by phenylacetyl-coenzyme A-responsive PaaX integrates control of the upper and lower pathways for catabolism of styrene by Pseudomonas sp. strain Y2.
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ABSTRACT: The P(styA) promoter of Pseudomonas sp. strain Y2 controls expression of the styABCD genes, which are required for the conversion of styrene to phenylacetate, which is further catabolized by the products of two paa gene clusters. Two PaaX repressor proteins (PaaX1 and PaaX2) regulate transcription of the paa gene clusters of this strain. In silico analysis of the P(styA) promoter region revealed a sequence located just within styA that is similar to the reported PaaX binding sites of Escherichia coli and the proposed PaaX binding sites of the paa genes of Pseudomonas species. Here we show that protein extracts from some Pseudomonas strains that have paaX genes, but not from a paaX mutant strain, can bind and retard the migration of a P(styA) specific probe. Purified maltose-binding protein (MBP)-PaaX1 fusion protein specifically binds the P(styA) promoter proximal PaaX site, and this binding is eliminated by the addition of phenylacetyl-coenzyme A. The sequence protected by MBP-PaaX1 binding was defined by DNase I footprinting. Moreover, MBP-PaaX1 represses transcription from the P(styA) promoter in a phenylacetyl-coenzyme A-dependent manner in vitro. Finally, the inactivation of both paaX gene copies of Pseudomonas sp. strain Y2 leads to a higher level of transcription from the P(styA) promoter, while heterologous expression of the PaaX1 in E. coli greatly decreases transcription from the P(styA) promoter. These findings reveal a control mechanism that integrates regulation of styrene catabolism by coordinating the expression of the styrene upper catabolic operon to that of the paa-encoded central pathway and support a role for PaaX as a major regulatory protein in the phenylacetyl-coenzyme A catabolon through its response to the levels of this central metabolite.Journal of Bacteriology 08/2006; 188(13):4812-21. · 3.83 Impact Factor -
Article: Oxygen-dependent regulation of the central pathway for the anaerobic catabolism of aromatic compounds in Azoarcus sp. strain CIB.
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ABSTRACT: The role of oxygen in the transcriptional regulation of the PN promoter that controls the bzd operon involved in the anaerobic catabolism of benzoate in the denitrifying Azoarcus sp. strain CIB has been investigated. In vivo experiments using PN::lacZ translational fusions, in both Azoarcus sp. strain CIB and Escherichia coli cells, have shown an oxygen-dependent repression effect on the transcription of the bzd catabolic genes. E. coli Fnr was required for the anaerobic induction of the PN promoter, and the oxygen-dependent repression of the bzd genes could be bypassed by the expression of a constitutively active Fnr* protein. In vitro experiments revealed that Fnr binds to the PN promoter at a consensus sequence centered at position -41.5 from the transcription start site overlapping the -35 box, suggesting that PN belongs to the class II Fnr-dependent promoters. Fnr interacts with RNA polymerase (RNAP) and is strictly required for transcription initiation after formation of the RNAP-PN complex. An fnr ortholog, the acpR gene, was identified in the genome of Azoarcus sp. strain CIB. The Azoarcus sp. strain CIB acpR mutant was unable to grow anaerobically on aromatic compounds and it did not drive the expression of the PN::lacZ fusion, suggesting that AcpR is the cognate transcriptional activator of the PN promoter. Since the lack of AcpR in Azoarcus sp. strain CIB did not affect growth on nonaromatic carbon sources, AcpR can be considered a transcriptional regulator of the Fnr/Crp superfamily that has evolved to specifically control the central pathway for the anaerobic catabolism of aromatic compounds in Azoarcus.Journal of Bacteriology 05/2006; 188(7):2343-54. · 3.83 Impact Factor -
Article: Growth phase-dependent expression of the Pseudomonas putida KT2440 transcriptional machinery analysed with a genome-wide DNA microarray.
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ABSTRACT: Bacterial transcriptional networks are built on a hierarchy of regulators, on top of which lie the components of the RNA polymerase (in particular the sigma factors) and the global control elements, which play a pivotal role. We have designed a genome-wide oligonucleotide-based DNA microarray for Pseudomonas putida KT2440. In combination with real-time reverse transcription polymerase chain reaction (RT-PCR), we have used it to analyse the expression pattern of the genes encoding the RNA polymerase subunits (the core enzyme and the 24 sigma factors), and various proteins involved in global regulation (Crc, Lrp, Fur, Anr, Fis, CsrA, IHF, HupA, HupB, HupN, BipA and several MvaT-like proteins), during the shift from exponential growth in rich medium into starvation and stress brought about by the entry into stationary phase. Expression of the genes encoding the RNA polymerase core and the vegetative sigma factor decreased in stationary phase, while that of sigma(S) increased. Data obtained for sigma(N), sigma(H), FliA and for the 19 extracytoplasmic function (ECF)-like sigma factors suggested that their mRNA levels change little upon entry into stationary phase. Expression of Crc, BipA, Fis, HupB, HupN and the MvaT-like protein PP3693 decreased in stationary phase, while that of HupA and the MvaT-like protein PP3765 increased significantly. Expression of IHF was indicative of post-transcriptional control. These results provide the first global study of the expression of the transcriptional machinery through the exponential stationary-phase shift in P. putida.Environmental Microbiology 02/2006; 8(1):165-77. · 5.84 Impact Factor -
Article: Iron-reducing bacteria unravel novel strategies for the anaerobic catabolism of aromatic compounds.
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ABSTRACT: Although the aerobic degradation of aromatic compounds has been extensively studied in many microorganisms, the anaerobic mineralization of the aromatic ring is a more recently discovered microbial capacity on which very little information is available from facultative anaerobic bacteria. In this issue of Molecular Microbiology, Wischgoll and colleagues use proteomic and reverse-transcription polymerase chain reaction (PCR) approaches to identify for the first time the gene clusters involved in the central pathway for the catabolism of aromatic compounds in Geobacter metallireducens, a strictly anaerobic iron-reducing bacterium. This work highlights that the major difference in anaerobic benzoate metabolism of facultative and strictly anaerobic bacteria is the reductive process for dearomatization of benzoyl-CoA. The authors propose that a new type of benzoyl-CoA reductase, comprising molybdenum- and selenocysteine-containing proteins, is present in strictly anaerobic bacteria. This work paves the way to fundamental studies on the biochemistry and regulation of this new reductive process and provides the first genetic clues on the anaerobic catabolism of benzoate by strict anaerobes.Molecular Microbiology 01/2006; 58(5):1210-5. · 5.01 Impact Factor
Top co-authors
Top Journals
Institutions
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2005–2013
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Centro de Investigaciones Biológicas
Madrid, Madrid, Spain
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2012
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University of Leipzig
Leipzig, Saxony, Germany
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2003–2011
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Spanish National Research Council
- Biological Research Centre
Madrid, Madrid, Spain
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2003–2006
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Complutense University of Madrid
- Departamento de Bioquímica y Biología Molecular II
Madrid, Madrid, Spain
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