The electrochemical measurements were completed using a BAS Epsilon Electrochemical Workstation (Bioanalytical Systems, Inc., West Lafayette, IN, USA) and a custom-built Teflon cell [53] with a defined working electrode area of 0.032 cm2, a platinum wire (Alfa Aesar, Ward Hill, Navitoclax mw MA, USA) counter

electrode, and an Ag/AgCl (3 M NaCl) reference electrode (Bioanalytical Systems, Inc., West Lafayette, IN, USA). All potentials are reported with respect to the Ag/AgCl reference electrode. The electrolyte solutions were made using water that had been purified through successive reverse osmosis, deionization, and UV purification stages. All chemicals were purchased from Sigma-Aldrich (St. Louis, MO, USA) and used as received. All experiments were carried out at room temperature. The films were deposited from 0.5 M H3BO3 and 1 M Na2SO4 solutions with varying NiSO4 and CuSO4 concentrations (the sum of which was held constant at 0.11 M). The potential of the working

electrode was stepped from open circuit to -1,200 mV until a total 50 mC of charge had been deposited. The dealloying step was performed in a 1 M Na2SO4 solution using linear sweep voltammetry (LSV). The potential was swept from 0mV to between 2,100 and 2,400mV at a scan rate of 5mV/s. Characterization Characterization of the composition, structure, selleck products and reactivity of all the samples was performed before and after the dealloying step. Electrochemical capacitance measurements were carried out in a check details 1 M Na2SO4 solution using cyclic voltammetry (CV). The potential was cycled from -250 to 0 mV back to -250 mV at scan rates from 25 to 400 mV/s. The average current for the forward and reverse scans was graphed vs. the scan rate to extract the observed capacitance, a measure of the effective area of the sample. Measurement of the HER was performed in 1 M NaOH. The sample was first pretreated by the application of a constant current of 50 μA for 5 min. Then, the HER measurement was completed by sweeping

the potential from -1,400 to -1,200 mV at a scan rate of 5 mV/s. The potential vs. Ag/AgCl was converted to overpotential based on the standard electrode potential of the HER and the pH of the electrolyte [54], and the current density was calculated with respect to the geometric area of the sample [53]. The current vs. overpotential data were fit to the Tafel equation to obtain the Tafel slope and exchange current density for the measured HER [55]. SEM and EDS measurements were carried out using a TM3000 Tabletop SEM (Hitachi, Tokyo, Japan) with a Quantax 70 EDS attachment (Bruker, Madison, WI, USA). Images were taken over a variety of field view sizes from ×60 to ×30,000 magnification. Composition measurements were extracted from EDS spectra taken at ×250 magnification, and Quantax 70 software was used to extract Ni and Cu compositions from the spectra.

Environ Microbiol 2008, 10:2824–2841.PubMedCrossRef 15. Marinho MJM, Albuquerque CC, Morais MB, Souza MCG, Silva KMB: Establishment of protocol for Lippia gracilis Schauer micropropagation. Rev Bras Plantas Med 2011, 13:246–252.CrossRef 16. Blank AF, Oliveira TC, Santos RB, Niculau ES, Alves PB, Arrigoni-Blank M: Genotype – age interaction in pepper-rosmarin. In International Horticulture Congress 28, Seminar Abstracts . Lisboa; 2010:77. 17. Pitcher DG, Saunders NA, Owen RJ: Rapid extraction of bacterial genomic DNA with guanidium thiocyanate. Lett Appl Microbiol 1989, 8:151–156.CrossRef 18. Sambrook J, Fritsch EF, Maniatis T: Molecular cloning: a laboratory

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(CLSI): Methods for dilution antimicrobial susceptibility tests. 4th edition. Wayne, PA, USA: Approved Standards, M7-A4; 2008. 23. Silva ACR, Lopes PM, Azevedo MMB, Costa DCM, Alviano CS, Alviano DS: Biological activities of α-pinene and β-pinene enantiomers. Molecules 2012, 17:6305–6316.PubMedCrossRef 24. White TJ, Bruns TD, Lee S, Taylor J: Analysis of phylogenetic relationships Venetoclax mw by amplification and direct sequencing of ribosomal RNA genes. In PCR protocols: a guide to methods and applications. Edited by: Innis MA, Gelfand DH, Sninsky JJ, White TH. New York: Academic Press; 1990:315–322. 25. Gardes M, Bruns TD: ITS primers with enhanced specificity for basidiomycetes: application to the identification of mycorrhizae and rusts. Mol Ecol 1993, 2:113–118.PubMedCrossRef 26. Nübel U, Engelen B, Felske A, Snaidr J, Wieshuber A, Amann RI, Ludwig W, Backhaus H: Sequence heterogeneities of genes encoding 16S rRNAs in Paenibacillus polymyxa detected by temperature gradient gel electrophoresis. J Bacteriol 1996, 178:5636–5643.PubMed 27.

e., after

408 h), NH4 +, N2O, and NO2 – formed 83.0, 15.5, and 1.5%, respectively, of all N produced and released into the liquid media. These results substantiate the capability of An-4 to dissimilatorily reduce NO3 – to NH4 + (as main product), NO2 – and N2O (as side products) under anoxic conditions. Table 1 Turnover rates of inorganic nitrogen species by A. terreus isolate An-4 during anaerobic incubation with 15 NO 3 – enrichment (Experiment 2) Nitrogen species                           Day 0-3                           Day 3-17 NO3 selleck screening library – total −166.5 (33.9) −76.4 (13.3) NO2 – total +3.4 (0.4) +1.5 (0.3) NH4 + total +565.4 (74.8) +6.1 (12.4) N2Ototal +5.0 (0.7) +12.5 (0.9) 15NH4 + +175.4 (33.7) +11.1 CAL-101 chemical structure (6.5) 15N-N2 +0.7 (0.8) −0.4 (0.2) Rates were calculated for linear increases or decreases in the amount of the different nitrogen species during the early and late phase of anaerobic incubation. Mean rates (standard error) are given as nmol N g-1 protein h-1. Positive and negative values indicate production and consumption,

respectively. Intracellular nitrate storage The capability of An-4 to store nitrate intracellularly, a common trait of large-celled microorganisms that respire nitrate, was investigated during both aerobic and anaerobic cultivation (Exp. 3). Intracellular NO3 – concentrations (ICNO3) were high when extracellular NO3 – concentrations (ECNO3) were high and vice versa, irrespective of O2 availability (Figure  3A + B). Under oxic conditions, however, ICNO3 and ECNO3 concentrations dropped sharply within the first day of incubation (Figure  3A), whereas

under anoxic conditions, steady decreases in ICNO3 and ECNO3 concentrations were noted during 11 days of incubation (Figure  3B). In the 15N-labeling experiment (Exp. 2), the total amount of N produced in each incubation vial (185.4 ± 29.3 nmol) exceeded the total amount of NO3 – consumed (114.4 ± 27.3 nmol), implying that also 71.0 nmol ICNO3 was consumed during the anoxic incubation. The initial amount of ICNO3 transferred into the incubation vials together with the An-4 mycelia of 77.5 ± 28.9 nmol equaled the calculated amount of ICNO3 needed to close the N budget. Production of biomass and cellular energy The production of biomass Ixazomib datasheet and cellular energy by An-4 was studied during aerobic and anaerobic cultivation in the presence or absence of NO3 – (Experiment 4); biomass production was also recorded in Experiment 1. For this purpose, the time courses of protein and ATP contents of An-4 mycelia and of NO3 – and NH4 + concentrations in the liquid media were followed. Biomass production by An-4 was significantly higher when O2 and/or NO3 – were available in the liquid media (Table  2). The biomass-specific ATP contents of An-4 reached higher values when NO3 – was available in the liquid media and were invariably low in its absence (Figure  4B).

Biochemistry 33:10837–10841. doi:10.​1021/​bi00201a034 PubMedCrossRef Barzda V, Istokovics A, Sidimidjiev I, Garab G (1996) Structural flexibility of chiral macroaggregates of light-harvesting chlorophyll a/b pigment-protein

complexes. Light-induced reversible structural changes associated with energy dissipation. Biochemistry 35:8981–8985. doi:10.​1021/​bi960114g PubMedCrossRef Boxer SG (1996) Stark spectroscopy of photosynthetic systems. In: Amesz J, Hoff AJ (eds) Biophysical techniques in photosynthesis, advances in photosynthesis, vol 3. Kluwer (Springer), Dordrecht, pp 177–189 Breton J, Verméglio A (1982) Orientation of photosynthetic pigments in vivo. In: Govindjee (ed) Photosynthesis. Academic Press, New York, pp 153–193 Brixner T, Stenger J, Vaswani HM, Cho M, Selleckchem PF01367338 Blankenship RE, Fleming GR (2005) Two-dimensional spectroscopy of electronic couplings in photosynthesis. Nature 434:625–628. doi:10.​1038/​nature03429 PubMedCrossRef Büchel C (2003) Fucoxanthin-chlorophyll proteins in diatoms: 18 and 19 kDa subunits assemble into different oligomeric states. Biochemistry 42:13027–13034.

doi:10.​1021/​bi0349468 PubMedCrossRef Büchel C, Garab G (1997) Organization of the pigment molecules in the chlorophyll a/c light-harvesting complex of Pleurochloris meiringensis (Xanthophyceae). Characterization with circular dichroism and absorbance spectroscopy. J Photochem Photobiol B 37:118–124. doi:10.​1016/​S1011-1344(96)07337-X CrossRef Büchel C, Garab G (1998) check details Molecular

organisation of the chlorophyll a/c light-harvesting complex of Pleurochloris meiringensis (Xanthophyceae). Pigment binding and secondary structure of the protein. J Photochem Photobiol B 42:191–194. doi:10.​1016/​S1011-1344(98)00069-4 CrossRef Caffarri S, Croce R, Cattivelli L, Bassi R (2004) A look within LHCII: differential analysis of the Lhcb1-3 complexes building the major trimeric antenna complex of higher-plant second photosynthesis. Biochemistry 43:9467–9476. doi:10.​1021/​bi036265i PubMedCrossRef Clayton RK (1980) Photosynthesis. Physical mechanisms and chemical patterns. Cambridge University Press, Cambridge Croce R, Remelli R, Varotto C, Breton J, Bassi R (1999) The neoxanthin binding site of the major light harvesting complex (LHCII) from higher plants. FEBS Lett 456:1–6. doi:10.​1016/​S0014-5793(99)00907-2 PubMedCrossRef Croce R, Morosinotto T, Ihalainen JA, Choinicka A, Breton J, Dekker JP, van Grondelle R, Bassi R (2004) Origin of the 701-nm fluorescence emission of the Lhca2 subunit of higher plant photosystem I. J Biol Chem 279:48543–48549. doi:10.​1074/​jbc.​M408908200 PubMedCrossRef Dekker JP, Boekema EJ (2005) Supramolecular organization of thylakoid membrane proteins in green plants. Biochim Biophys Acta 1707:12–39 DeVoe H (1965) Optical properties of molecular aggregates. II. Classical theory of the refraction, absorption, and optical activity of solutions and crystals. J Chem Phys 43:3199–3208. doi:10.​1063/​1.

Growth kinetics of CFNX101 and CFNX107 were identical (data not shown), however, when pDOP-C was introduced into CFNX1017 growth of the bacterium was inhibited. The growth rate and yield diminution observed in strain CFNX107/pDOP-C relative to CFNX107 is not likely caused by the metabolic burden imposed by pDOP-C replication. The size of the parental plasmid (p42d) is approximately 374 Kb, while the size of pDOP-C is approximately 5.57 Kb; even if we take into consideration the 6-fold increase in plasmid copy-number, the amount of DNA required for replication

in CFNX107/pDOP-C is several fold lower than the amount of DNA required for replication in CFNX101. Based on these observations it can be hypothesized that RepC, being Venetoclax concentration an initiator protein, must perform three tasks: PD-1/PD-L1 inhibitor drugs recognize the origin of replication, unwind the DNA at the origin, and recruit the replisome. An excess of RepC could lead to the formation of more of replication “”bubbles”". However, if one or more elements of the replisome are suboptimal in the growing cell, then, some replication forks will be stalled

resulting in inhibition of cell division and growth. We demonstrated that pDOP-C was capable of autonomous replication in an R. etli strain lacking the parental plasmid (p42d). However, we could not introduce this construct into an R. etli strain harboring the parental plasmid. In contrast, a similar construct that contained the repC gene of S. meliloti pSymA replicated autonomously with the same behavior in both strains. This result indicates that RepC is an incompatibility factor that prevents the coexistence of p42d and pDOP-C and that the incompatibility

phenomenon is replicon-specific. Unoprostone Additionally, a construct (pDOP-C1-1086) expressing a chimeric protein consisting of the amino-terminal region of p42 RepC and 39 aa residues of the carboxy-terminal region of the pSymA RepC protein was capable of replicating as an independent entity with the same efficiency in R. etli strains, with or without p42d. This result indicates that the last 39 aa residues of the RepC carboxy-terminal region are directly involved in the incompatibility phenotype. A close inspection of this region in the RepC proteins of pSymA and p42d shows that they share 62.5% of identity, indicating that 15 amino acid residues or less are critical in promoting the incompatibility phenotype. Interestingly, however, in spite of the variations in 15 aa residues, RepC proteins of p42d and pSymA have a similar secondary structure: both possess two alpha helices of ten amino acid residues each, separated by a coiled region of six amino acid residues, in the same relative positions.

SAD, PB and WK performed cluster analysis and checked the dataset for errors. KN, PB, SAD and HN designed the Brucella specific Micronaut™ microtiter plate. SAD wrote the report. KN, HN and WK helped to draft the manuscript. All authors read, commented and approved the final article.”
“Background Mycobacterium avium subsp. paratuberculosis (MAP), the causative agent of Johne’s disease (JD) of ruminants, often BMS-777607 requires eight to sixteen weeks to see colonies in culture – a major hurdle in the diagnosis and therefore in implementation of optimal control measures. Unlike other mycobacteria, which mobilize iron via mycobactins, MAP is unable to produce

detectable mycobactin in vitro or in vivo [1–3]. Although the reasons for the in vitro mycobactin dependency of MAP are currently unknown, we AZD1208 have recently shown that the mycobactin (mbt) operon promoter is active and that the mycobactin genes are transcribed by MAP inside macrophages [4] and in tissues of naturally infected animals (accepted for publication in BMC Genomics). Pathogenic mycobacteria encounter a wide variety of stressors inside the host cells and their ability to overcome iron deprivation and iron toxicity represents a major virulence determinant [5]. Transcript and protein profiling of MTB and other pathogens in response

to in vitro iron stress is well documented [6–9]. While MAP transcriptome or proteome profiles in response to heat shock, pH, oxidative stress, hypoxia, and nutrient starvation have been demonstrated [10–12], stress responses to iron supplementation or starvation are lacking. Iron dependent regulator (IdeR) has been very well studied as a global regulator involved in maintaining iron homeostasis in Mycobacterium tuberculosis (MTB) [13]. Recently we have demonstrated that IdeR of MAP in the presence of iron recognizes a consensus sequence on the promoter called “”iron box”" and regulates expression of genes involved in iron acquisition (mbt) and storage (bfrA). Liothyronine Sodium More interestingly, we demonstrated

that polymorphisms in the promoter of iron storage gene (bfrA) in S MAP strains relative to C MAP strains results in a differential gene regulation [4]. IdeR dependent repression of bfrA in the presence of iron suggests variations in iron storage mechanisms and/or iron requirements in cattle and sheep MAP strains. Comparative genomic hybridizations, short sequence repeat analysis and single nucleotide polymorphisms of MAP isolates obtained from diverse host species have established and indexed genomic differences between C and S strains of MAP [14–19]. Phylogenetic analysis of sequences has identified C and S strains as separate pathogenic clones that share a common ancestor [20–23]. Furthermore, cellular infection studies show distinctive phenotypes between the two MAP strain types [24, 25].

Among these we found genes encoding repair proteins like FANC family members and BRCA1. 103 genes were upregulated such as genes encoding PDGFRB, ECM components and adhesion proteins. Further analysis will reveal whether this signature may have prognostic value and if CAFs can be modulated by Dasatinib to be less supportive to tumor cells. In conclusion, we identified several small molecule inhibitors with significant effects on CAFs. Our study may guide the development of novel treatment strategies combining these inhibitors with conventional chemotherapy. O187 Monitoring Tumour Response to the Anti-angiogenic Therapy Sunitinib with an F18-labeled Angiogenesis Imaging Agent Lucy Allen 1 , Mark Battle1, selleck kinase inhibitor Luisa

Contreras1, Joanne Cooper1, Rochelle Lear1, Julian Goggi1, Clare Durrant1 1 Medical Diagnostics, GE Healthcare, Amersham, Buckinghamshire, UK Introduction : The RGD-binding integrins αvβ3 and αvβ5 play key roles in tumour angiogenesis.

We examined an [18F] labeled small peptide (AH111585) containing an RGD (Arg-Gly-Asp) sequence. AH111585 binds with high affinity (nM) to αvβ3 and αvβ5 integrins, which are highly expressed on tumour neovasculature. In this study, [18F]AH111585 was used to examine the response of human glioblastoma (U87) xenografts to treatment with the anti-angiogenic EPZ-6438 solubility dmso therapy Sunitinib. Materials & methods: U87 tumour uptake of [18F]AH111585 was determined by microPET imaging (% id/g) Y-27632 2HCl following administration of the anti-angiogenic therapy, such as Sunitinib. Tumour microvessel density (MVD) was also analysed post-therapy. Results

: Dymanic mircoPET imaging of [18F]AH111585 uptake demonstrated that tumour uptake peaked ~30 mins post-injection of the tracer (5% id/g). Whole body biodistribution studies confirmed rapid clearance of [18F]AH111585 from the blood with predominantly urinary excretion. Following administration of the clinically relevant anti-angiogenic therapy Sunitinib, a reduction in [18F]AH111585 tumour uptake was demonstrated compared to vehicle controls. Skeletal muscle, used as a reference tissue, demonstrated equivalent [18F]AH111585 uptake pre- and post-therapy. A reduction in MVD was also seen in anti-angiogenic therapy treated tumours. Conclusions : The data demonstrate that [18F]AH111585 can detect changes in tumour uptake following acute anti-angiogenic therapy. The results suggest this imaging agent may provide clinically important information to guide patient management and monitor response to anti-angiogenic therapies. Poster No. 1 Mesenchymal Stromal Cells (MSC) in AML Bone Marrows Carry Clonal Genomic Abnormalities Michael Andreeff 1 , Teresa McQueen1, Marina Konopleva1, Christopher Williams2, Vicki Hopwood3, Taylor Appleberry2, Corinn Rich2, Steven Kornblau1, Rui-Yu Wang1 1 Molecular Hematology & Therapy, Department of Stem Cell Transplantation and Cellular Therapy, UT M. D. Anderson Cancer Center, Houston, TX, USA, 2 PerkinElmer, Inc.

Similar to Karlsson, our lab has observed increased rpS6 phosphorylation 45 minutes after cycling exercise after both placebo and carbohydrate-protein beverages, although rpS6 phosphorylation was significantly higher after carbohydrate-protein compared to the placebo beverage [47]. Our lab has also observed timing of rpS6 phosphorylation in rats that was highly correlated to insulin [15]. rpS6 phosphorylation was higher 30 minutes post exercise in MK-1775 chemical structure animals given carbohydrate-protein post exercise compared to

fasted, exercised controls. Interestingly, rpS6 phosphorylation was significantly increased at 90 minutes in animals that did not receive supplementation. At both time points, insulin was elevated in the respective animal groups compared to exercised controls. In the current study, we would expect the higher insulin and mTOR phosphorylation at 60 minutes after Cereal to

result in higher rpS6 phosphorylation compared to Drink, but that did not occur, possibly due to the amount of supplementation provided or biopsy timing. The nearly identical increase in rpS6 phosphorylation for both Cereal and Drink suggest that these changes were due to exercise and independent of supplementation. https://www.selleckchem.com/products/voxtalisib-xl765-sar245409.html For translation initiation to occur, mTOR must increase phosphorylation of eukaryotic translation initiation factor 4E (eIF4E) binding protein 1 (4E-BP1), releasing eIF4E to bind to eIF4G, forming the eIF4F complex. Phosphorylation of eIF4E may be affected by phosphorylation of MAP kinase interacting serine/threonine kinase 1 and 2 (MNK1/MNK2) [52]. Ueda et al. [52] established that changes in p38 MAPK phosphorylation of MNK1 directly influenced the levels of eIF4E phosphorylation while ERK1/2 activates both MNK1 and MNK2, but primarily affects the basal level of pentoxifylline eIF4E phosphorylation. The role of phosphorylated eIF4E in protein synthesis is unclear; while some studies have concluded that

phosphorylation of eIF4E is necessary for translation [53] others have not [52, 54, 55]. We observed a slight, insignificant decrease in phosphorylation of eIF4E after both Drink and Cereal, with no difference between treatments (Figure 6). This lack of change in phosphorylation of eIF4E between treatments agrees with the findings of Gautsch et al. [31], who observed no change in post-exercised rats that consumed saline, carbohydrate or a mixed meal. In addition, there was no difference in phosphorylation of eIF4E between fasted-rested rats and all exercise groups, suggesting that exercise did not affect eIF4E phosphorylation. The form of our recovery foods did not seem to affect our results, although the rate of gastric emptying would be expected to be lower for solid food versus liquid food. Reed et al.

This supports the notion that TIP60 might play an important role during Salmonella infection. This increase is SseF-independent, as similar increase was also observed when infected with an sseF mutant Salmonella strain and TIP60 was not concentrated at the vacuoles (data not shown). SseF was not detected in infected cells possibly due to the low amounts translocated during Salmonella infections. CH5424802 Figure 3 TIP60 is up regulated upon Salmonella infection. HeLa cells were infected with wild-type Salmonella for the indicated time intervals. Infected cell lysates were subjected

to SDS-PAGE followed by Western blot using anti-TIP60 antibody (upper panel). Actin levels in the same samples were also determined as a control (lower panel). TIP60 is required for efficient intracellular Salmonella replication Previous studies have shown that SseF is required for efficient intracellular

Salmonella replication in macrophages [10]. Since TIP60 acetyltransferase interacts with SseF, TIP60 might be required for efficient intracellular Salmonella replication. To test this, we used siRNA to down-regulate the endogenous level of TIP60. Macrophages were transfected with a plasmid expressing TIP60 siRNA or a control vector expressing the BVD-523 datasheet scrambled siRNA. As shown in Fig. 4, TIP60 siRNA effectively suppressed the endogenous TIP60 expression, while the control siRNA did not. Transfected macrophages were infected with wild-type S. typhimurium or the sseF mutant strains. As shown in Fig. 4, down-regulation of TIP60 leads to less efficient MycoClean Mycoplasma Removal Kit Salmonella replication comparable to the level of sseF mutant strain [10]. There was not significant replication change in cells expressing the scrambled siRNA. These data support our notion that TIP60 is required for efficient intracellular Salmonella replication in macrophages. Figure 4 TIP60 is required for efficient Salmonella replication. Transfected macrophages

were infected with wild-type S. typhimurium or the sseF mutant strains at an MOI of 10. Extracellular bacteria were removed by washing and gentamicin treatment. At 2 and 24 h after bacterial invasion, cells were lysed, and the number of intracellular bacteria was enumerated. The data shown were obtained from three independent experiments with standard errors. The effect of TIP60 knockdown is verified by Western blot using the anti-TIP60 antibodies. Actin was used a control. Discussion We do not know yet the molecular mechanism of how SseF and TIP60 interaction affects the SCV and intracellular Salmonella replication. Ideally, a mutant SseF lacking the TIP60-binding domain can be used to assess the requirement for SseF-TIP60 interaction for its function, however such a mutant is defective in secretion and thus not translocated, making it impossible to assess its effect during infection.

Presently, attenuated pathogens such as Salmonella, Shigella, Listeria, Yersinia, PLX4032 as well as, non-pathogenic Escherichia coli have been used as experimental live delivery systems [17, 18]. An advantage of using attenuated pathogens as DNA vaccine vehicles is that they possess mechanisms to adhere or invade host cells with a negligible risk of reversion to a virulent strain via gene transfer or mutation. However, a potential concern is the risk of increased virulence in young or immunocompromised individuals. The use of food-grade lactic acid bacteria

(LAB) as DNA delivery vehicle represents an alternative and attractive strategy to deliver DNA vaccines at the mucosal surfaces Daporinad ic50 (ref review by 19 and 20). The dietary group of LAB, including Lactococcus lactis

and many species of Lactobacillus, is generally regarded as safe (GRAS) organisms of which some are intestinal commensals of humans. Indeed, it has been extensively demonstrated that these bacteria are able to deliver a range of vaccine and therapeutic molecules for applications in allergic, infectious or gastrointestinal diseases [19, 21, 22]. A relatively new development, however, is their use as a vehicle for genetic immunization [23]. Previous experiments performed by our group showed that either native L. lactis (LL) or recombinant invasive LL expressing Fibronectin Binding Protein A (LL-FnBPA+) of Staphylococcus aureus or Internalin A (InlA) of Listeria monocytogenes (LL-InlA+) [24, 25], were able to deliver DNA in epithelial cells both in vitro and in vivo, demonstrating potential as gene transfer Parvulin vehicles [24–27]. However InlA does not bind to its murine receptor, E-cadherin, thus limiting the use of LL-InlA+ in in vivo murine model. On the other hand, FnBPA requires an adequate local concentration of fibronectin to bind to its receptors, integrins [28, 29]. In order to avoid the limitations of InlA and FnBPA and improve our knowledge on the key steps

by which the DNA is transferred to mammalian cells using L. lactis, LL was engineered to express a mutated form of Internalin A (mInlA; Ser192Asn and Tyr369Ser) that increased binding affinity to murine and human E-cadherin [30, 31] thus allowing for in vivo experiments in conventional mice. Herein, we describe the construction and characterization of this novel L. lactis strain as a DNA delivery vector, using cow’s milk β-lactoglobulin (BLG) allergen, to measure DNA transfer to intestinal epithelial cells (IECs) in vitro and in vivo. Overall, the production of mInLA+at the surface of Lactococcus lactis increased the invasisity of bacterium and amount of plasmid transfer by 1000 and 10 fold, respectively.