For this reason,

the electrochemical inorganic mediators [8], able to catalyze the oxidation or reduction of hydrogen peroxide, have been preferred to HRP and have been used for the assembling of oxidase-based biosensors. This results in a decrease of the applied potential and the consequent avoidance of many electrochemical interferences. In this perspective, Prussian blue (PB), which has high electrocatalytic activity, stability, and selectivity for Seliciclib supplier H2O2 electroreduction, has been extensively studied and used for H2O2 detection [9]. Incorporating a thin PB film into the PPY/GOx/SWCNTs-PhSO3 − nanocomposite, the obtained hybrid shows synergistic augmentation of the response current for glucose detection. The effects of applied potential on the current response of the composite-modified electrode toward glucose, the electroactive interference, and the stability were optimized to obtain the maximal sensitivity. The resulting biosensor exhibits high sensitivity, long-term stability, and freedom of interference from other co-existing electroactive species. Methods Chemicals and instrumentation Single-walled carbon nanotubes (>90% C, >77% C as SWCNTs) were obtained from Aldrich (Sigma-Aldrich Corporation, St. Louis, MO, USA). Glucose oxidase (type X-S from Aspergillus niger, 250,000

μg−1) was purchased from Sigma. Pyrrole (98%, Aldrich), D-(+)-glucose (≥99.5%), ascorbic acid, uric acid, and acetaminophen were used as received (Sigma). All other chemicals were

of Fluorometholone Acetate analytical grade. Electrochemical AZD5582 concentration experiments were performed using a 128N Autolab potentiostat and a conventional three-electrode system with a platinum-modified electrode (disk-shaped with diameter of 2 mm; Metrohm Autolab B.V., Utrecht, the Netherlands) as the working electrode, a platinum wire as the counter electrode, and Hg/Hg2Cl2 (3 M KCl) as reference electrode (purchased from Metrohm). Unless otherwise stated, all experiments were carried out at room temperature in pH 7.4 phosphate buffer solution (0.1 M phosphate). Amperometric determination of glucose was carried out at different applied potentials under magnetic stirring. Single-walled carbon nanotubes check details functionalization For the functionalization of SWCNTs, we have adopted a procedure similar to that described by Price and Tour [5] with minor modifications as presented in Figure 1. Twenty-five milligrams of SWCNTs was dispersed in 50 mL deionized water using a high-shear homogenizer at 10,000 rpm for 30 min. The resulting suspension was transferred to a round-bottom flask fitted with a magnetic stirrer and condenser and 1.44 g sulfanilic acid (Fluka Chemical Corporation, St. Louis, Milwaukee, WI, USA) followed by addition of 0.52 mL tert-butyl nitrite (Aldrich). The reaction mixture was stirred at room temperature for 30 min then the temperature was increased to 80°C and maintained for 20 h.

mansoni[23]. This PCR detection protocol can also be easily adapted to identify intermediate host(s) and perform surveillance, which is important in developing effective strategies to control the transmission of eye worms in the field. Our phylogenetic analysis based on 18S rRNA sequences indicated that O. petrowi clustered closely with Streptopharagus and Spirocerca (Figure 3). It is known that

birds are a paratenic host for Spirocerca lupi infection in their life cycle between dogs and dung beetles [24]. Dung beetles are also the learn more intermediate host for Streptopharagus[25]. These observations suggest that dung beetles might be worth examining as one of the potential intermediate hosts. Indeed, the detection of O. petrowi DNA in various insects including dung beetles is currently ongoing as part of a separate project in determining the intermediate host(s) and transmission route(s), and the data will be reported upon the completion of the survey. Conclusions We have performed a small-scale genome buy BMS202 sequence survey (GSS), which not only rapidly generated a large number of molecular sequence data

for the first time for O. petrowi, but also provided a snapshot of the genome for the eye worm in quail. The survey also identified a large number of microsatellite sequences that may be employed in further genotyping and population genetics studies. Our phylogenetic reconstructions based on 18S rRNA sequences indicated that Spiruroidea was paraphyletic, while O. petrowi, Streptopharagus and Spirocerca formed a sister clade to the filarial nematodes. The obtained ITS sequence data

also permitted us to design specific primers for molecular detection of O. petrowi in fecal samples, which may also be adapted to detect this nematode in insect intermediate hosts for Selleckchem Rabusertib surveillance and developing strategies to control the transmission of eye worms from intermediate hosts to quail. We also determined that ~28% – 33% of the birds were O. petrowi positive, suggesting that eye worm was a significant parasite in at least some quail ranches in Texas. Acknowledgements Major funding for this research provided by Rolling Plains Quail Lck Research Foundation (http://​www.​quailresearch.​org) to GZ, AMF and DR. We thank Dr. Jason M. Fritzler at the Weber State University for his critical reading of the manuscript. Electronic supplementary material Additional file 1: Table S1: List of contigs with annotations and information on top blast hits. (XLSX 122 KB) Additional file 2: Table S2: Oxyspirura petrowi microsatellite sequences identified by the GSS (all perfect matches) using Phobos. (XLSX 84 KB) References 1. Pence DB: The genus Oxyspirura (nematoda: thelaziidae) from birds in Louisiana. Proc Helminth Soc Washington 1972,39(1):23–28.

However, RRAM suffers to replace mainstream conventional FLASH memory even though it exhibits good scalability and high speed operation (few ns). Many challenges need to be overcome. One of the challenges of RRAM is to improve the integration density which can also compete with conventional FLASH in market. In recent days, the flash technology approaches its scaling limit in sub-20-nm regime and as an alternative, three-dimensional (3D) stackable NAND flash is feasible by using through-silicon-vias

(TSV) method [17, 18]. To obtain the similar device density as the product 3D flash, the 3D scalable (<20 nm) RRAM is necessary in the future which is demonstrated in literature rarely [19–21]. Yu et al. [19] and Chien et al. [20] have reported

sidewall RRAM memories using HfO x and WO x materials, respectively. Kügeler et al. [21] have reported resistive switching effect in high-density 3D cross-point architecture using AlO x material. Fosbretabulin molecular weight Basically, the cross-point memory devices have been reported by several groups. However, there is no report on interconnection of 3D LGX818 purchase architecture of RRAM, which is one of the bottlenecks to reach high-density memory application. Therefore, a novel approach to form Cu pillar in the Al2O3 material has been investigated for the first time. A simple M-I-M structure can be transferred in the 3D cross-point architecture with Cu pillar for high-density, find more low-energy, and low-cost applications. By applying a positive voltage which is larger than the set voltage, the Cu pillar in an Al/Cu/Al2O3/TiN structure could be formed due to the migration of Cu ions and make contact from one stack to another stack as shown in Figure 1. The Cu migration has a similar function with conductive bridging resistive random access memory (CBRAM). The Cu pillar

diameter will be controlled through current limit of Methocarbamol series transistor (T1-5), and this transistor will be used to control also the current compliance of RRAM or CBRAM devices. To obtain 3D stack, the chemical–mechanical-polishing (CMP) will be used after Al2O3/BE (and/or Al2O3/TE) step. Due to this Cu pillar formation, the area consumed by cross-points will be lesser than that of the conventional cost-effective TSV method. It is well known that the TSV is used for 3D architecture. However, it has a high cost and still needs a larger area. To get a low-cost and high-density Cu interconnection for 3D stacks, 3D architecture with Cu pillar would be a good alternative to overcome the aforementioned TSV issue [22]. In this cross-point architecture (Figure 1), the Cu as an oxidize electrode or top electrode (TE) could be used; other inert electrodes such as tungsten (W) and titanium-nitride (TiN) or bottom electrode (BE) could be used; and Al2O3 film could be used as switching layer. The Al2O3 film as a resistive switching material is very promising for future applications [10–13].

To this end, Xac-GFP was cultured in static liquid XVM2 medium, a minimal medium that mimics the nutritional conditions found in plant tissues [21]. As previously described, biofilms are important for X. a. pv. citri virulence, and thus XVM2

medium was used to analyze bacterial biofilm formation in a plant-like environment. After one day of growth, some cells began to attach to the surface of the PVC plate wells, however, the majority of cells remained dispersed in the C646 culture medium (Figure 1). After three days of growth, cells initiated accumulation and formation of a biofilm (Figure 1), and after P505-15 mouse seven days, Xac-GFP cells formed a distinctly structured and dense biofilm consisting of large cell aggregations separated by a network of large channels (Figure 1) that ensured appropriate micronutrient and oxygen fluxes [22]. We also evaluated the population size of these biofilms and observed that at day seven of growth the biofilms reached a maximum population size of 1 x 109 cfu/ml. In a planktonic culture in XVM2 medium, a similar maximal population size is reached in early stationary NVP-BSK805 ic50 phase. Therefore, these two conditions of growth were used to identify differentially expressed proteins between the two lifestyles at their respective maximum population sizes and prior to the occurrence of noticeable

cell death. Figure 1 Confocal laser scanning microscopy analysis X. a . pv . citri in vitro biofilms. Representative photographs of laser scanning confocal analysis of GFP-expressing X. a. pv. citri cells cultured in static liquid XVM2 in 24-well PVC plates for one, three and seven days (upper panels). Serial images were taken at 0.5 μm distances (z-stack). White arrows point to cell aggregations and dotted white arrows point to network

channels. Scale bars: 30 μm. For a better visualization, the lower panels are images of biofilm channels and cell aggregates at 7 days. Two-dimensional gel electrophoretic analysis of protein expression and mass spectrometric identification MYO10 of the X. a. pv. citri biofilm proteome Since proteomics is a powerful method to obtain systems information on the physiology of bacterial cells, we aimed at analyzing and characterizing mature biofilms of X. a. pv. citri, and compare the proteome to that of planktonic X. a. pv. citri cells. Total proteins of these cultures were extracted and separated by two-dimensional gel electrophoresis (2-DE) (see “Methods” section). Protein extractions were performed from three independent biological samples, and two technical replicate gels for each cell type were compared. A total of 46 protein spots were differentially regulated (Figure 2), excised and processed for analysis by mass spectrometry.

Thus, we examined catalytic activity of various divalent metal ions for the nucleotidyl transfer reaction from ImpN and phosphoryl compounds in neutral aqueous solution as a model process of prebiotic synthesis of coenzymes and other biologically important nucleotides containing pyrophsoaphate bond. Among the divalent metal ions examined in our study, Mn2+, Mg2+ and Cd2+ are most effective catalyst for the nucleotidyl transfer reactions from ImpN and phosphoryl compounds. A number of nucleotide containing pyrophosphate bond, NAD, UDP-glucose, CDP-choline cap portion P505-15 manufacturer of mRNA, were prepared by these reactions. E-mail: sawai@chem.​gunma-u.​ac.​jp

A Possible New Method for an Abiogenic Synthesis of Pyrimidine Nucleosides and Their Acyclic Analogues Michael B. Simakov Group of Exobiology, Institute of Cytology RAS, Tikhoretsky Av., 4, St.Petersburg, 194064, Russia There are many unresolved

problems in abiogenic synthesis of nucleosides: (1) the absence of a feasible prebiotic pathway to the ribose; (2) the instability of this sugar; (3) the lack of efficient procedures for the synthesis of glycosidic bonds. Therefore alternative genetic macromolecules such as peptide Selleckchem Quisinostat nucleic acids (PNA) and some others have been proposed instead primordial RNA. We would like to propose a feasible pathway for an abiogenic synthesis of pyrimidine PNA monomers GS 1101 and other nucleoside analogues along with the

usual nucleosides. Such acetic acid derivatives as uracil-N′-acetic acid, thymidine N′-acetic acid, and cytosine N′-acetic acid are readily synthesized in the photochemical reaction Megestrol Acetate of nucleic acid bases (U, T, and C) with the simplest amino acid glycine at the action of UV-light (λ = 254 nm) in a water solution with good yields. The reaction of nucleic acid bases with such amino acid as β-alanine and β-or γ-aminobutyric acids, which are very common in meteorites, also yields a row of the base-N’-alkyl acid derivatives. Besides, α,γ-diaminobutyric acid forms an aspartate-derived nucleoside analogue which could serve as a base monomer for the first genetic material which has similarity with peptides (peptide bond between carboxylic group of one molecule and α-amino group of the other) and nucleic acids (heterocyclic bases at γ-amino groups). This type of reaction could also be used for synthesis of such acyclic nucleoside analogues as: (1) glycerol-derived acyclonucleoside [Base + H2N–CH2–CH2(OH)–CH2(OH)], this compound phosphorylated at one or both hydroxyl positions could make a backbone with phosphate bonds;   (2) acrolein-derived nucleoside analogues [Base + HOCH2CH(CH2NH2)CH2OH];   (3) common nucleosides [Base + ribosylamine] (it is an one step process of glicoside bond forming with good yields and great similarity with the processes of the de-novo pyrimidine nucleosides biosynthesis).

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of discontinuation of raloxifene or estrogen ATR inhibitor therapy on bone mineral density after 5 years of treatment in healthy postmenopausal women. Bone 30:599–603PubMedCrossRef 53. Yood RA, Emani S, Reed JI, Lewis BE, Charpentier M, Lydick E (2003) Compliance with pharmacologic therapy for osteoporosis. Osteoporos Int 14:965–968PubMedCrossRef 54. Caro JJ, Ishak KJ, Huybrechts KF, Raggio G, Naujoks C (2004) The impact of compliance with osteoporosis therapy on fracture rates in actual practice. Osteoporos Int 15:1003–1008PubMedCrossRef 55. Huybrechts KF, Ishak KJ, Caro JJ (2006) Assessment of compliance with osteoporosis NVP-BSK805 treatment and its consequences in a managed care population. Bone 38:922–928PubMedCrossRef 56. Siris ES, Harris ST, Rosen CJ et al (2006) Adherence to bisphosphonate therapy and fracture rates in osteoporotic women: relationship to vertebral and nonvertebral fractures from 2 US claims databases. Mayo Clin Proc 81:1013–1022PubMedCrossRef 57. Olszynski WP, Adachi J, Davison J, Davison KS (2010) Disintegration times of brand and generic bisphosphonates available in Canada. J Bone Miner Res 25:S125 58. Epstein S, Cryer B, Ragi S et al (2003) Disintegration/dissolution MEK inhibitor profiles of copies of Fosamax (alendronate). Curr Med Res Opin 19:781–789PubMedCrossRef 59. Dansereau

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Figure 8 shows a comparative study of the presented model and the typical I-V characteristics of other types of transistors [49, 50]. As depicted in Figure 8, the proposed model has a larger drain current than those transistors for some value of the drain-source voltages. The resultant characteristics of the presented model shown in Figure 8 are IWP-2 in close agreement with published results

[49, 50]. In Figure 8, DG geometry is assumed for the simulations instead of the SG geometry type. Figure 8 Comparison between proposed model and typical I – V characteristics of other types of transistors. (a) MOSFET with SiO2 gate insulator [50] (V GS = 0.5V), (b) TGN MOSFET with an ionic liquid gate, C ins >> C q[49] (V GS = 0.5 V), (c) TGN MOSFET with a 3-nm ZrO2 wrap around gate, C ins ~ C q[49] (V GS = 0.37 V), (d) TGN MOSFET with a 3-nm ZrO2 wrap around gate, C ins ~ C q[49] (V GS = 0.38 V). In order to have a deep quantitative understanding of experiments involving GNR FETs, the proposed model is intended to aid in find more the design of such devices. The SiO2 gate insulator is 1.5 nm thick with a relative dielectric constant K = 3.9 [50] (Figure 8a). Furthermore, the gate-to-channel capacitance C g is a serial arrangement of insulator capacitance C ins and quantum capacitance C

q (equivalent to the semiconductor capacitance in conventional MOSFETs). Figure 8b shows a comparative study of the presented model and the typical I-V characteristic of a TGN MOSFET with an ionic liquid gate. The availability of the ionic liquid gating [49] that can be modeled as a wrap-around gate of a corresponding oxide thickness of 1 nm and a dielectric constant ε r = 80 results in C ins >> C q, and MOSFETs Transmembrane Transproters inhibitor function close to the quantum capacitance limit, i.e., C g ≈ C q[49]. As depicted in Figure 8c,d, the comparison study of the proposed model with a TGN MOSFET with a 3-nm ZrO2 wrap-around gate for two different values of V GS is notable. A 3-nm ZrO2 (ε r = 25) wrap-around gate has C ins comparable to C q for solid-state

high-κ gating, and this is an intermediate regime among the MOSFET limit and C q limit. Recently, a performance comparison between the GNR SB FETs and the MOSFET-like-doped source-drain contacts has been carried out using self-consistent atomistic simulations [20, 21, 48–50, 56, 57]. The MOSFET demonstrates improved performance in terms of bigger on-current, larger on/off current ratio, larger cutoff frequency, smaller intrinsic delay, and better saturation behavior [21, 50]. Disorders such as edge roughness, lattice vacancies, and ionized impurities have an important effect on device performance and unpredictability. This is because the sensitivity to channel atomistic structure and electrostatic environment is strong [50].

78). Similarly, for the diagnosis of OA, only one K&L diagnosis selleck inhibitor differed between the first and second reading (kappa, 0.84). Results The mean age was 80.1 years in both groups (p = 0.97). There were 253 (72%) women among the cases and 80 (71%) in the control group (p = 0.83). In the case group, there were 172 patients (49%) with a trochanteric fracture and 177 (51%) with a femoral neck fracture.

When using both grading systems combined, 48/250 (19%) patients with hip fractures and 21/112 (19%) patients with hip contusions had OA at the injured side (Table 1, p = 0.92). At the non-injured side, we found that 61/349 (18%) had OA in the patients with hip fractures compared to 8/110 (7%) in the hip contusion group using both classifications combined (Table 1, p = 0.01). The same pattern was found using K&L grading and MJS, separately (Table 1). In a subgroup ABT-888 purchase analysis comparing the two fracture types, there was 14/96 (15%) with OA in the femoral neck group and 34/154 (22%) in the trochanteric group (Table 2, p = 0.14). Similar results were found on the non-injured side (Table 2).

We also compared each fracture separately with the controls for the presence of OA and found on the injured side that there was no difference between cases and controls. Overall, OA for femoral neck fractures was 14/96 (15%) and for controls 21/112 (19%). This gave a relative risk of OA of 0.78 (95% CI, 0.42 to 1.44, p = 0.42) for the fracture group compared with the control group. Comparing the trochanteric fractures with a rate of OA of 34/154 (22%) to the controls (19%) gave a relative risk (RR) of OA of 1.18 (95% CI, 0.72 to 1.92, p = 0.51). For the non-injured side for the cases with femoral neck fractures, the rate of OA was

26/177 (15%) compared to 8/110 (7%) for the controls, giving a RR of OA of 2.02 (95% CI, 0.95 to 4.30, p = 0.06), and for the trochanteric Clomifene fractures the rate of OA was 35/172 (20%) giving a RR for OA of 2.80 (1.35 to 5.80, p = 0.003) compared to the controls. The mean MJS was 0.1 mm smaller in the femoral neck fracture patients than controls (95% CI, −0.34 to 0.10; p = 0.27), and for the trochanteric fracture patients, MJS was 0.3 mm narrower (95% CI, −0.05 to −0.49; p = 0.02) compared to the controls. Table 1 Osteoarthritis measured by MJS and/or K&L in the hip fracture group compared with the hip contusion group   Cases (hip fracture patients) Controls (hip contusion patients) Mean difference or RR with 95% confidence interval p MJS ≤2.5 mm ipsilateral (n, %) 31/250 (12%) 16/112 (14%) 0.87 (0.50 to 1.52) 0.62 K&L grade II or higher ipsilateral (n, %) 40/250 (16%) 20/112 (18%) 0.90 (0.55 to 1.46) 0.66 Osteoarthritisa ipsilateral (n, %) 48/250 (19%) 21/112 (19%) 1.02 (0.65 to 1.63) 0.92 MJS ipsilateral (mean, SD) 3.54 (0.99) 3.51 (1.00) 0.03 (−0.19 to 0.25) 0.79 MJS ≤2.5 mm contralateral (n, %) 42/349 (12%) 8/110 (7%) 1.66 (0.80 to 3.41) 0.

Fold changes were calculated as described previously using the 2-∆∆CT method [23] implemented in the DataAssist software version 3.0 (ABI), and significance was determined using one-way ANOVA in the R statistical package (version 2.13.2). Results and discussion Genes differentially expressed in mycelia and spherules Gene expression was assessed in a total of 12 samples derived from 4 replicate samples isolated from the following three growth phases: mycelia, day 2 spherules, and day 8 spherules. A photograph of mycelia and day 2 and

day 8 spherules grown in Converse medium is shown in Figure  1. The image shows the difference in shape and size between spherules and mycelia and the increase in spherule size between 2 and 8 days of culture. A custom oligonucleotide microarray (Nimblegen), which contained probes for all predicted ORFs of the RS strain of C. immitis was used to assess gene expression. 91% of the predicted ORFs were expressed Selleck NVP-BSK805 in either mycelia or spherules, suggesting that the annotation and the detection of hybridization were

robust. Unsupervised clustering using the expression of all genes on the microarray revealed that mycelia samples clustered distinctly from spherule samples. Furthermore, spherule samples formed two sub-clusters based on the number of days in culture. A dendrogram showing that the four replicate samples cluster together is shown in Additional file 3: Figure S1. Fungal morphologic stage was the dominant determinant of the pattern of gene expression. Figure 1 Photomicrographs FG-4592 supplier of C. immitis strain RS mycelium and spherules after 2 and 8 days of culture. Notice the large increase in size as the spherules mature. Genes that were significantly differentially expressed (p < 0.05) between the three conditions (mycelia, spherules on day 2 and 8) were identified in a supervised approach using a one-way ANOVA with appropriate corrections for multiple testing (see Methods). All the up- and downregulated genes differentially expressed between each of the three conditions

Selleck ZD1839 are detailed in Additional file 4: Table S2. A heatmap depicting expression levels in each sample for the top 100 differentially expressed genes is presented in Figure  2. The heatmap indicates there was limited variation in gene expression across the four replicates within each of the three conditions, suggesting that the data was highly reproducible. Multiple patterns of gene expression are evident comparing the three different conditions we studied. One cluster of genes was expressed to a lesser extent in the mycelia condition and a greater extent in both spherule conditions and another cluster of genes were expressed at a higher level in mycelia than in spherules. The expression of four genes (CIMG_08103, CIMG_09765, CIMG_10037, CIMG_10264) exhibiting the upregulated pattern was confirmed by RT-qPCR (see Figure  3 below).

J Nat Prod 2007, 70:1180–1187.CrossRefPubMed 78. Fukuda T, Hasegawa Y, Hagimori K, Yamaguchi Y, Masuma R, Tomoda H, Õmura S: Tensidols, new potentiators of antifungal miconazole activity, produced by Aspergillus

niger FKI-2342. J Antibiot 2006, 59:480–485.CrossRefPubMed Authors’ contributions LMS participated in design of the study, carried out the experimental work, the statistical and multivariate analysis and prepared the manuscript. RL participated in design of the study, contributed to the proteome analysis and revised the manuscript. MRA carried out the cluster analysis, participated in protein annotation and interpretation and revised the manuscript. PVN and JCF participated in design of the study and revision of the manuscript. All authors read

and approved the final manuscript.”
“Background Uptake of phosphate selleck chemical by bacteria most commonly occurs via two systems, the low-affinity, constitutively expressed Pit system, and the high-affinity, phosphate-starvation induced Pst system [1, 2]. Pit systems consist of a single membrane protein, encoded by pitA or pitB, and are energized by the proton motive force [2, 3]. Pst systems are multi-subunit ABC transporters, usually encoded by a four-gene operon, pstSCAB [1, 2]. Several bacterial species also contain additional transporters for the uptake of see more alternative phosphorus-compounds. Examples include the Ptx and Htx systems of Pseudomonas stutzeri, which transport phosphonates, phosphite and hypophosphite [4, 5], and the Phn-system for the uptake of phosphonates in E. coli and several other Gram-negative bacteria [6–8]. Mycobacteria appear unique in that they contain several copies of high-affinity systems specific for phosphate: In the pathogenic species, such as M. tuberculosis, M. bovis and M. leprae, this is due to duplication of the pst

genes [9]. For example, M. tuberculosis contains three different copies of pstS, two copies each of pstC and pstA, and one copy of pstB [10], plus a homologous gene, phoT, which has been shown to fulfill the same function as pstB in M. bovis [11]. Expression of all three copies of pstS under phosphate-limited conditions MYO10 has been shown for M. bovis BCG [9], although a recent microarray analysis of phosphate-limited M. tuberculosis only found one of the pst-operons to be upregulated [12]. The environmental species M. smegmatis possesses only a single copy of the pst-operon, but it also contains a second operon, phnDCE, which encodes another phosphate-specific high-affinity transporter [13]. Furthermore, a third, as yet unidentified, high-affinity phosphate transport system may be present in M. smegmatis, because a phnD/pstS double deletion mutant still retained phosphate uptake activity with a Km-value of around 90 μM, which is similar to the values of the Pst and Phn systems [13].