8) The intracellular replication of WT Salmonella and the comple

8). The intracellular replication of WT Salmonella and the complemented sseB strain was about 50- to 55-fold over a period of 14 h. The replication of the sseB strain without plasmid or with plasmids for the expression of any of the deletions alleles of sseB was reduced to an about 5-fold increase

of the intracellular bacteria and no significant difference between the various Selleckchem BLZ945 constructs was observed (Fig. 8A). Similar characteristics were observed for strains expressing deletion alleles of sseD and none of the mutant strains showed intracellular replication that was above the level of the sseD strain (Fig. 8B). Figure 8 Effect of mutations in SseB or SseD on intracellular replication of Salmonella. Macrophages were infected at a MOI of 1 with S. Typhimurium wild type (WT), sseB, sseB [psseB] or sseB harboring plasmids for expression of various sseB mutant alleles (sseB [psseBΔx]) (A), or WT, sseD, sseD [psseD], or various strains harboring chromosomal PF477736 deletion in sseD (B). Extracellular bacteria were killed by gentamicin treatment during 1 h post infection. Intracellular bacteria were quantified after host cell lysis with Triton X-100 at 2 h and 16 h post infection. The x-fold replication is the ratio of viable intracellular bacteria recovered at 16 h versus 2 h post infection. The replication rate

was assessed in triplicates and the standard deviation of the mean was calculated. Means and standard deviations of triplicate assays are shown and all experiments were performed at least twice. These data indicate that SseB and SseD do not tolerate major Selleckchem JNJ-26481585 alterations of the primary structure in order to fulfill their function as parts of the translocon selleck chemical of the SPI2-T3SS. The data also demonstrate that a fully functional translocon is required for the efficient intracellular replication. The residual ability of strains expressing sseBΔ2 or sseBΔ3 to translocate effector proteins appears to be insufficient to confer the ability of intracellular replication. Discussion In this

study we performed a structure-based functional dissection of the SPI2-T3SS translocon proteins SseB and SseD. Protein domains predicted as putative transmembrane regions or coiled-coil regions were deleted, as well as N- or C-terminal portions, and previously defined binding regions for the specific chaperone SseA [9, 10]. The deletional and functional analyses described here clearly demonstrate the sensitivity of SseB and SseD against structural alterations. Many of the deletion variants lost the ability to be secreted by the SPI2-T3SS. However, we also identified a subset of deletion variants that were synthesized in quantities similar to the WT proteins, secreted under in vitro conditions and bound to the bacterial surface. The lack of the chaperone binding site in SseB led to reduced amounts of protein. We found that some mutant forms of SseB were on surface structures on bacteria grown in vitro (Fig. 4B), but not on intracellular Salmonella (Fig. 5B).

Melting curve analysis was conducted

over a range of 55 t

Melting curve analysis was conducted

over a range of 55 to 95°C to assess specificity of amplification. Interleukin-8 expression was normalized to the housekeeper gene, C1orf33, and fold changes in expression relative to the sterile-broth control was calculated using the 2-ΔΔCT method. Statistical analysis Experiments were conducted at least three times on separate occasions selleck chemical (i.e., replicates). Each assay was conducted at least in duplicate (i.e., observations), and the mean value was used for analysis. Data are expressed as mean ± SEM. All statistical calculations were performed with GraphPad InStat v.3.06 software (GraphPad Software Inc., San Diego, CA). Data with three or more treatments were compared by one way analysis ATM Kinase Inhibitor manufacturer of variance, followed by the protected Tukey-Kramer multiple comparison test. Data with two treatments were compared using an unpaired Student’s t-test. Regression analysis was performed using Pearson correlation analysis. Statistical

significance was established at P < 0.05. Acknowledgements We thank Jenny Gusse for conducting the AFLP genotyping and cluster analysis, sequencing the 16S rRNA gene, and for designing and validating the C. concisus-specific cpn60 primers. We also thank Kathaleen House for isolating and conducting the initial characterization of C. concisus isolates. We wish to thank the anonymous reviewers of this manuscript for their insightful and constructive comments. This work was supported by a Peer Review Grant from Agriculture and Agri-Food Canada (Growing Forward initiative). Electronic supplementary material Additional file

1: Dendrogram of C. concisus AFLP profiles demonstrating reproducibility between duplicate independently-prepared samples. AFLP profiles were derived using the unweighted-pair group average linkage of Pearson-product-moment correlation coefficients from 22 Campylobacter Galactosylceramidase concisus fecal isolates (designated CHRB) and the type strain (LMG7788). The bar indicates percentage similarity. *, isolates for which only a single profile was analyzed. Additional file 1 contains a figure. (JPEG 111 KB) Additional file 2: Transepithelial resistance (TER) and FITC-dextran www.selleckchem.com/products/VX-765.html permeability for confluent, polarized T84 monolayers inoculated with Campylobacter concisus isolates a . Additional file 2 contains a table. (DOC 24 KB) Additional file 3: PCR screening of genes coding for cytolethal distending toxin (CDT), zonula occludens toxin (Zot), and S-layer RTX for Campylobacter concisus isolates. Additional file 3 contains a table. (DOC 22 KB) References 1. Aabenhus R, On SL, Siemer BL, Permin H, Andersen LP: Delineation of Campylobacter concisus genomospecies by amplified fragment length polymorphism analysis and correlation of results with clinical data. J Clin Microbiol 2005,43(10):5091–5096.PubMedCrossRef 2.

A laparoscopic approach was also envisaged It is currently encou

A laparoscopic approach was also envisaged. It is currently encouraged in emergency repair of complicated abdominal wall hernias [2]. However, this approach may prolong the time of operation and increase the risk of mortality in centers that have limited laparoscopic

experience and in patients having a bad general condition. Various repairs include primary suture of the orifice, muscle flaps, omentum, broad ligament, uterine fundus, prosthetic material and mesh plug. selleck chemicals Without repair, compications rates of approximately 25% are reported [1]. The use of mesh for repair of the strangulated hernias in which resection was performed is controversial [2]. Some authors do not recommend this type of repair due to the higher risk of rejection caused by infection. Others recommend it when an intestinal resection is carried out with sufficient care to minimize A-1155463 manufacturer infective complications; Barasertib order therefore, the use of mesh will not be contraindicated [2, 4, 9]. In our practice we don’t use prosthetic material in strangulated hernias and particularly like in this case where a bowell resection was performed. Mortality is reported to be between 10% and 50% in lumbar hernia. Unfavorable outcomes are commonly associated with delay in diagnosis and therapy, poor condition, elderly patients having coexistent diseases and strangulation with intestinal gangrene [1, 14]. Although lumbar hernias are rare, they should

be considered when an elderly, thin patient presents with a bowel obstruction. Early diagnosis and treatment are the most important factors in decreasing mortality and morbidity; therefore, rapid action for diagnosis and therapy is essential. Consent Written informed

consent was obtained from the patient for the publication of this report and any accompanying images. References 1. Suarez S, Hernandez JD: Laparoscopic repair of a lumbar hernia: report of a case and extensive review of the literature. Surg Endosc 2013,27(9):3421–3429.PubMedCrossRef 2. Sartelli M, Coccolini F, van Ramshorst GH, Campanelli G, Mandalà V, Ansaloni L, et al.: WSES guidelines for emergency repair of Montelukast Sodium complicated abdominal wall hernias. World J Emerg Surg 2013,8(1):50.PubMedCrossRef 3. Hume GH: Case of strangulated lumbar hernia. Br Med J 1889,2(1489):73.PubMedCentralPubMedCrossRef 4. Makhmudovos: Spontaneous rupture of strangulated lumbar hernia. Khirurgiia (Mosk) 1955, 2:67. 5. Millard DG: A richter’s hernia through the inferior lumbar triangle of petit: a radiographic demonstration. Br J Radiol 1959, 32:693–695.PubMedCrossRef 6. Florer RE, Kiriluk L: Petit’s triangle hernia incarcerated: two cases reported. Am Surg 1971, 37:527–530.PubMed 7. Ermakov MA, Vadiutina EV, Chentsova IV: Strangulated upper lumbar hernia. Vestn Khir Im I I Grek 1974,112(5):127.PubMed 8. Horovitz IL, Schwartz HA, Dehan A: A lumbar hernia presenting as an obstruction of the colon.

Growth conditions: overnight TY culture, diluted 100x in fresh TY

Growth conditions: overnight TY culture, diluted 100x in fresh TY grown to exponential phase in 37°C. Plasmolysis is at RT. The phase-contrast image (left) is also depicted inverted-negative (middle) to more clearly visualize the plasmolysis bays. The cells are grown in the presence of IPTG to induce expression of the construct. After staining with fluorescent Streptavidin, we find that the SA-1

peptide is properly exposed YAP-TEAD Inhibitor 1 in vitro on the cell surface (Figure 1A), suggesting that the OmpA TM domain is properly inserted in the OM, with the mCherry domain present in the periplasm. We used SDS-PAGE gel-shift experiments to check if the constructs are intact or suffer from degradation, and if so to what extent. These experiments make Mdm2 antagonist use of OmpA’s so-called heat modifiability [29]: In its folded form, OmpA migrates to a different position in SDS-PAGE compared to its (heat denatured) unfolded form [9, 10]. First, we checked for a possible heat-modifiability of mCherry, as it also has a β-barrel fold. To this end, we grew cells expressing cytoplasmic mCherry, lysed them by sonication, and after varying heat treatment, subjected the samples to SDS-PAGE followed by immunoblotting with a monoclonal antibody (anti-DsRed, LY2228820 Clontech) that recognizes only denatured

DsRed variants, including mCherry (Figure 1B). Thus, we make use of the antibody’s specificity for the unfolded state of mCherry to obtain information on its folding state after varying heat treatment conditions. A band of the expected height (27 kDa) was present that increased in intensity upon heating (the faint band above it was also present in lysate without mCherry), and did not exhibit heat-modifiability. The increase in intensity is explained by a gradual unfolding of mCherry due to increasing exposure to heat. If we assume that after boiling, all mCherry is unfolded, we then conclude based on band intensities that at RT i.e. without any heat treatment, ~80% of mCherry is folded and 20% is not. Since mCherry

unfolds partially under conditions where OmpA is fully stable (15 minutes at 50°C, [9]), we conclude that the mCherry β-barrel fold is less stable than that of the OmpA TM domain (Figure 1B). Therefore, the anti-DsRed can be used to determine the folding state of the OmpA TM domain, because the denatured mCherry will become visible Chlormezanone before OmpA has unfolded, and any gel-shifts observed can be unequivocally attributed to the OmpA TM domain, because mCherry itself becomes visible only after it has unfolded, and does not exhibit heat modifiability. To test the heat-modifiability of the OmpA-177-(SA-1)-mCherry fusion, an immunoblot containing cell lysates heated at different temperatures was probed with anti-DsRed (shown in Figure 1C). Starting at the far right lane (99°C), two bands are visible, a low and high molecular weight band (LMW and HMW respectively). At RT and 37°C, only a faint LMW (degradation) band at 26 kDa was detected.

This may be in part from chelation of divalent cations from catal

This may be in part from chelation of divalent cations from catalytic DNA-associated metalloproteins. Chelation as a mechanism has been observed as the effect of other compounds upon cancer. Sorenson and

Wanglia [7] reported tetrathiomolybdate chelates copper from proangiogenic molecules, thereby causing a reversible growth arrest in squamous cell carcinoma Acadesine (SCC) in vitro and caused by decreased vascular proliferation within the tumor bed. Conversely, chelation has also been shown to activate proangiogenic genes including vascular endothelial growth factor (VEGF) in other models [8]. We have also observed significant cytokine changes induced by FA and this may also explain the cytostatic or cytocidal effects of FA [9]. FA has demonstrated anti-tumorigenic activity in non-epidermoid carcinomas such as adenocarcinoma and hepatocellular carcinoma [6, 10]. Our data demonstrate a suppressive effect of FA upon two HNSCC (epidermoid) lines (Hep-2 and UMSCC-1) in vitro [11]. Additionally, in a docetaxel-resistant head and neck cancer cell line, FA demonstrates a concentration-driven suppression of cell growth [9]. The novel mechanism of FA provides an alternative to present therapies [9] as a single agent whether given parenterally or orally. It has synergy with conventional

agents taxol, carboplatin, and erlotinib. It has shown effect upon resistant cell lines in culture and in laboratory animals, which may offer the possibility of its use in the setting of treatment failure. Preliminary data show no evidence of toxicity at therapeutic doses. The efficacy and SNS-032 order potency of orally administered FA suggests that it would be practical as an ambulatory oral therapy [12, 13]. Potential applications of FA might include use as a second-line drug for patients who have failed first-line therapy, inhibition of growth of known metastatic carcinoma (chronic therapy), prophylactic therapy against recurrent or second primary disease given to high-risk patients (patients with the previous diagnosis of HNSCC), or as a first-line agent given in combination Roflumilast with another chemotherapy

using an alternative mechanism of action. We have accumulated substantial animal evidence to pursue phase I trials of FA in humans. These data suggest that an oral dose of 25 mg/kg per day is efficacious toward HNSCC in mice [11–13]. Prior to phase I clinical trials, the oral bioavailability of FA in an animal model must be evaluated to guide a phase I Selleck Talazoparib experimental design. In the study described here, the oral bioavailability was determined from the ratio of the area under the serum concentration–time curve following oral administration (AUCPO) to the area under the serum concentration–time curve following intravenous administration (AUCIV). The bioavailability was calculated from each animal since each received an IV dose and an oral (PO) dose.

Although no influence of SPIs on gut

colonisation was obs

Although no influence of SPIs on gut

colonisation was observed, SPI-1 and SPI-2 pathogeniCity islands were both required for S. Enteritidis colonisation of the liver and spleen, similar to previous studies [9, 13, 18, 21]. Interestingly, the decrease in counts of the ΔSPI1 and ΔSPI2 mutants in the liver and spleen was numerically not as high as that observed for single gene SPI-2 mutants in mice [22]. The importance of these two SPIs for S. Enteritidis colonisation of the liver and spleen of find more chickens was further supported by the behaviour of SPI1o and SPI2o mutants which, when compared with the ΔSPI1-5 mutant, had a significantly higher ability to colonise the spleen of infected chicken, and also by the ΔSPI1&2 selleck mutant which did not differ in colonisation of liver and spleen from the ΔSPI1-5 mutant. Interestingly, the deletion of SPI-1 resulted in a significant difference from the wild type strain liver colonisation on day 5 but not on day 12 in agreement with the results of Desin et al. [19] suggesting that decreased liver colonisation by the ΔSPI1

mutant might be caused by its slower translocation through the gut epithelium. On the other hand, the ΔSPI2 mutant showed decreased liver colonisation both on day 5 and day 12 when compared with the wild-type strain, which is consistent with the role of SPI-2 encoded proteins in intra-macrophage survival [10]. The importance of SPI-1 and SPI-2 was further confirmed by the virulence of SPI1o and SPI2o mutants because the presence of each of these pathogeniCity islands individually increased the virulence of S. Enteritidis Lenvatinib for chickens. SNX-5422 datasheet Our observations on SPI-1 and SPI-2 as the most important SPIs are similar to those of Dieye et al. except for the fact that we could not confirm that

SPI-1 would be more important than SPI-2 for Salmonella infection of chickens [17] although we did observe that SPI-1 was the most important for the induction of inflammation as supported by the cytokine inductions and the influx of heterophils. Interestingly, unlike the bovine and murine models [23, 24], we did not observe any correlation between the absence of SPI-2 and the induction of proinflammatory or any other cytokines in the avian caeca. Furthermore, we did not observe any effect of SPI-3, SPI-4 and SPI-5 deletions on the virulence of S. Enteritidis for chickens. This agrees with the observations of Morgan et al. who showed that SPI-4 genes were superfluous and SPI-3 genes and the pipB gene of SPI-5 played only a minor role in the colonisation of the chicken gut by S. Typhimurium [13]. However since the SPI1&2o mutant showed reduced ability to colonise the spleen 4 days post infection when compared with the wild-type S. Enteritidis infection, this shows that SPI-3, SPI-4 and SPI-5 collectively influenced the virulence of S. Enteritidis for chickens although these 3 SPIs individually did not contribute to the ability of S.

We isolated a single protein, IsaB Subsequently, we found that I

We isolated a single protein, IsaB. Subsequently, we found that IsaB did not play a role in regulation of ica expression, was not localized to the cytoplasm where it could potentially play a regulatory role but

rather was secreted and MG-132 in vivo partially associated with the bacterial cell surface, and bound to RNA, ssDNA, and dsDNA with no apparent sequence specificity. Because a number of studies have shown a role for extracellular DNA in biofilm formation, we hypothesized that VX-770 research buy the extracellular DNA-binding protein IsaB could play a role in this process [18–21]. However, we found that IsaB did not contribute to biofilm formation under a variety of conditions. This study is the first to assign a function to the putative virulence factor IsaB. The physiologic role of binding extracellular nucleic acids is still unclear. Results Isolation of IsaB by RNA Affinity Chromatography We hypothesized that an RNA-binding protein could regulate ica expression at the post-transcriptional level through binding to the 5′-untranslated region (5′-UTR). To isolate factors that bound to the 5′-UTR, we designed an RNA Affinity Chromatography assay using a biotinylated chimeric oligonucleotide (WTUTR-c) based on the sequence upstream www.selleckchem.com/products/PD-0332991.html from the ica locus as shown in Table 1. The 3-nt at the very beginning and end were

synthesized as deoxyribonucleotides to protect the oligo from exoribonuleases, and the remaining 40-nt were ribonucleotides. The chimeric

oligo was immobilized on streptavidin-coated magnetic particles, which were used to isolate proteins from whole cell lysates of S. aureus strain MN8. A single 19.5 kDa protein was detectable by Coomassie staining (data not shown), and was identified by Mass Spectral analysis as the immunodominant surface antigen B (IsaB). Table 1 Oligonucleotides used in this study are shown Oligo name Sequence WTUTR-c 5′-BIOTIN-TGCaauuacaaauauuuccguuuaauuauaacaacaaucuauuGCA-3′       IsaBIntein 5′-GGGCATATGAATAAAACCAGTAAAGTTTGTGTAGC-3′         IsaBInteinREV 5′-GGTTGCTCTTCCGCAACCTTTACTTGTTTTGTATGGTGTATGTCC-3′ isaBDELFWD 5′-GGATCCCGGATTTAGGCAATTCTTTTAATGC-3′              isaBDELREV 5′-GGATCCCATTAGAACTAATGTGCTTTGATGG-3′             isaBXhoFWD 5′-GGGCATATGGTTTGTGTAGCAGCAACATTAGC-3′            isaBXhoREV 5′-GGGCTCGAGCGAAGTAACAGTTGGACATACACC-3′           icaUTR6 5′-GUUUAAUUAUAACAACAAUCUAUUGCA-3′                BioticaPRO 5′-BIOTIN-ATTGVGTTATCAATAATCTTA-3′               IcaRcloneFWD 5′-GGTGGGATCCTTGAAGGATAAGATTA-3′            WTUTR(RNA) 5′-Biot-tegugcaauuacaaauauuuccguuuaauuauaacaacaaucuauuGCA-3′        Deoxyribonucleotides are shown in capital letters and ribonucleotides are shown in lower case.

A recombination event involving the duplicate genes encoding for

A recombination event involving the duplicate genes encoding for the OMPs HopM and HopN, during human infection, which generated

new alleles of these OMPs [21] is added proof. Conclusion The results obtained in the present study suggest that homB and homA genes may be among the H. pylori OMP coding genes contributing to the mechanisms of H. pylori persistence, and would therefore be implicated in the development of disease. Methods Bacterial strains A total of 455 H. pylori strains isolated from patients with upper gastrointestinal symptoms, from 10 different countries were included in the analysis. Table 4 summarizes the characteristics of the study population. Three H. pylori reference strains were used: 26695 strain (ATCC 700392), carrying one copy of homA gene (HP0710); HPAG1 strain, carrying one copy of homB gene (HPAG1_0695) and J99 strain (ATCC 700824), carrying one copy of each gene, Mocetinostat homA (jhp0649) and homB (jhp0870) [12–14]. Table 4 Distribution of Helicobacter pylori strains included in the study (n = 455), according to the geographical origin, gender and patient’s

age. Origin No. of strains Gender, % male Median age ± SD (years) Western countries Portugal 115 47.3 51.8 ± 15.4 France 35 82.9 47.7 ± 14.1 Sweden 27 58.8 66.6 ± 11.2 Germany 20 50.0 58.6 this website ± 11.9 USA 29 67.9 48.7 ± 12.0 Brazil 56 52.4 52.8 ± 16.4 Colombia 19 57.9 50.0 ± 12.7 East Asian countries Japan 72 57.9 44.3 ± 12.7 South Korea 71 76.1 44.7 ± 9.9 African country Burkina Faso 11 N.A. N.A. No., number SD, standard deviation N.A. not available H. pylori strains were cultured from gastric biopsies on agar supplemented with 10% horse blood, preserved in Trypticase Rolziracetam soy broth supplemented with 20% Glycerol and maintained at -80°C until used. Genomic DNA was extracted from a 48 h culture, using the QIAamp DNA mini kit (Qiagen GmbH, Hilden,

Germany), according to the manufacturer’s instructions. Genotyping of homB and homA by PCR and sequencing A single PCR assay was used to discriminate between the homB and homA genes (fragments of 161 bp and 128 bp, respectively) [8]. In order to study the diversity of homB and homA genes, PCR primers find more targeting a conserved region of the flanking genes of both loci jhp0649 and jhp0870, according to the numbering of the J99 strain [13], were designed for amplification of the entire genes [8]. The fragments were subsequently sequenced using the PCR primers and internal primers, as previously described [8]. Sequence analysis and phylogeny Similarity plots, using SimPlot Version 3.5.1 http://​sray.​med.​som.​jhmi.​edu/​SCRoftware, were based on multiple alignments of the full nucleotide sequences of homB and homA genes generated by the BioEdit Sequence Alignment Editor (Version 7.0.1) [35]. Nucleotide sequences were translated using Translate Nucleic Acid Sequences software [36]http://​biotools.​umassmed.​edu/​cgi-bin/​biobin/​transeq.

Biodivers Conserv 17:623–641CrossRef Møller AP, Flensted-Jensen E

Biodivers Conserv 17:623–641CrossRef Møller AP, Flensted-Jensen E, Mardal W (2006) Dispersal and climate change: a case

study of the Arctic tern Sterna paradisaea. Glob Change Biol 12:2005–2013CrossRef Morales JM, Ellner SP (2002) Scaling up animal movements in heterogeneous landscapes: The importance of behavior. Ecology 83:2240–selleck kinase inhibitor 2247CrossRef Nathan R, Getz WM, Revilla E, Holyoak M, Kadmon R, Saltz D, Smouse PE (2008) A movement Dibutyryl-cAMP ecology paradigm for unifying organismal movement research. Proc Natl Acad Sci USA 105:19052–19059CrossRefPubMed Noordijk J, Sýkora KV, Schaffers AP (2008) The conservation value of sandy highway verges for arthropods—implications for management. Proc Neth Entomol Soc Meet 19:75–93 Opdam P, Wascher D (2004) Climate change meets habitat fragmentation: linking landscape and biogeographical scale levels in research and conservation. Biol Conserv 117:285–297CrossRef Parmesan C, Yohe G (2003) A globally coherent fingerprint of climate change impacts across natural systems. Nature 421:37–42CrossRefPubMed Root RB, Kareiva PM (1984) The search for resources by cabbage butterflies (Pieris rapae)—ecological consequences and adaptive significance of markovian movements in a patchy environment. Ecology 65:147–165CrossRef Root TL, Price JT, Hall KR, Schneider SH, Rosenzweig C, Pounds JA (2003) Fingerprints of global

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Conclusion In this study we show that siderophore-mediated iron u

Conclusion In this study we show that siderophore-mediated iron uptake is important for the virulence of P. luminescens to insect larvae. This is similar to what has been reported for other pathogens and further highlights the relevance of Photorhabdus as a model for studying bacteria-host interactions [43]. Moreover, in contrast to what we previously reported in another species of Photorhabdus (P. temperata K122) [11], we show that siderophore-mediated

this website iron uptake in P. luminescens TT01 is not 4SC-202 chemical structure required for the growth and development of the nematode. Therefore it appears that different Photorhabdus-Heterorhabditis complexes have specific requirements for iron. In addition we show that the yfeABCD operon (encoding the Yfe divalent cation transporter)

is required for virulence in some, but not all, insect hosts. Although the Yfe transporter can mediate the uptake of either Fe2+ or Mn2+ we have shown that this transporter is involved in iron uptake during pathogenicity. On the other hand we present data that suggests that the Yfe transporter may be involved in Mn2+-uptake during growth in the gut lumen of the IJ nematode. Therefore, the substrate specificity of the Yfe Geneticin transporter in P. luminescens TT01 appears to be dependent on the invertebrate host colonized by the bacteria. Methods Bacterial strains and growth conditions Strains used in this study are listed in Table 3. Photorhabdus temperata K122,

Photorhabdus luminescens subsp laumondii TT01 and Escherichia coli strains were routinely cultured in Luria-Bertani (LB) broth or on LB agar and were incubated at 30°C or 37°C respectively. CAS agar, for the detection of siderophores, was prepared by adding CAS solution (1:10 (v:v)) into the LB agar just before pouring. CAS solution was prepared as described previously [11]. When required antibiotics were added at the following final concentrations: kanamycin (Km) 50 μg/ml, ampicilin (Amp) 100 μg/ml, chloramphenicol (Cm) 20 μg/ml and rifampicin ID-8 (Rif) 100 μg/ml. Table 3 Bacterial strains used in this study Strain Genotype Reference Photorhabdus     P. temperata (Pt) K122 Spontaneous RifRmutant Joyce and Clarke, 2003 P. luminescens (Pl) TT01 Spontaneous RifRmutant Bennett and Clarke, 2005 BMM417 K122 exbD::Km Watson and Clarke, 2005 BMM430 TT01 ΔexbD This study BMM431 (Δyfe) TT01 ΔyfeABCD This study BMM432 (Δfeo) TT01 ΔfeoABC This study BMM433 TT01 ΔexbD Δyfe This study BMM434 TT01 ΔexbD Δfeo This study BMM435 TT01 Δfeo Δyfe This study BMM436 TT01 ΔexbD Δfeo Δyfe This study E.coli     S17-1(λpir) lysogenised with λpir, replication of ori R6K Laboratory stock Construction of deletions in exbD, feoABC and yfeABCD Targeted deletion mutants were constructed as previously described [10].