Transcriptional Regulation of the Flavohemoglobin Gene for Aerobic Nitric Oxide Detoxification by the Second Nitric Oxide-Responsive Regulator of
            <i>Pseudomonas aeruginosa</i>

Arai, Hiroyuki; Hayashi, Michiko; Kuroi, Azusa; Ishii, Masaharu; Igarashi, Yasuo

doi:10.1128/jb.187.12.3960-3968.2005

Cited by 83 publications

(95 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here we describe possible coregulation of all denitrification genes in the Neisseria species by the nitrite-sensitive repressor NsrR. Recently, transcriptional regulation of the flavohemoglobin gene fhp (hmp ortholog) by the NO-responsive regulator FhpR (NorR ortholog) has been demonstrated in P. aeruginosa [51].…”

Section: Discussionmentioning

confidence: 99%

Dissimilatory Metabolism of Nitrogen Oxides in Bacteria: Comparative Reconstruction of Transcriptional Networks

Rodionov¹,

Dubchak²,

Arkin³

et al. 2005

PLoS Comp Biol

View full text Add to dashboard Cite

Bacterial response to nitric oxide (NO) is of major importance since NO is an obligatory intermediate of the nitrogen cycle. Transcriptional regulation of the dissimilatory nitric oxides metabolism in bacteria is diverse and involves FNRlike transcription factors HcpR, DNR, and NnrR; two-component systems NarXL and NarQP; NO-responsive activator NorR; and nitrite-sensitive repressor NsrR. Using comparative genomics approaches, we predict DNA-binding motifs for these transcriptional factors and describe corresponding regulons in available bacterial genomes. Within the FNR family of regulators, we observed a correlation of two specificity-determining amino acids and contacting bases in corresponding DNA recognition motif. Highly conserved regulon HcpR for the hybrid cluster protein and some other redox enzymes is present in diverse anaerobic bacteria, including Clostridia, Thermotogales, and delta-proteobacteria. NnrR and DNR control denitrification in alpha-and beta-proteobacteria, respectively. Sigma-54-dependent NorR regulon found in some gamma-and beta-proteobacteria contains various enzymes involved in the NO detoxification. Repressor NsrR, which was previously known to control only nitrite reductase operon in Nitrosomonas spp., appears to be the master regulator of the nitric oxides' metabolism, not only in most gamma-and beta-proteobacteria (including well-studied species such as Escherichia coli), but also in Gram-positive Bacillus and Streptomyces species. Positional analysis and comparison of regulatory regions of NO detoxification genes allows us to propose the candidate NsrRbinding motif. The most conserved member of the predicted NsrR regulon is the NO-detoxifying flavohemoglobin Hmp. In enterobacteria, the regulon also includes two nitrite-responsive loci, nipAB (hcp-hcr) and nipC (dnrN), thus confirming the identity of the effector, i.e. nitrite. The proposed NsrR regulons in Neisseria and some other species are extended to include denitrification genes. As the result, we demonstrate considerable interconnection between various nitrogen-oxides-responsive regulatory systems for the denitrification and NO detoxification genes and evolutionary plasticity of this transcriptional network.

show abstract

Section: Discussionmentioning

confidence: 99%

Dissimilatory Metabolism of Nitrogen Oxides in Bacteria: Comparative Reconstruction of Transcriptional Networks

Rodionov¹,

Dubchak²,

Arkin³

et al. 2005

PLoS Comp Biol

View full text Add to dashboard Cite

show abstract

“…For construction of pEX-⌬cyo, 0.9-and 1.4-kb fragments containing the upstream and downstream flanking regions of the cyoABCDE gene cluster, respectively, were amplified by PCR from PAO1ut chromosomal DNA using primer sets BoR1/BoR2 and BoR3/BoR4, respectively, and were then tandemly inserted into the EcoRI-BamHI and BamHI-PstI sites, respectively, of pEX18Ap (34). The resulting construct was digested with BamHI, blunt ended by the Klenow reaction, and then ligated with a blunt-ended SacI-excised fragment containing the tet-FRT cassette from pPS854tet (35), resulting in pEX-⌬cyo. pEX-⌬cco1 and pEX-⌬cco2 were constructed in the same manner using primer sets cbR3/cbR4 and cbR5/ cbR6 and primer sets cbR1/cbR2 and cbR3/cbR4, respectively.…”

Section: Methodsmentioning

confidence: 99%

“…The cyoABCDE, ccoN1O1Q1P1, and ccoN2O2Q2P2 gene clusters were knocked out using the Flp-FRT recombination system (34) with constructs pEX-⌬cyo, pEX-⌬cco1, and pEX⌬cco2, respectively, according to the method described previously (35). For construction of pEX-⌬cyo, 0.9-and 1.4-kb fragments containing the upstream and downstream flanking regions of the cyoABCDE gene cluster, respectively, were amplified by PCR from PAO1ut chromosomal DNA using primer sets BoR1/BoR2 and BoR3/BoR4, respectively, and were then tandemly inserted into the EcoRI-BamHI and BamHI-PstI sites, respectively, of pEX18Ap (34).…”

Section: Methodsmentioning

confidence: 99%

Enzymatic Characterization and In Vivo Function of Five Terminal Oxidases in Pseudomonas aeruginosa

et al. 2014

Self Cite

View full text Add to dashboard Cite

The ubiquitous opportunistic pathogen Pseudomonas aeruginosa has five aerobic terminal oxidases: bo 3 -type quinol oxidase (Cyo), cyanide-insensitive oxidase (CIO), aa 3 -type cytochrome c oxidase (aa 3 ), and two cbb 3 -type cytochrome c oxidases (cbb 3 -1 and cbb 3 -2). These terminal oxidases are differentially regulated under various growth conditions and are thought to contribute to the survival of this microorganism in a wide variety of environmental niches. Here, we constructed multiple mutant strains of P. aeruginosa that express only one aerobic terminal oxidase to investigate the enzymatic characteristics and in vivo function of each enzyme. The K m values of Cyo, CIO, and aa 3 for oxygen were similar and were 1 order of magnitude higher than those of cbb 3 -1 and cbb 3 -2, indicating that Cyo, CIO, and aa 3 are low-affinity enzymes and that cbb 3 -1 and cbb 3 -2 are high-affinity enzymes. Although cbb 3 -1 and cbb 3 -2 exhibited different expression patterns in response to oxygen concentration, they had similar K m values for oxygen. Both cbb 3 -1 and cbb 3 -2 utilized cytochrome c 4 as the main electron donor under normal growth conditions. The electron transport chains terminated by cbb 3 -1 and cbb 3 -2 generate a proton gradient across the cell membrane with similar efficiencies. The electron transport chain of aa 3 had the highest proton translocation efficiency, whereas that of CIO had the lowest efficiency. The enzymatic properties of the terminal oxidases reported here are partially in agreement with their regulatory patterns and may explain the environmental adaptability and versatility of P. aeruginosa.

show abstract

“…These transcription factors all belong to the cyclic AMP receptor protein/fumarate nitrate reductase regulator (FNR) family. In addition to DNR, P. aeruginosa has an NO-responsive, 54 -dependent transcriptional regulator, FhpR, which activates the flavohemoglobin gene (2). FhpR is homologous to NorR, a member of the NtrC family of response regulators, although phosphorylation does not play a role in activation of NorR, unlike many response regulators (32).…”

mentioning

confidence: 99%

The Nitric Oxide-Responsive Regulator NsrR Controls ResDE-Dependent Gene Expression

et al. 2006

View full text Add to dashboard Cite

The ResD-ResE signal transduction system is essential for aerobic and anaerobic respiration in Bacillus subtilis. ResDE-dependent gene expression is induced by oxygen limitation, but full induction under anaerobic conditions requires nitrite or nitric oxide (NO). Here we report that NsrR (formerly YhdE) is responsible for the NO-dependent up-regulation of the ResDE regulon. The null mutation of nsrR led to aerobic derepression of hmp (flavohemoglobin gene) partly in a ResDE-independent manner. In addition to its negative role in aerobic hmp expression, NsrR plays an important role under anaerobic conditions for regulation of ResDEcontrolled genes, including hmp. ResDE-dependent gene expression was increased by the nsrR mutation in the absence of NO, but the expression was decreased by the mutation when NO was present. Consequently, B. subtilis cells lacking NsrR no longer sense and respond to NO (and nitrite) to up-regulate the ResDE regulon. Exposure to NO did not significantly change the cellular concentration of NsrR, suggesting that NO likely modulates the activity of NsrR. NsrR is similar to the recently described nitrite-or NO-sensitive transcription repressors present in various bacteria. NsrR likely has an Fe-S cluster, and interaction of NO with the Fe-S center is proposed to modulate NsrR activity.

show abstract

Transcriptional Regulation of the Flavohemoglobin Gene for Aerobic Nitric Oxide Detoxification by the Second Nitric Oxide-Responsive Regulator of Pseudomonas aeruginosa

Cited by 83 publications

References 61 publications

Dissimilatory Metabolism of Nitrogen Oxides in Bacteria: Comparative Reconstruction of Transcriptional Networks

Dissimilatory Metabolism of Nitrogen Oxides in Bacteria: Comparative Reconstruction of Transcriptional Networks

Enzymatic Characterization and In Vivo Function of Five Terminal Oxidases in Pseudomonas aeruginosa

The Nitric Oxide-Responsive Regulator NsrR Controls ResDE-Dependent Gene Expression

Contact Info

Product

Resources

About