Its characteristic rose-like aroma makes phenylethanol a popular ingredient in foods, beverages and cosmetics. Microbial production of phenylethanol currently relies on whole-cell bioconversion of phenylalanine with yeasts that harbor an Ehrlich pathway for phenylalanine catabolism. Complete biosynthesis of phenylethanol from a cheap carbon source such as glucose provides an economically attractive alternative for phenylalanine bioconversion. In this study, a Synthetic Genetic Array screening was applied to identify genes involved in regulation of phenylethanol synthesis in Saccharomyces cerevisiae. The screen focused on transcriptional regulation of ARO10, which encodes the major decarboxylase involved in conversion of phenylpyruvate to phenylethanol. A deletion in ARO8, which encodes an aromatic amino acid transaminase, was found to cause a transcriptional upregulation of ARO10 during growth with ammonium sulfate as the sole nitrogen source. Physiological characterization revealed that the aro8 mutation led to substantial changes in the absolute and relative intracellular concentrations of amino acids. Moreover, deletion of ARO8 led to de novo production of phenylethanol during growth on a glucose synthetic medium with ammonium as the sole nitrogen source. The aro8 mutation also stimulated phenylethanol production when combined with other, previously documented mutations that deregulate aromatic amino acid biosynthesis in S. cerevisiae. The resulting engineered S. cerevisiae strain produced over 3 mM of phenylethanol from glucose during growth on a simple synthetic medium. The strong impact of a transaminase deletion on intracellular amino acid concentrations opens new possibilities for yeast-based production of amino acid-derived products.
Deletion of the Saccharomyces cerevisiae ARO8 gene, encoding an aromatic amino acid transaminase, enhances phenylethanol production from glucose.
No sample metadata fields
View SamplesDespite the fact that clinically relevant infectious agents such as human immunodeficiency virus enter through the intestinal mucosa, the intestinal T cell response to infection remains understudied. Listeria monocytogenes (LM) has been used as a model organism for studying T cell responses and the normal route of infection for LM and a potential route for use of LM as a vaccine are through ingestion. Nevertheless, the vast majority of LM immunological studies utilize inoculation routes other than oral. Moreover in the bacterial strains used the internalin. A protein binds human E-cadherin with high affinity but poorly binds mouse E-cadherin. This receptor-ligand pairing is required for entry of LM into intestinal epithelial cells. The oral infection studies proposed here utilize a recombinant LM that expresses an internalin A protein with high affinity for mouse E-cadherin. Thus, the physiologic route and entry point of LM is recapitulated in our studies. Our preliminary studies revealed a remarkable mucosal TCR gd T cell response to oral LM infection, whose kinetics mimic an adaptive T cell response. Most importantly, this phenotypically and functionally distinct subset of mucosal TCR gd T cells are retained long-term and undergo a recall response upon challenge. The hypothesis to be tested in this proposal is that this specialized subset of putative memory TCR gd T cells is important for protection against LM infection and also regulates the long-term protective CD8 TCR ab response. This hypothesis will be tested in the following specific aims: Aim 1. To test whether a subset of TCR gd represent bona fide mucosal memory cells. A detailed kinetic, phenotypic and functional analysis of the primary and secondary TCR gd cell response to oral LM infection will be undertaken. Aim 2. To determine the requirements for mucosal TCRgd activation in response to LM infection. Here we will test the role of dendritic cells, cosfimulation and cytokines in mounting primary and secondary TCR gd cell responses. Aim 3. To visualize the mucosal TCR gd cell response to oral LM infection. The oral infection system provides an exceptional opportunity to examine the anatomy of the mucosal TCR gd cell response.
γδ T cells exhibit multifunctional and protective memory in intestinal tissues.
Sex, Age, Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
LEADeR role of miR-205 host gene as long noncoding RNA in prostate basal cell differentiation.
Cell line
View SamplesMutations in the gene encoding the transcription factor AutoImmune REgulator (AIRE) are responsible for the Autoimmune PolyEndocrinopathy Candidiasis Ecodermal Dystrophy syndrome. AIRE directs expression of tissue restricted antigens in the thymic medulla and in lymph node stromal cells and thereby substantially contributes to induction of immunological tolerance to self-antigens. Data from experimental mouse models showed that AIRE-deficiency leads to impaired deletion of autospecific T cell precursors. However, a potential role for AIRE in the function of regulatory T cell populations, which are known to play a central role in prevention of immunopathology, has remained elusive. Regulatory T cells of CD8+CD28low phenotype efficiently control immune responses in experimental autoimmune and colitis models in mice. We here show that CD8+CD28low Treg from AIRE-deficient mice are transcriptionally and phenotypically normal, exert efficient suppression of in vitro immune responses, but completely fail to prevent experimental colitis in vivo. Our data therefore demonstrate that AIRE plays an important role in the in vivo function of a naturally occurring regulatory T cell population.
Autoimmune regulator (AIRE)-deficient CD8+CD28low regulatory T lymphocytes fail to control experimental colitis.
Treatment
View SamplesWe aimed at analyzing the transcriptome changes associated with the deletion of a portion of the Alu element from MIR205HG transcript
LEADeR role of miR-205 host gene as long noncoding RNA in prostate basal cell differentiation.
Cell line
View SamplesWe aimed at analyzing the transcriptome changes associated with MIR205HG knock-down in RWPE-1 cells
LEADeR role of miR-205 host gene as long noncoding RNA in prostate basal cell differentiation.
No sample metadata fields
View SamplesThe intestinal epithelium is continuously renewed by a pool of intestinal stem cells expressing Lgr5. We show that deletion of the key autophagy gene Atg7 affects the survival of Lgr5+ intestinal stem cells. Mechanistically, this involves defective DNA repair, oxidative stress, and altered interactions with the microbiota. This study highlights the importance of autophagy in maintaining the integrity of intestinal stem cells.
Essential role for autophagy protein ATG7 in the maintenance of intestinal stem cell integrity.
Specimen part
View SamplesDepletion of immunosuppressive tumor-associated macrophages (TAM) or reprogramming towards a pro-inflammatory activation state represent different strategies to therapeutically target this frequent myeloid population. Here we report that inhibition of colony-stimulating factor-1 receptor (CSF-1R) signaling sensitizes TAM to profound reprogramming in the presence of a CD40 agonist prior to their depletion. Despite the short-lived nature of macrophage hyperactivation, combined CSF-1R/CD40 stimulation of macrophages is sufficient to trigger a productive and durable T cell response in various mouse cancer models. The central role of macrophages in regulating T cell-dependent tumor rejections was substantiated by depletion experiments and transcriptomic analysis of ex vivo sorted TAM. Since CD40 expression on human TAM varies between different tumor types, co-expression of human CSF-1R and CD40 in colorectal adenocarcinoma and mesothelioma can serve as criteria to select these tumor types for clinical development Overall design: Female C57BL/6N mice (6-8 weeks in age, obtained from Charles River) were inoculated with 106 MC38 colorectal adenocarcinoma tumor cells subcutaneously. Tumor growth curves were monitored by caliper measurement and once tumor size reached 250 mm3 in average, groups were allocated for antibody treatment. Ten mice/group were treated with 30 mg/kg IgG1 isotype control antibody clone MOPC-21 (BioXCell), 4 mg/kg anti-CD40 rat IgG2a antibody clone FGK45 (BioXCell), 30mg/kg anti-CSF-1R antibody clone 2G2, 4 mg/kg rat IgG2a control clone 2A3 (BioXCell). For depletion experiments 4mg/kg mouse anti-CD4 antibody clone GK1.5 (Biolegend), 4mg/kg anti-NK1.1 antibody clone PK136 (BioXCell) and 4mg/kg anti-CD8a antibody clone 53-6.7 (BioXCell) were administered when tumor size reached 190mm3 in average. Antibodies were given every second day for four times. In between doses two and three of the depleting antibodies, animals were further treated with vehicle control (0,9% sodium saline), MOPC21, FGK45, 2G2 or combination of FGK45 and 2G2. The anti-CSF-1R antibody or respective IgG1 control antibody were administered weekly until tumors regressed completely or animals reached termination criteria, while the anti-CD40 antibody was only administered once at day 11 simultaneously with the anti-CSF-1R antibody. All antibodies were given intraperitoneally. All procedures were performed in accordance with the National Institutes of Health Guidelines for the Care and Use of Laboratory Animals and European Union directives and guidelines.
Rapid activation of tumor-associated macrophages boosts preexisting tumor immunity.
Specimen part, Treatment, Subject
View SamplesIn this study, we assess the effect of zoledronic acid on clearance of disseminated tumour cells (DTCs) from the bone marrow in women undergoing neoadjuvant chemotherapy for breast cancer
CXCR4 Protein Epitope Mimetic Antagonist POL5551 Disrupts Metastasis and Enhances Chemotherapy Effect in Triple-Negative Breast Cancer.
Specimen part
View SamplesHuman Natural Killer (NK) cells comprise two main subsets, CD56bright and CD56dim cells, that differ in function, phenotype and tissue localization. To further dissect the heterogeneity of CD56dim cells, we have performed transcriptome analysis and functional ex vivo characterization of human NK cell subsets according to the expression of markers related to differentiation, migration or competence. Here, we show for the first time that the ability to respond to cytokines or to activating receptors is mutually exclusive in almost all NK cells with the exception of CD56dim CD62L+ cells. Indeed, only these cells combine the ability to produce interferon (IFN)-gamma after cytokines and proliferate in vivo during viral infection with the capacity to kill and produce cytokines upon engagement of activating receptors. Therefore, CD56dim CD62L+ cells represent a unique subset of polyfunctional NK cells. Ex vivo analysis of their function, phenotype, telomere length, frequencies during ageing as well as transfer experiments of NK cell subsets into immunodeficient mice suggest that CD56dim CD62L+ cells represent an intermediate stage of NK cell maturation, which after restimulation can accomplish multiple tasks and further develop into terminally differentiated effectors.
CD62L expression identifies a unique subset of polyfunctional CD56dim NK cells.
Specimen part
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