The natural oxide layer worked as an etching mask at 25 min. While the heights of the pre-processed areas were exactly the same as those before etching, the area

pre-processed at 40-μN load was enlarged by the plastic deformation.Figure  12 shows the topography and cross-sectional profiles of the pre-processed areas after 30-min etching. The etching also advanced in the unprocessed area. The etching depth of the area processed at 1.5 μN progressively increased to 210 nm, while that of the unprocessed area increased to 140 nm. This implied that only the Selleck Pevonedistat high-loaded processed area was not etched because of the mechanochemical oxide layer. The height obtained RG-7388 order at 10-μN load was slightly higher than that at 40-μN load.Figure  13 shows the etching profile of pre-processed areas after 40-min etching. The etching depths of both the low-load processed and unprocessed areas were approximately 530 nm. In contrast, the areas processed at high loads of 10 and 40 μN were not etched. This experimentally confirmed that high-loaded processed protuberate areas show superior etching resistance towards

KOH solution due to formation of a high-density OSI-906 purchase oxide layer.Figure  14 shows the dependence of relative etching depth on KOH solution etching time. The standard plane is the unprocessed area. The plane heights of the areas pre-processed at 10- and 40-μN load from the standard plane are denoted as A and B. The corresponding height of the area pre-processed at 1.5-μN load is C. Between 10 and 20 min, there was little change in the topography of each area. From 25- to 30-min etching, it was observed that the etched depths significantly increased in the 1.5-μN-load pre-processed area. However, etching was hardly observed in the 10- and 40-μN-load

pre-processed areas. Etching of the unprocessed area was hardly observed until 25 min. After 30-min etching, the unprocessed area was progressively etched owing to the removal of the natural oxide layer. Figure 10 Etching profile of processed parts after 20 min. (a) Surface profile. (b) Section profile (10 and 40 μN). Figure 11 Etching profile of processed parts after 25 min. (a) Surface profile. (b) Section RVX-208 profile (10 and 40 μN). Figure 12 Etching profile of processed parts after 30 min. (a) Surface profile. (b) Section profile (10 and 40 μN). Figure 13 Etching profile of processed parts after 40 min. (a) Surface profile. (b) Section profile. Figure 14 Dependence of relative etching depth on etching time at different loads. From 35 to 40 min, the etching depths of both the unprocessed and 1.5-μN-load pre-processed areas were larger than those of the areas processed at higher load. The area mechanically pre-processed at higher load exhibited resistance to etching owing to mechanochemical oxidation layer formation.

Moreover a clear separation between above-ground (stem and leaves) and below-ground environments (soil and nodules) was detected. An analysis of the clone libraries, prepared from above-ground and below-ground pooled samples, revealed an uneven distribution of bacterial classes, with a marked pattern highlighting the class of Alphaproteobacteria as the more abundant in plant tissues (this class represented

half of the clones in the stem + leaf library). The same uneven pattern Selleckchem Torin 1 was then observed, at lower taxonomic ranks, within the Alphaproteobacteria, with sequences of clones belonging to members of the Methylobacteriaceae and Sphingomonadaceae families being more abundant in stem than in soil and nodules. Methylobacteria and Sphingomonadaceae have been found as endophytes in a number of plants [8, 12, 31, 33, 42–45] and it is believed that this group of bacteria may take advantage from living as plant-associated, thanks to its ability to utilize the one-carbon alcohol methanol discharged by wall-associated pectin metabolism of growing plant cells. Concerning root nodule bacterial communities, obtained

data indicated that very diverse CYC202 order bacterial taxa are associated with nodules, the most represented being the specific rhizobial host of M. sativa, the alphaproteobacterium S. meliloti. However, additional taxa have been found, including members of Actinobacteria Flavobacteria Gammaproteobacteria and Betaproteobacteria, which may have some additional plant growth-promoting activities (see for

instance [46, 47]). In soil, Paclitaxel Acidobacteria was one of the most important divisions (in terms of number of clones in the library) and was present exclusively in the soil clone library, in agreement with many previous observations [48, 49]. A relatively high presence of Archaea (Thermoprotei) was also found. Checking the 16 S rRNA gene sequences present in the Ribosomal Database for 799f/pHr primer annealing, we found that PCR amplification from Thermoprotei was theoretically possible with this primer pair (data not shown). The presence of Archaea in the soil is not unexpected [50] and could be linked also to the anoxic or nearly anoxic conditions present in the bottom of the pot. However, since the low coverage of soil clone library, the presence of many other additional taxa, as well of different proportions of those found here cannot be excluded. In addition, it should be mentioned that differences between soil and Akt inhibitor plant-tissues bacterial communities could also be ascribed to the different DNA extraction protocols we were obliged to use, since a unique protocol (bead-beading protocol for both soil DNA and plant DNA) failed in a successful extraction of DNA from both soil and plant tissues (data not shown). A similar technical need was encountered by other authors also [33], which renders the study of the relationships between plant-associated and soil bacterial communities still at its beginning.

IRM supervised the design of the study. FJA led the design of the study and helped to draft the manuscript. All authors read and approved the final manuscript.”
“Background Magnetic

nanoparticles are a topic of growing interest because of their versatile applications such as drug delivery, SN-38 cell line magnetic hyperthermia, magnetic separation, magnetic resonance imaging (MRI) contrast enhancement, and ultrahigh-density data ROCK inhibitor storage [1–14]. Among those, magnetic hyperthermia is a novel therapeutic method in which the magnetic nanoparticles are subjected to an alternating magnetic field to generate a specific amount of heat to raise the temperature of a tumor to about 42°C to 46°C at which certain mechanisms of cell damage are activated [15, 16]. These mechanisms which produce heat in alternating current (AC) magnetic fields include the following: (1) hysteresis, (2) Neel or Brownian relaxation, and (3) viscous losses [17]. The generated heat is quantitatively described by the specific absorption rate (SAR) Cl-amidine in vivo of nanoparticles which is related to specific loss per cycle of hysteresis loop (A) by the equation SAR = A × f in which f is the frequency of the applied field. There are four models based on size regimes to describe the magnetic properties of nanoparticles [17]: 1. At superparamagnetic

size regime in which the hysteresis area is null, the equilibrium functions are used. In this size range depending on the anisotropy energy, the magnetic behavior of nanoparticles progressively changes from the Langevin function (L(ξ) = coth(ξ) - 1/ξ) for zero anisotropy to tanh(ξ) for maximal anisotropy where ξ = (μ 0 M s VH max)/(k B T).   2. Around the superparamagnetic-ferromagnetic transition size, the linear response theory (LRT) does the job for

us. The LRT is a model for describing the dynamic magnetic properties of an assembly of nanoparticles using the Neel-Brown relaxation time and assumes a linear relation between PtdIns(3,4)P2 magnetization and applied magnetic field. The area of the hysteresis loop is determined by [17] (1) where σ = KV/k B T, ω = 2πf, and τ R is the relaxation time of magnetization which is assumed to be equal to the Neel-Brown relaxation time (τ N).   3. In the single-domain ferromagnetic size regime, the Stoner-Wohlfarth (SW)-based models are applied which neglect thermal activation and assume a square hysteresis area that is practically valid only for T = 0 K or f → ∞ but indicates the general features of the expected properties for other conditions. Based on the SW model for magnetic nanoparticles with their easy axes randomly oriented in space, the hysteresis area is calculated by [17] (2)   4. Finally, for multi-domain ferromagnetic nanoparticles, there is no simple way to model the magnetic properties of such large nanoparticles. In hyperthermia experiments, increasing the nanoparticle size to multi-domain range promotes the probability of precipitation of nanoparticles which leads to the blockage of blood vessels.

This suggested the presence of a terminator or other regulatory sequence in the intergenic

region that modulated the expression of gluQ-rs. Figure 3 The transcription of the gluQ-rs gene is controlled by a termination stem loop. A) Schematic representation of the operon, the arrows indicate the position of each promoter identified by our bioinformatics analysis and experimentally determined by Kang and Craig, 1990 [22]. The putative ρ-independent terminator is represented by the stem loop symbol upstream of gluQ-rs gene. The horizontal bar represents the DNA region amplified and cloned into pQF50 (Table 1). The recombinant plasmids are described in Table 1. pVCDT does not have the dksA promoter but has the terminator. pVCPDT has the promoter region of dksA and the terminator upstream of gluQ-rs; therefore, it represents the genomic organization of the operon. pVCPD also has the promoter of dksA but lacks Ivacaftor concentration the terminator region. The size of each fragment is indicated. B) β-galactosidase activity of each protein extract obtained from the corresponding clone. The data represent the average of three experiments in triplicates and the Student buy Rabusertib t test was used to compare the means between each clone with the

empty vector. *** p values <0.05 were considered statistically significant. Table 1 Bacterial strains and plasmids used in this work Bacterial strains or plasmid Characteristics Source or reference Shigella flexneri     S. flexneri 2457T Wild type strain Laboratory stock S. flexneri 2457T ΔgluQ-rs::kan Deletion mutant of gluQ-rs gene This work Escherichia coli     E. coli W3110 ΔgluQ-rs::kan Deletion mutant of gluQ-rs gene [10] DH5α F - ϕ80lacZΔM15 Δ(lacZYA-argF) U169 recA1 endA1 hsdR17 (rK-, mK+) phoA supE44 λ-thi-1 gyrA relA1 [24] BL21(DE3) F - ompT gal dcm lon hsdS B (r B - m B - ) λ(DE3 [lacI lacUV5-T7 gene 1 ind1 sam7 nin5]) Invitrogen Plasmids     pTZ57R/T bla, pMB1 ori, lacZ peptide, f1 phage ori Fermentas® pQF50 bla, pMB1

ori, lacZ gene without promoter [23] pET15c Empty vector, a modified version of pET15b This work pVCDT S. flexneri fragment from check details nucleotide +58a of dksA gene to beginning of gluQ-rs gene (+590) cloned into pQF50. Pair of primers used were PgluQF/PdksARCT. This work pVCPDT S. flexneri fragment from nucleotide −506 of dksA Morin Hydrate gene to beginning of gluQ-rs gene (+590) cloned into pQF50. Pair of primers used were PdksAF/PdksARCT. This work pVCPDTMut S. flexneri fragment from nucleotide −506 of dksA gene to beginning of gluQ-rs gene (+590) cloned into pQF50, with the terminator mutated by the nucleotides indicated in Figure 4a. This work pVCPD S. flexneri fragment from nucleotide −506 of dksA gene to nucleotide +527 (end of dksA gene) cloned into pQF50. Pair of primers used were PdksAF/PdksARST. This work pATGGQRS S. flexneri gene from nucleotide +509 (stop codon of dksA) to nucleotide +1469 (last codon of gluQ-rs without stop codon). Pair of primers used were ATGGQRSF/ATGGQRSR.

Cary for her diligent bibliographic work in compiling the majority of the references. Fruitful discussion and comments on the manuscript were provided by E. Leger, T. Rand, A. Dyer, J. Gaskin, K. Rice, and the V. Eviner lab. We also thank two anonymous reviewers whose comments substantially improved the manuscript.

Appendix See Table 6. Table 6 Dataset and references for the statistical analysis Species name Family Geographic rangea (GR) Habitat specificityb (HS) Local abundancec (LA) Life history Pollination syndrome Dispersal (biotic/abiotic) Specific dispersal Mating system Referenced Acacia ausfeldii Fabaceae S S D Perennial   Biotic Ant   Brown et al. ( 2003 ) BEZ235 Acacia sciophanes Fabaceae S G S Perennial Biotic     Mixed Coates et al. ( 2006 ) Acacia williamsonii Fabaceae S S D Perennial   Biotic Ant   Brown et al. ( 2003 ) Agrostis hiemalis Poaceae

L G S Perennial         Rabinowitz and Rapp CYT387 (1979) and Rabinowitz and Rapp ( 1985 ) Alchemilla fontqueri Rosaceae S S S Perennial Abiotic Abiotic Wind Mixed Blanca et al. ( 1998 ) and Baudet et al. (2004) Alyssum nevadense Brassicaceae S G S Perennial Biotic Abiotic Ballistic   Blanca et al. ( 1998 ), Melendo et al. (2003) and Ivorra (2007) Arenaria nevadensis click here Caryophyllaceae S S S Annual Biotic Abiotic Ballistic Sexual Blanca et al. ( 1998 ), Melendo et al. (2003), Baudet et al. (2004), and Lopez-Flores et al. (2008) Armeria filicaulis subsp. trevenquiana Plumbaginaceae S S

S Perennial Biotic Both   Asexual Blanca et al. ( 1998 ), Melendo et al. (2003) and Baudet et Enzalutamide molecular weight al. (2004) Artemisia alba subsp. nevadensis Asteraceae S G S Perennial Abiotic Abiotic Ballistic   Blanca et al. ( 1998 ) and Melendo et al. (2003) Artemisia granatensis Asteraceae S G S Perennial Abiotic Abiotic   Asexual Blanca et al. ( 1998 ), Melendo et al. (2003), and Baudet et al. (2004) Artemisia umbelliformis Asteraceae L G S Perennial         Blanca et al. ( 1998 ) and USDA PLANTS Database (2009) Betula pendula subsp. fontqueri Betulaceae L S S Perennial         Blanca et al. ( 1998 ) and Flora Iberica (2009) Boopis gracilis Calyceraceae L S D Annual         Ghermandi et al. ( 2004 ) Brassica insularis Brassicaceae S S S Perennial Biotic     Sexual Hurtrez Bousses ( 1996 ) and Glemin et al. (2008) Centaurea gadorensis Asteraceae S G S Perennial Biotic Biotic Ant   Blanca et al. ( 1998 ), Melendo et al. (2003) and Lorite et al. (2007) Cephalanthera rubra Orchidaceae L G S Perennial Biotic     Mixed Blanca et al. ( 1998 ) and Brzosko and Wroblewska (2003) Chenopodium scabricaule Chenopodiaceae L S D Perennial         Ghermandi et al.

Thus, electrostatic repulsions between this website N- and C-terminal domains force the protein into the “”open”" position. This in turn releases the N-terminal domain,

forming a stable complex with KdpE~P and the DNA [25] initiating kdpFABC expression. Replacement of the KdpD-Usp domain with UspF or UspG results in inversion of the surface net charges. The negative net surface charge of these two proteins forces electrostatic attraction between the N- and the C-terminal regions, leaving KdpD in the “”OFF”" state under all conditions. Conclusion The Usp domain within KdpD is important for proper KdpD/KdpE signaling. Alterations within this domain can completely prevent the response towards K+ limitation as well as salt stress. The KdpD-Usp domain surface contains numerous positively charged amino acids. Electrostatic repulsion and attraction between the N-terminal and C-terminal domain are supposed to be important for KdpD (de)activation. Therefore, www.selleckchem.com/products/forskolin.html the KdpD-Usp domain not only functions as a binding surface for the native scaffold UspC, but also seems to be crucial

for internal KdpD signaling, shifting the protein from an “”OFF”" into an “”ON”" state. Methods Materials [γ32-P]ATP and NAP-5 gel filtration columns were purchased from Amersham GE Healthcare. Goat anti-(rabbit IgG)-alkaline phosphatase was purchased from Biomol. All other reagents were reagent grade and obtained from commercial sources. Bacterial strains and plasmids E. coli strain JM 109 [recA1 endA1 gyrA96 thi hsdR17 supE44λrelA1 Δ(lac-proAB)/F'traD36 proA + B + lacI q lacZΔM15] C1GALT1 [30] was used as carrier for the plasmids Selleckchem MM-102 described. E. coli strain TKR2000 [ΔkdpFABCDE trkA405 trkD1 atp706] [31] containing different

variants of plasmid pPV5-3 encoding the different KdpD-Usp derivatives (see below) was used for expression of the kdp-usp derivatives from the tac promoter. E. coli strain HAK006 [ΔkdpABCD Δ(lac-pro) ara thi] [32] carrying a kdpFABC promoter/operator-lacZ fusion was used to probe signal transduction in vivo. E. coli LMG194 [F- ΔlacX74 galE galK thi rpsL ΔphoA (PvuII) Δara714leu::Tn10] [33] was used for expression of the kdp-usp derivatives from the araBAD promoter. To replace the Usp domain in E. coli KdpD with the E. coli Usp protein sequences, the corresponding usp genes were PCR amplified using genomic DNA of E. coli MG1655 [34] as a template. The uspA, uspD, uspE, uspF, and uspG genes were amplified with primers complementary at least 21 bp to the 5′ or the 3′ ends of the corresponding genes with overhangs for a 5′ NsiI site and a 3′ SpeI site, respectively. uspC was amplified similarly, but with a 5′ terminal SacI site.

Figure 5 Survival of wildtype and CovS mutants in whole blood. The multiplication factor for each CovS mutant strain is shown as percentage from the data obtained with the corresponding wild type strain, CH5183284 purchase which was set to 100% for each independent test. The data represent the mean values and standard deviations from two independent sets of experiments using blood from three different donors. *, indicates significance level for differences between wildtype and isogenic mutant strains as calculated by the two-tailed paired Student’s t test. Discussion Lately, an increasing amount of data compile to a strong

argument for a strain-dependent transcriptional regulation in GAS. In addition, a comparison of the set of genes regulated by CovRS in different Streptococcus agalactiae LY2835219 purchase (Group B streptococci, GBS) strains revealed variations in their CovRS regulons. Thus, a strain-specific manner of CovRS-mediated gene regulation in GBS was reported [34]. In this study,

we investigated the potential effect of the sensor kinase CovS on virulence traits of different S. pyogenes serotypes strains, in order to figure out if a serotype- or strain-dependent influence of CovS regulation in GAS does occur in the genetic background of an intact response regulator CovR. Although CovRS has been described as a global regulatory system in GAS, our results clearly showed that variations of the CovS effect on selleck chemicals biofilm formation appear and that strain-dependent diversity in the CovRS regulons might Fenbendazole exist also in GAS. Biofilm production

has been described recently as an important protective mechanism of GAS associated with increased antibiotic resistance [17]. Previously, Cho and Caparon [18] showed that a M6 mutant lacking CovR failed to form biofilms, which suggests that the CovRS TCS is required for biofilm formation in GAS. Surprisingly, in contrast to the latter observation, our investigation showed that the CovS inactivation in other M6 strains did not lead to the same result. This statement implied that CovS might be involved in a strain-dependent influence on biofilm formation. Alternatively, since our mutant is deficient of CovS, but not CovR, the observed contradiction could be indicative of divergent influence of the response regulator CovR and histidine kinase CovS on biofilm formation. Another explanation supported by a previous study by Dalton and Scott suggested a direct or indirect influence of CovS on CovR under mild stress conditions [35]. Such stress conditions could have an influence on S. pyogenes biofilm growth. Further experiments presented here on the biofilm production of different GAS serotypes strains showed that the CovS influence on biofilm of GAS is a strain-dependent characteristic. This heterogeneity among different isolates could be associated with adaptation to diverse host environments.

The results provide more detailed insight into the human GI microbiota especially in the context of the diversity of high %G+C bacteria, i.e. Actinobacteria. Results Percent guanine plus cytosine -profiling, cloning and sequencing

To analyse the diversity of the healthy human intestinal microbiota, a %G+C profiled and fractionated (Figure 1) find more pooled faecal bacterial DNA sample of 23 individuals was cloned, and the partial 16S rRNA genes were sequenced. Nutlin-3a The previously published 976 sequences from three %G+C fractions (%G+C 25–30, 40–45 and 55–60) [21] were combined with the 2223 new sequences cloned in this study (%G+C fractions 30–35, 35–40, 45–50, 50–55, 60–65, 65–70 and 70–75) for phylogenetic and statistical analyses of the complete %G+C profile ranging from 25% G+C Selleck JQ1 to 75% G+C (Figure 1, Table 1). Altogether, 3199 sequences encompassing approximately 450 bp from the 5′-end of the 16S rRNA gene, covering two variable areas V1 and V2, were sequenced from all clones from the fractioned sample. For comparison, 459 clones were sequenced from an unfractioned pooled faecal bacterial DNA sample originating from the same individuals. Table 1 Characteristics of the sequence libraries.

Library(s) Sequences (no.) OTUs (no.)a %G+Cb Singletons (no.) Coveragec Fr G+C 25–30% 319 91 51.5 43 87 Fr G+C 30–35% 350 94 52.6 48 86 Fr G+C 35–40% 313 93 53.4 50 84 Fr G+C 40–45% 346 119 53.9 67 81 Fr G+C 45–50% 316 112 56.0 62 80 Fr G+C 50–55% 292 62 58.1 22 93 Fr G+C 55–60% 311 45 62.1 22 93 Fr G+C 60–65% 303 64 61.7 26 91 Fr G+C 65–70% 362 130 57.6 65 82 Fr G+C 70–75% 287 116 55.5 67 77 Fr G+C 25–75%d 3199 455 56.2 180 94 Unfractioned 459 131 53.6 66 86 a. The number of OTUs determined with DOTUR using 98% similarity criterion [53] b. Average %G+C content of the partial 16S rRNA gene sequences c. Coverage according to Good [23] d. The combined G+C fractions Figure 1 Percent guanine plus cytosine profile of intestinal microbial genomic DNA pooled from 23 healthy subjects. The amount of DNA

is indicated as relative absorbance (%) and the area under the curve is used for calculating the proportional amount of DNA in the separate fractions (modified from Kassinen et al. [21]). Determination of operative taxonomic units and library coverage tuclazepam The quality-checked 3199 sequences from the combined fractioned sample libraries represented 455 operative taxonomic units (OTUs), and the 459 sequences from the unfractioned sample represented 131 OTUs with a 98% similarity criterion (Table 1). All novel OTUs with less than 95% sequence similarity to public sequence database entries were further sequenced to near full-length (Additional file 1). The coverages of the individual clone libraries of the fractioned sample ranged from 77% to 93%, while the coverage for the unfractioned sample was 86% [23] (Table 1).

d Myriotrema album. e Ocellularia permaculata. f Redingeria glaucoglyphica. g Reimnitzia santensis. h Stegobolus radians The taxonomy of this clade will be dealt with in a separate paper (Rivas Plata et al. 2011b). Thelotremateae Rivas Plata, Lücking and Lumbsch, trib. nov. MycoBank 563413 Tribus novum ad Graphidoideae in Graphidaceae pertinens. Ascomata rotundata vel rare elongata, immersa vel sessilia. Excipulum hyalinum vel rare carbonisatum. Hamathecium non-amyoideum

learn more et asci non-amyloidei. Ascospori transversaliter septati vel muriformes, incolorati vel fusci, amyloidei vel non-amyloidei, lumina lenticulari vel rectangulari. Acidi lichenum variabili sed acidum sticticum et acidum norsticticum communi. Type: Thelotrema Ach. Ascomata rounded to rarely elongate, immersed to sessile. Excipulum hyaline to rarely carbonized, usually paraplectenchymatous. Periphysoids often present, sometimes with warty tips. Columellar structures

usually absent. Hamathecium and asci non-amyloid; paraphyses sometimes with warty tips. Ascospores transversely septate to muriform, colorless to (grey-)brown, amyloid to non-amyloid, septa thickened or reduced, lumina lens-shaped to rectangular. Secondary chemistry variable but stictic and norstictic acids predominant. Genera included see more in tribe (14): Acanthothecis Clem., Acanthotrema Frisch, Carbacanthographis Staiger and Kalb, Chapsa A. Massal., Chroodiscus (Müll. Arg.) Müll. Arg., Diploschistes Norman, Heiomasia Nelsen, Lücking and Rivas Plata, Leucodecton A. Massal.,

Melanotopelia Lumbsch and Mangold, Nadvornikia Tibell, Schizotrema Mangold Acyl CoA dehydrogenase and Lumbsch, Thelotrema Ach., Topeliopsis Kantvilas and Vězda, Wirthiotrema Rivas Plata, Kalb, Frisch and Lumbsch (Fig. 1). This clade includes over 300 currently IWR-1 order accepted species in 14 genera and is the morphologically most diverse and heterogeneous clade in the family (Fig. 8). It includes the unique genera Acanthothecis (lirellate ascomata with warty paraphyses), Diploschistes (on inorganic substrata with trebouxioid photobiont), Heiomasia (sterile with isidioid vegetative propagules), and Nadvornikia (mazaediate). The bulk of the clade corresponds to the genus Thelotrema sensu Hale (1980), now subdivided into several, partially unrelated linages (Thelotrema s.str., Acanthotrema, Chapsa, Chroodiscus, Schizotrema, Topeliopsis). Most of the currently delimited genera are well-supported as monophyletic, with the exception of Chapsa and Topeliopsis (unpubl. results, data not shown). The Nadvornikia lineage includes at least three non-mazaediate species previously classified as Myriotrema and Thelotrema by Hale (1980). Fig. 8 Selected species of Graphidoideae tribe Thelotremateae. a Acanthothecis subclavulifera. b Chapsa platycarpa. c Chroodiscus coccineus. d Diploschistes cinereocaesius. e Melanotopelia rugosa. f Nadvornikia hawaiiensis. g Thelotrema lepadinum.

Mol Microbiol 1993, 8:61–68.PubMedCrossRef 20. Khoroshilova N, Popescu C, Munck E, Beinert H, Kiley PJ: Iron-sulfur cluster disassembly

in the FNR protein of Escherichia coli by O 2 : [4Fe-4S] to [2Fe-2S] conversion with loss of biological activity. Proc Natl Acad Sci U S A 1997, 94:6087–6092.PubMedCentralPubMedCrossRef 21. Kiley PJ, Beinert H: CP673451 molecular weight oxygen sensing by the global regulator, FNR: the role of the iron-sulfur cluster. FEMS Microbiol Rev 1998, 22:341–352.PubMedCrossRef 22. Lazazzera BA, Beinert H, Khoroshilova N, Kennedy MC, Kiley PJ: DNA binding Selleck Peptide 17 and dimerization of the Fe-S-containing FNR protein from Escherichia coli are regulated by oxygen. J Biol Chem 1996, 271:2762–2768.PubMedCrossRef 23. Crack J, Green J, Thomson AJ: Mechanism of oxygen sensing by the bacterial transcription factor fumarate-nitrate reduction (FNR). J Biol Chem 2004, 279:9278–9286.PubMedCrossRef 24. Khoroshilova N, Beinert H, Kiley PJ: Association of a polynuclear iron-sulfur center with a mutant FNR protein enhances DNA binding. Proc Natl Acad Sci U S A AZD6244 mouse 1995, 92:2499–2503.PubMedCentralPubMedCrossRef 25. Lazazzera BA, Bates DM, Kiley PJ: The activity of the Escherichia coli transcription factor FNR is regulated by a change in oligomeric state. Genes Dev 1993, 7:1993–2005.PubMedCrossRef

26. Popescu CV, Bates DM, Beinert H, Munck E, Kiley PJ: Mössbauer spectroscopy as a tool for the study of activation/inactivation of the transcription regulator FNR in whole cells of Escherichia coli . Proc Natl Acad Sci U S A 1998, 95:13431–13435.PubMedCentralPubMedCrossRef 27. Jordan PA, Thomson AJ, Ralph ET, Guest JR, Green J: FNR is a direct oxygen sensor having a biphasic response curve. FEBS Lett 1997, 416:349–352.PubMedCrossRef 28. Sutton VR, Mettert EL, Beinert H, Kiley PJ: Kinetic analysis of the oxidative conversion of the [4Fe-4S] 2+

cluster of FNR to a [2Fe-2S] 2+ Cluster. J Bacteriol 2004, 186:8018–8025.PubMedCentralPubMedCrossRef 29. Ullrich S, Schüler D: Cre- lox -based method for generation of large deletions within the genomic magnetosome island of Magnetospirillum gryphiswaldense . Appl Environ Microbiol 2010, ID-8 76:2349–2444.CrossRef 30. Kiley PJ, Reznikoff WS: Fnr mutants that activate gene-expression in the presence of oxygen. J Bacteriol 1991, 173:16–22.PubMedCentralPubMed 31. Cruz-Garcia C, Murray AE, Rodrigues JLM, Gralnick JA, McCue LA, Romine MF, Loffler FE, Tiedje JM: Fnr (EtrA) acts as a fine-tuning regulator of anaerobic metabolism in Shewanella oneidensis MR-1. BMC Microbiol 2011, 11:64.PubMedCentralPubMedCrossRef 32. Bates DM, Popescu CV, Khoroshilova N, Vogt K, Beinert H, Munck E, Kiley PJ: Substitution of leucine 28 with histidine in the Escherichia coli transcription factor FNR results in increased stability of the [4Fe-4S] 2+ cluster to oxygen. J Biol Chem 2000, 275:6234–6240.PubMedCrossRef 33.