05 compared with the control media and L rhamnosus HN001) (Fig

05 compared with the control media and L. rhamnosus HN001) (Fig. 1b). Lactobacillus

plantarum DSM 2648 also had a similar effect on TEER when tested using differentiated Caco-2 monolayers (18 days old) (Fig. 1c). This study demonstrates the strain-dependent effects of lactobacilli on intestinal barrier function and that all strains of the same species should not be assumed to have similar health-promoting properties. selleck chemical Lactobacillus plantarum are effective in enhancing TEER, with three out of the five L. plantarum isolates tested having a positive effect on TEER compared with the control media. A number of human oral isolates were also effective in enhancing TEER compared with the control media. Three out of four L. rhamnosus isolates, the L. paracasei isolate and the L. oris isolate had a positive effect on TEER.

However, several of the human oral isolates had a negative effect on TEER; three out of five L. fermentum isolates and the L. jensenii isolate induced a decrease in TEER compared with the control media. In contrast, one isolate of L. fermentum induced an increase in TEER compared with the control media. Lactobacillus plantarum DSM 2648 was chosen for further investigation because it had a greater positive effect on TEER compared with the benchmark, L. rhamnosus HN001, over the 12-h test period. Acid and bile tolerance (2 and 4 h) of L. plantarum DSM 2648 was compared with that of L. rhamnosus HN001 (Fig. 2). Both bacterial U0126 price strains were able to tolerate acidic conditions (pH 4 for 4 h) without the loss of cell viability; however, both strains had a reduced viability of 6–7 log units under conditions of pH 2 for 4 h. The viability of L. rhamnosus HN001 decreased by 2 log units in the presence of 0.5% bile and by 5 log units in the presence of

Idoxuridine 1% bile, whereas the viability of L. plantarum DSM 2648 only reduced by 2 log units by 1% bile. The ability of L. plantarum DSM 2648 to adhere to intestinal cells (3 and 6 h) was also compared with that of the benchmark strain, L. rhamnosus HN001 (Fig. 3). Lactobacillus plantarum DSM 2648 adhered in higher numbers (10 times more) to both confluent undifferentiated and differentiated Caco-2 cells compared with L. rhamnosus HN001 (P<0.05 at 3 and 6 h). Lactobacillus plantarum DSM 2648 displayed better in vitro tolerance to gastrointestinal conditions compared with L. rhamnosus HN001, which has been detected in human faeces after ingestion (Tannock et al., 2000); thus, it is possible that L. plantarum DSM 2648 may also survive passage through the human gastrointestinal tract. Lactobacillus plantarum DSM 2648 was also able to prevent the deleterious EPEC-induced TEER changes observed when the EPEC strain was incubated alone (Fig. 1d); however, the action of L. plantarum DSM 2648 was transient, lasting for at most 8 h. The action of L. plantarum DSM 2648 on EPEC interactions with Caco-2 cells was further explored using coculture adherence experiments.

0) was between F oxysporum f sp melonis and F oxysporum f sp

0) was between F. oxysporum f. sp. melonis and F. oxysporum f. sp. radicis lycopersici. The sequence of ITS2 for the F. oxysporum f. sp. studied has been

obtained from NCBI and aligned. The alignment between F. oxysporum formae speciales is depicted (Supporting information, Fig. S1). The sequences of the F. oxysporum formae speciales cancer metabolism inhibitor used in this study possess variations capable of producing differences in the HRM curves. Specifically, we observed point mutations for most of the species while F. oxysporum f. sp. phaseoli was the most diverse, having on top of SNPs insertions and deletions responsible for the differences in the observed melting curves between the different formae speciales amplicons (Fig. S1). The ITS region of rRNA genes is a useful marker for discriminating species because it contains stretches of high sequence conservation, while at the same time, the size of the sequence varies in different Fusarium formae speciales (Suga et al., 2000; Visentin et al., 2010). It has been successfully used before for the identification of Aspergillus (Henry et al., 2000) and Fusarium (Gurjar et al., 2009) species. It has been previously reported that the ITS region is suitable for the identification of F. oxysporum formae speciales complex with high sensitivity and specificity (Alves-Santos et al., 2002; Visentin et al., 2010). Thus, several Fusarium species have been discriminated using

the ITS of the ribosomal DNA based on amplicon length (Visentin et al., 2010). Sequence variation at the ITS region of rRNA genes allowed a very clear and reproducible HRM curve

analysis differentiation Selleckchem SB203580 among all seven Fusarium formae speciales that were analyzed in the present study as depicted in Fig. 1b. Another conserved region, the TEF1, Rolziracetam was also tested but failed to generate high-quality discriminatory results (data not shown). A significant aspect of our results is that we were able to transfer and adapt the universal primers and standard PCR conditions previously designed to discriminate species by DNA sequencing to more rapid, closed-tube, melting curve assays like the HRM analysis; this was exemplified by successful genotyping of the seven F. oxysporum species tested. In conclusion, this is the first study describing the application of HRM curve analysis for differentiation of Fusarium formae speciales. Universal marker ITS was able to differentiate between the seven F. oxysporum formae speciales, following HRM curve analysis. The current study demonstrated that the real-time PCR-HRM method is a cheap, accurate, rapid close-tubed assay for the differentiation and genotyping of Fusarium oxysporum formae speciales complexes in pure cultures. Although our genotyping method shows the potential for being used to assign new unclassified strains to a f. sp., as yet that potential has not yet been fulfilled because we do not know enough about genetic variation within versus between formae speciales.

0) was between F oxysporum f sp melonis and F oxysporum f sp

0) was between F. oxysporum f. sp. melonis and F. oxysporum f. sp. radicis lycopersici. The sequence of ITS2 for the F. oxysporum f. sp. studied has been

obtained from NCBI and aligned. The alignment between F. oxysporum formae speciales is depicted (Supporting information, Fig. S1). The sequences of the F. oxysporum formae speciales check details used in this study possess variations capable of producing differences in the HRM curves. Specifically, we observed point mutations for most of the species while F. oxysporum f. sp. phaseoli was the most diverse, having on top of SNPs insertions and deletions responsible for the differences in the observed melting curves between the different formae speciales amplicons (Fig. S1). The ITS region of rRNA genes is a useful marker for discriminating species because it contains stretches of high sequence conservation, while at the same time, the size of the sequence varies in different Fusarium formae speciales (Suga et al., 2000; Visentin et al., 2010). It has been successfully used before for the identification of Aspergillus (Henry et al., 2000) and Fusarium (Gurjar et al., 2009) species. It has been previously reported that the ITS region is suitable for the identification of F. oxysporum formae speciales complex with high sensitivity and specificity (Alves-Santos et al., 2002; Visentin et al., 2010). Thus, several Fusarium species have been discriminated using

the ITS of the ribosomal DNA based on amplicon length (Visentin et al., 2010). Sequence variation at the ITS region of rRNA genes allowed a very clear and reproducible HRM curve

analysis differentiation 5-Fluoracil price among all seven Fusarium formae speciales that were analyzed in the present study as depicted in Fig. 1b. Another conserved region, the TEF1, Metalloexopeptidase was also tested but failed to generate high-quality discriminatory results (data not shown). A significant aspect of our results is that we were able to transfer and adapt the universal primers and standard PCR conditions previously designed to discriminate species by DNA sequencing to more rapid, closed-tube, melting curve assays like the HRM analysis; this was exemplified by successful genotyping of the seven F. oxysporum species tested. In conclusion, this is the first study describing the application of HRM curve analysis for differentiation of Fusarium formae speciales. Universal marker ITS was able to differentiate between the seven F. oxysporum formae speciales, following HRM curve analysis. The current study demonstrated that the real-time PCR-HRM method is a cheap, accurate, rapid close-tubed assay for the differentiation and genotyping of Fusarium oxysporum formae speciales complexes in pure cultures. Although our genotyping method shows the potential for being used to assign new unclassified strains to a f. sp., as yet that potential has not yet been fulfilled because we do not know enough about genetic variation within versus between formae speciales.

3) and introducing them into the ΔrodZ mutant and wild type The

3) and introducing them into the ΔrodZ mutant and wild type. The β-galactosidase activity of prodZ-3, prodZ-1-ΔHTH and prodZ-1-Δ(30-133) was 1.6, 1.5 and 3.4-fold higher, respectively, in the ΔrodZ mutant. In wild-type cells, however, the expression of ispG was decreased about 50% when rodZ on the plasmid was partially deleted, which might indicate that the RodZ protein is required for the coordinated synthesis of rodZ and ispG. Interestingly,

the expression of ispG from prodZ-1-ΔHTH was reduced in the rodZ mutant, although to a lesser extent compared with the wild type, indicating that the RodZ lacking the HTH domain might partially retain its function. Also, the ΔrodZ mutant carrying this plasmid grew slightly faster. Finally, in order to locate the minor promoter(s) Idasanutlin purchase observed with prodZ-2, we constructed additional lacZ fusions (Fig. 3) and examined their β-galactosidase activity (Table 3). The results showed that, indeed, a promoter(s) existed within Deforolimus price the rodZ-orf as well as in the intergenic region, both of which showed higher activity in the ΔrodZ mutant compared with the wild type, while the expression of ispE, another gene involved in isoprene synthesis and located in a different operon, was not increased, suggesting that

the effect of RodZ is specific to the expression of the rodZ-ispG operon. It seems that a balanced expression of some sorts between rodZ and ispG might be important, although we were unable to explain these results in an unequivocal manner. During the analysis described here, we often encountered inconsistent results with the ΔrodZ mutant and noticed that derivatives that were motile and grew faster emerged spontaneously within the population. By PCR analysis,

we confirmed the presence of the ΔrodZ (rodZ∷kan) mutation in those faster-growing derivatives (data not shown). Subsequently, we isolated one such pseudorevertant, termed KR0401ΔrodZ-mot+, and characterized the phenotype. The cells grew and expressed fliA and fliC at a level similar to that of Cytidine deaminase the wild type (Table 1). The cell shape was almost rod type, although more irregular and asymmetrical compared with the wild type (Fig. 1i). The cells tended to be more elongated than the wild type in contrast to the original ΔrodZ mutant. When extra copies of rodZ were introduced, some cells showed a filamentous morphology (Fig. 1j). The amount of peptidoglycan was also significantly higher than the original ΔrodZ mutant (Table 2). Furthermore, the expression of the plasmid-borne ispG measured by the fused lacZ activity was decreased as in the wild type when either the ΔHTH or the Δ(6-30-133) deletion was introduced (Fig. 3, Table 3).

0 Hz and a resolution of 512 × 512 pixels Mycobacterium smegmati

0 Hz and a resolution of 512 × 512 pixels. Mycobacterium smegmatis culture was grown for 14–16 h at 37 °C and the culture was either treated with 0.8 mM of decanol for 2 h or left untreated. Cells were harvested, washed with http://www.selleckchem.com/products/bmn-673.html phosphate-buffered saline (PBS) and treated with 4 μg mL−1 acridine orange for 15 min. Thereafter, cells were washed with PBS and treated with 4 μg mL−1 ethidium bromide. Cells were viewed under a fluorescence microscope. Each well of a six-well polysterene Petri dish of 9.6 cm2 was poured with 2 mL of Middlebrook 7H9 medium. Each well was inoculated with M. smegmatis mc2155 culture grown for 48 h (106 CFU mL−1) and

incubated at 37 °C for 4 days to allow biofilm formation. Thereafter, planktonic cells were pipetted out carefully and the adhered biofilm was stained with 4 μg mL−1 of acridine orange in PBS for 15 min and viewed under a fluorescence microscope. For crystal violet (CV) assay, 200 μL of a saturated culture of M. smegmatis was added to each well of a 96-well plate and incubated at 37 °C 48 h. Thereafter, culture broths from the wells were discarded.

Wells were washed with mQ water and to each well, 200 μL of 0.4% CV was added. CV was allowed to adsorb to the biofilm components for 15 min at room temperature. Next, each well was washed with mQ water Selleck Roxadustat to remove any unadsorbed CV from the wells. Then, 33% acetic acid was added to dissolve the CV adsorbed to the biofilm and the amount was measured by determining its absorbance in a microplate reader at 630 nm (Molecular Devices, Sunnyvale, CA). Long-chain fatty alcohols are long known to exhibit antimicrobial activity. To test the activity of long-chain fatty alcohols against mycobacteria, primarily the antimycobacterial activity of alcohols containing 5–13 carbons

in their chain were assessed by the disc diffusion method in an agar plate against M. smegmatis as described. The radius of zone of inhibition increased almost linearly with the number of carbon atoms in the chain from 1-hexanol to 1-decanol (Fig. 1a). Alkanols with more than 10 carbon atoms showed a drastic reduction in activity (Fig. 1a). In contrast, long-chain hydrocarbons starting from n-hexane to n-decane showed no inhibitory action against M. smegmatis. Alcohols with a different Hydroxychloroquine cost number of carbon molecules starting from pentanol to tridecanol show not only a wide range of molecular weight but also a variable degree of polarity. The ability to diffuse in the agar plate depends strongly on their polarity, viscosity and other physical properties, and thus can influence its antimicrobial activity in a plate assay. To overcome solubility and diffusion problems of different alcohols with the agar diffusion method the alcohols were solubilized in a universal solvent such as DMSO (70%) and subjected to determination of MIC by the BDS method. Table 1 summarizes the antimicrobial activities of long-chain fatty alcohols on M. smegmatis mc2155 and M.

There was additional evidence that community pharmacists are work

There was additional evidence that community pharmacists are working longer hours than previously, because their job demands it.[43] Pharmacists perceived their own role to be dominated by the dispensing and checking of prescriptions

and that their workload is, in general, high.[42,43,48] Pressure from inadequate breaks and a lack of staff were seen as problematic within the community sector.[42,44–46,48] Literature searches were completed thoroughly and systematically. find more Despite this, the number of studies identified, particularly those quantifying actual workload within community pharmacies was low. Many of the studies focused more on pharmacist stress and job satisfaction. The limited number of quantitative studies identified made combining findings problematic. Selleckchem STA-9090 Consequently, the nature of this review is narrative. A formal scoring system was not applied when assessing the studies as so few had been identified, thus permitting inclusion of papers that might otherwise have been

omitted. However, any obvious limitations were critically commented upon within the description of individual papers. Due to commercial sensitivity, workload-related research conducted internally by private pharmacy companies was unavailable for the review. The findings of this review may therefore be subject to publication bias. More research is needed in the community sector to determine the level of dispensing ifenprodil undertaken and availability of (trained) support staff. No research was identified which benchmarks the rates of dispensing in community pharmacies in the UK. This subject may be particularly difficult to research due to commercial sensitivity. This exercise has, however, been completed in a selection of Welsh hospital pharmacies, with dispensing rates being benchmarked at an average of 9.8 items per person per hour.[49]

Reported dispensing rates in community pharmacies in the USA ranged from 8.9 to 18.0 prescription items per pharmacist per hour.[50] Both of these settings differ from UK community pharmacy, and such results are not directly transferable between different environments; more research into this is needed. Two studies identified considered pharmacists’ perceptions of their workload as opposed to measurement of actual workload; there is evidence to suggest there may be a difference between the two.[39,43] There were no studies available that investigated in great detail how much time pharmacists spent on services other than dispensing (such as advanced services, enhanced services or increasingly complicated OTC medicine sales). Such information would prove useful to both policy makers and employers. Bond et al. allude to the average time spent per MUR (51 min).[43] This was useful but may also have changed as pharmacists have become more experienced at doing MURs. Savage gave an indication as to how much time pharmacists spent on OTC advice and prescription counselling.

There was additional evidence that community pharmacists are work

There was additional evidence that community pharmacists are working longer hours than previously, because their job demands it.[43] Pharmacists perceived their own role to be dominated by the dispensing and checking of prescriptions

and that their workload is, in general, high.[42,43,48] Pressure from inadequate breaks and a lack of staff were seen as problematic within the community sector.[42,44–46,48] Literature searches were completed thoroughly and systematically. IWR-1 mouse Despite this, the number of studies identified, particularly those quantifying actual workload within community pharmacies was low. Many of the studies focused more on pharmacist stress and job satisfaction. The limited number of quantitative studies identified made combining findings problematic. click here Consequently, the nature of this review is narrative. A formal scoring system was not applied when assessing the studies as so few had been identified, thus permitting inclusion of papers that might otherwise have been

omitted. However, any obvious limitations were critically commented upon within the description of individual papers. Due to commercial sensitivity, workload-related research conducted internally by private pharmacy companies was unavailable for the review. The findings of this review may therefore be subject to publication bias. More research is needed in the community sector to determine the level of dispensing 6-phosphogluconolactonase undertaken and availability of (trained) support staff. No research was identified which benchmarks the rates of dispensing in community pharmacies in the UK. This subject may be particularly difficult to research due to commercial sensitivity. This exercise has, however, been completed in a selection of Welsh hospital pharmacies, with dispensing rates being benchmarked at an average of 9.8 items per person per hour.[49]

Reported dispensing rates in community pharmacies in the USA ranged from 8.9 to 18.0 prescription items per pharmacist per hour.[50] Both of these settings differ from UK community pharmacy, and such results are not directly transferable between different environments; more research into this is needed. Two studies identified considered pharmacists’ perceptions of their workload as opposed to measurement of actual workload; there is evidence to suggest there may be a difference between the two.[39,43] There were no studies available that investigated in great detail how much time pharmacists spent on services other than dispensing (such as advanced services, enhanced services or increasingly complicated OTC medicine sales). Such information would prove useful to both policy makers and employers. Bond et al. allude to the average time spent per MUR (51 min).[43] This was useful but may also have changed as pharmacists have become more experienced at doing MURs. Savage gave an indication as to how much time pharmacists spent on OTC advice and prescription counselling.

We also measured the whcA mRNA levels during growth In log phase

We also measured the whcA mRNA levels during growth. In log phase cells, the amount of whcA mRNA was almost comparable to that of spiA mRNA (Fig. 2a), suggesting that the proteins are probably made at equivalent molar ratios. Park et al. (2011) postulated that the WhcA protein forms a complex with the SpiA RAD001 research buy protein and the SpiA–WhcA protein complex binds to its target promoters to repress genes when oxidative stress is absent, such as during the log growth phase. Our data clearly provide experimental evidence for this model. Park et al. (2011) also postulated that, in the stationary phase, the SpiA–WhcA protein complex is broken and the free

WhcA protein loses its ability to bind to its target promoters, leading to the expression of oxidative stress responsive genes. Our data also show coordinated transcriptional control of the spiA and whcA genes, whose expressions were diminished when the proteins were not needed (Fig. 2b). The whcA gene is known to be involved in the regulation of a series of genes including the thioredoxin reductase gene, which is a key member of the oxidative response system. As shown above, if whcA and learn more spiA genes function in repressing oxidative stress response genes, one can assume that the genes controlled by whcA should also be under the control of spiA. To test this hypothesis, we monitored the expression of genes that had previously been

shown to be under the control by whcA. As shown in Fig. 3a, ORFs NCgl0663 and NCgl2984, which are assumed to be the trx genes encoding thioredoxin reductases in C. glutamicum, were preferentially expressed in stationary phase cells. As was observed with P180-whcA cells (Choi et al., 2009), the expression of trx genes was either almost disappeared (NCgl0663) or significantly decreased (NCgl2984) in the P180-spiA cells. However, unlike the ∆whcA mutant, which showed derepressed expression of thioredoxin reductase,

partial repression of the trx gene was observed in the ∆spiA mutant strain. In our previous report, we showed that the whcA gene regulates the PtdIns(3,4)P2 expression of several genes, including NCgl0328 (NADH oxidase), NCgl1022 (cysteine desulfurase), NCgl2053 (alcohol dehydrogenase), and NCgl2971 (quinone reductase) (Choi et al., 2009). We also analyzed the expression of genes in the spiA mutant strains. As shown in Fig. 3b, the genes were almost completely repressed in the P180-spiA strain. As was observed with the trx genes, the expression of the genes was also decreased in the ∆spiA strain. It is evident from our previous data (Park et al., 2011) that the availability of the SpiA protein is important for regulating WhcA activity. To obtain a better understanding of the mechanism of WhcA regulation by SpiA, we performed several genetic and physiological analyses. As shown in Fig. 4, cells overexpressing the spiA (or whcA) gene show slow growth.

, 2006) In this strain, 44% of the total phospholipids correspon

, 2006). In this strain, 44% of the total phospholipids corresponded to phosphatidylcholine, followed by phosphatidylethanolamine, phosphatidylglycerol and cardiolipin, and it was suggested that phosphatidylcholine may be involved in the bacterial response to environmental conditions (Medeot et al., 2007).

The present work was designed to identify the genes involved in phosphatidylcholine biosynthesis as well as to isolate and mutate the homologous pmtA this website gene in SEMIA 6144 in order to elucidate the role of phosphatidylcholine in free-living bacteria and during symbiosis with peanut plants. Table 1 lists the bacterial strains and plasmids used in this work. Escherichia coli was grown on Luria–Bertani medium (Miller, 1972) at 37 °C. Sinorhizobium meliloti 1021 was grown on tryptone yeast medium (Beringer, 1974). Bradyrhizobium japonicum USDA 110spc4 and SEMIA 6144 were grown on B− medium (van Brussel et al., 1977) or on yeast extract mannitol

(YEM) medium (Somasegaran & Hoben, 1994), all at 28 °C. Antibiotics were added at the following concentrations (μg mL−1) Tyrosine Kinase Inhibitor Library research buy when required: carbenicillin 100, tetracycline 10, spectinomycin 200, kanamycin 50, gentamicin 10 for E. coli, and nalidixic acid 40, spectinomycin 100 and gentamicin 40 for SEMIA 6144. Plasmids pBBR1MCS-5, pK18mobsacB and their derivatives were mobilized from E. coli S17-1 into the receptor strain SEMIA 6144 (Simon et al., 1983). To Metformin supplier obtain cell-free protein crude extracts, cells were ruptured using a French press as described previously (Martínez-Morales et al., 2003). Pmt activity was determined according to de Rudder et al. (1997). To detect minor Pcs activities, the assay

developed originally for S. meliloti (Sohlenkamp et al., 2000) was performed according to the modifications described by Martínez-Morales et al. (2003). DNA manipulations were performed according to standard procedures (Sambrook & Russell, 2001). DNA and derived protein sequences were analysed using the NCBI blast network server (Altschul et al., 1997). Probes for pmt or pcs genes were obtained from plasmids indicated in Table 1. DNA probes were labelled with the DIG-DNA labelling kit (Roche Molecular Biochemicals, Germany). Chemiluminescent detection of the DIG label was performed using CSPD (Roche Molecular Biochemicals). To obtain a DNA fragment containing the pmtA gene, a size-selected genomic library of SEMIA 6144 was constructed. SEMIA 6144 genomic DNA was digested with HindIII, and DNA fragments with sizes of around 2.5 kb were cloned into pUC18. Clones carrying the gene of interest were selected by colony hybridization using pmtA of B. japonicum USDA 110 (Minder et al., 2001) as a probe. A positive clone (pDBM01) was selected and its insert was sequenced.

MM and CR) The authors declare no conflict of interest “

M.M and C.R). The authors declare no conflict of interest. “
“High concentrations of indole are known to be toxic to cells due to perturbations in membrane potential. Here, we report for the first time a transcriptome analysis of a soil model bacterium,

Pseudomonas putida KT2440, under indole treatment. We demonstrated that 47 genes are differentially expressed, including PI3K inhibitor 11 genes involved in the tricarboxylic acid cycle (TCA cycle) and 12 genes involved in chaperone and protease functions (hslV, hslU, htpG, grpE, dnaK, ibpA, groEL, groES, clpB, lon-1, lon-2, and hflk). Mutant analysis supported the observation that protease genes including hslU are essential for the indole resistance of Pseudomonas strains. Subsequent biochemical analyses have shown that indole increases the NADH/NAD+ ratio and decreases the adenosine triphosphate (ATP) concentration inside cells, due to membrane perturbation and higher expression of TCA cycle genes in the presence of indole. This energy reduction

leads to a reduction in cell size and an enhancement of biofilm formation in P. putida. The observed upregulation in many chaperones and proteases led us to speculate that protein folding might be inhibited by indole treatment. Interestingly, our in vitro protein-refolding assay using malate dehydrogenase with purified GroEL/GroES demonstrated that indole interferes with protein folding. Taken together, our data provide new evidence that indole causes toxicity to P. putida by inhibiting cellular energy production and protein folding. “
“Streptococcus sanguinis, learn more a normal inhabitant of the human oral cavity, is a common streptococcal species implicated in infective endocarditis. Herein, we investigated the effects of infection with S. sanguinis on foam cell formation and cell death of macrophages. Infection with S. sanguinis stimulated foam cell formation of THP-1, a human macrophage cell line. At a multiplicity of

infection >100, S. sanguinis-induced cell death Thymidine kinase of the macrophages. Viable bacterial infection was required to trigger cell death because heat-inactivated S. sanguinis did not induce cell death. The production of cytokines interleukin-1β and tumor necrosis factor-α from macrophages was also stimulated during bacterial infection. Inhibition of the production of reactive oxygen species (ROS) resulted in reduced cell death, suggesting an association of ROS with cell death. Furthermore, S. sanguinis-induced cell death appeared to be independent of activation of inflammasomes, because cleavage of procaspase-1 was not evident in infected macrophages. Streptococcus sanguinis is a member of the viridans streptococci and a primary colonizer of the human oral cavity (Kolenbrander & London, 1993; Nobbs et al., 2009).