| host adaptation is contingent upon the infection route taken by pathogens. | evolution of pathogen virulence is affected by the route of infection. also, alternate infection routes trigger different physiological responses on hosts, impinging on host adaptation and on its interaction with pathogens. yet, how route of infection may shape adaptation to pathogens has not received much attention at the experimental level. we addressed this question through the experimental evolution of an outbred drosophila melanogaster population infected by two different routes (oral and s ... | 2013 | 24086131 |
| x-ray and cryo-electron microscopy structures of monalysin pore-forming toxin reveal multimerization of the pro-form. | β-barrel pore-forming toxins (β-pft), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. monalysin has been recently identified as a β-pft that contributes to the virulence of pseudomonas entomophila against drosophila. it is secreted as a pro-protein that becomes active upon cleavage. here we report the crystal and cryo-electron microscopy stru ... | 2015 | 25847242 |
| the antimicrobial compound xantholysin defines a new group of pseudomonas cyclic lipopeptides. | the rhizosphere isolate pseudomonas putida bw11m1 produces a mixture of cyclic lipopeptide congeners, designated xantholysins. properties of the major compound xantholysin a, shared with several other pseudomonas lipopeptides, include antifungal activity and toxicity to gram-positive bacteria, a supportive role in biofilm formation, and facilitation of surface colonization through swarming. atypical is the lipopeptide's capacity to inhibit some gram-negative bacteria, including several xanthomon ... | 2013 | 23690965 |
| genetic evidence for a protective role of the peritrophic matrix against intestinal bacterial infection in drosophila melanogaster. | the peritrophic matrix (pm) forms a layer composed of chitin and glycoproteins that lines the insect intestinal lumen. this physical barrier plays a role analogous to that of mucous secretions of the vertebrate digestive tract and is thought to protect the midgut epithelium from abrasive food particles and microbes. almost nothing is known about pm functions in drosophila, and its function as an immune barrier has never been addressed by a genetic approach. here we show that the drosocrystallin ... | 2011 | 21896728 |
| monalysin, a novel ß-pore-forming toxin from the drosophila pathogen pseudomonas entomophila, contributes to host intestinal damage and lethality. | pseudomonas entomophila is an entomopathogenic bacterium that infects and kills drosophila. p. entomophila pathogenicity is linked to its ability to cause irreversible damages to the drosophila gut, preventing epithelium renewal and repair. here we report the identification of a novel pore-forming toxin (pft), monalysin, which contributes to the virulence of p. entomophila against drosophila. our data show that monalysin requires n-terminal cleavage to become fully active, forms oligomers in vit ... | 2011 | 21980286 |
| biosynthesis and characterization of poly(3-hydroxydodecanoate) by +¦-oxidation inhibited mutant of pseudomonas entomophila l48. | a medium-chain-length (mcl) polyhydroxyalkanoates (phas) producer pseudomonas entomophila l48 was investigated for microbial production of 3-hydroxydodecanote homopolymer. pseudomonas entomophila l48 was found to produce mcl pha consisting of 3-hydroxyhexanoate (3hhx), 3-hydroxyoctanoate (3ho), 3-hydroxydecanoate (3hd), and 3-hydroxydodecanoate (3hdd) from related carbon sources fatty acids. in this study, some of the genes encoding key enzymes in +¦-oxidation cycle of p. entomophila such as 3-h ... | 2011 | 21838281 |
| pseudomonas entomophila and pseudomonas mendocina: potential models for studying the bacterial type vi secretion system. | a diversity of molecular translocation mechanisms, including various secretion systems, has been elaborated in host-bacterial interactions. the newly described type vi secretion system (t6ss) appears to be involved in bacterial pathogenesis by acting as a nano-syringe, contributing in translocation of several effector-proteins into the eukaryotic host cell cytoplasm. recent evidences revealed the involvement of t6ss machinery in inter-bacterial interactions. several pseudomonas species are found ... | 2011 | 21600307 |
| egfr/ras/mapk signaling mediates adult midgut epithelial homeostasis and regeneration in drosophila. | many tissues in higher animals undergo dynamic homeostatic growth, wherein damaged or aged cells are replaced by the progeny of resident stem cells. to maintain homeostasis, stem cells must respond to tissue needs. here we show that in response to damage or stress in the intestinal (midgut) epithelium of adult drosophila, multiple egfr ligands and rhomboids (intramembrane proteases that activate some egfr ligands) are induced, leading to the activation of egfr signaling in intestinal stem cells ... | 2010 | 21167805 |
| molecular cloning and characterization of an insecticidal toxin from pseudomonas taiwanensis. | an insecticidal toxin gene, tccc, was cloned from the recently discovered novel species pseudomonas taiwanensis using degenerate pcr and genomic walking. the dna sequence of the tccc gene (2,940 bp) has an open reading frame encoding 980 amino acids with a calculated molecular weight of 107.93 kda. the amino acid sequence alignment showed the highest sequence identity (41.2%) with the insecticidal toxin from pseudomonas entomophila. to examine the insecticidal functionality of the tccc gene prod ... | 2010 | 21062004 |
| effect of osmotic stress on plant growth promoting pseudomonas spp. | in this study we isolated and screened drought tolerant pseudomonas isolates from arid and semi arid crop production systems of india. five isolates could tolerate osmotic stress up to -0.73 mpa and possessed multiple pgp properties such as p-solubilization, production of phytohormones (iaa, ga and cytokinin), siderophores, ammonia and hcn however under osmotic stress expression of pgp traits was low compared to non-stressed conditions. the strains were identified as pseudomonas entomophila, pse ... | 2010 | 20700582 |
| a secondary metabolite acting as a signalling molecule controls pseudomonas entomophila virulence. | pseudomonas entomophila is an entomopathogenic bacterium that is lethal to drosophila melanogaster within 1-2 days of ingestion of high doses. flies orally infected with p. entomophila rapidly succumb despite the induction of both local and systemic immune responses. recent studies suggest that its virulence relies on its ability to cause irreversible damages to the intestinal epithelium, in contrast to what is observed with milder pathogenic bacteria such as erwinia carotovora carotovora ecc15 ... | 2010 | 20597908 |
| iron uptake and metabolism in pseudomonads. | pseudomonads are ubiquitous gram-negative gamma proteobacteria known for their extreme versatility and adaptability. some are plant pathogens (pseudomonas syringae) which have to survive on the surface of leaves while others can colonize the rhizosphere or survive in soil (pseudomonas fluorescens, pseudomonas putida), and one species, pseudomonas entomophila, is an insect pathogen. the most investigated species, pseudomonas aeruginosa, is known to be an opportunistic pathogen able to infect plan ... | 2010 | 20352420 |
| characterization of acc deaminase gene in pseudomonas entomophila strain ps-pjh isolated from the rhizosphere soil. | the enzyme 1-aminocyclopropane-1-carboxylate (acc) deaminase cleaves the ethylene precursor acc into alpha-ketobutyrate and ammonia. the decreased level of ethylene allows the plant to be more resistant to a wide environmental stress including plant pathogens. in the present study, we characterized the acc deaminase activity of a pseudomonas entomophila strain ps-pjh isolated from the red pepper rhizosphere region of red pepper grown at jinan, korea. the isolate produced 23.8 +/- 0.4 micromol of ... | 2010 | 20082369 |
| molecular detection of the entomopathogenic bacterium pseudomonas entomophila using pcr. | to develop a specific, fast and simple molecular method useful to detect the entomopathogenic bacterium pseudomonas entomophila. | 2010 | 20025650 |
| association of hemolytic activity of pseudomonas entomophila, a versatile soil bacterium, with cyclic lipopeptide production. | pseudomonas entomophila is an entomopathogenic bacterium that is able to infect and kill drosophila melanogaster upon ingestion. its genome sequence suggests that it is a versatile soil bacterium closely related to pseudomonas putida. the gacs/gaca two-component system plays a key role in p. entomophila pathogenicity, controlling many putative virulence factors and apra, a secreted protease important to escape the fly immune response. p. entomophila secretes a strong diffusible hemolytic activit ... | 2010 | 20023108 |
| comparative analysis of the virulence of invertebrate and mammalian pathogenic bacteria in the oral insect infection model galleria mellonella. | infection of galleria mellonella by feeding a mixture of bacillus thuringiensis spores or vegetative bacteria in association with the toxin cry1c results in high levels of larval mortality. under these conditions the toxin or bacteria have minimal effects on the larva when inoculated separately. in order to evaluate whether g. mellonella can function as an oral infection model for human and entomo-bacterial pathogens, we tested strains of bacillus cereus, bacillus anthracis, enterococcus faecali ... | 2010 | 19800349 |
| cyanogenesis by the entomopathogenic bacterium pseudomonas entomophila. | to investigate whether the entomopathogenic bacterium pseudomonas entomophila can synthesize hydrogen cyanide (hcn). | 2009 | 19486283 |
| siderophore-mediated iron acquisition in the entomopathogenic bacterium pseudomonas entomophila l48 and its close relative pseudomonas putida kt2440. | pseudomonas entomophila l48 is a recently identified entomopathogenic bacterium which, upon ingestion, kills drosophila melanogaster, and is closely related to p. putida. the complete genome of this species has been sequenced and therefore a genomic, genetic and structural analysis of the siderophore-mediated iron acquisition was undertaken. p. entomophila produces two siderophores, a structurally new and unique pyoverdine and the secondary siderophore pseudomonine, already described in p. fluor ... | 2009 | 19459056 |
| generation of enteroendocrine cell diversity in midgut stem cell lineages. | the endocrine system mediates long-range peptide hormone signaling to broadcast changes in metabolic status to distant target tissues via the circulatory system. in many animals, the diffuse endocrine system of the gut is the largest endocrine tissue, with the full spectrum of endocrine cell subtypes not yet fully characterized. here, we combine molecular mapping, lineage tracing and genetic analysis in the adult fruit fly to gain new insight into the cellular and molecular mechanisms governing ... | 2015 | 25670792 |
| draft whole-genome sequence of the antibiotic-producing soil isolate pseudomonas sp. strain 250j. | bacteria of the genus pseudomonas are becoming increasing well known for their ability to produce a wide range of antimicrobial compounds. in a large-scale screening for antibiotic producers, we identified a soil isolate that uses 4-hydroxyphenylacetate as the sole carbon source, pseudomonas sp. strain 250j, which produces cyclic lipodepsipeptides of the xantholysin family during the stationary phase of growth. the closest relatives of this strain are pseudomonas mosselii, pseudomonas soli and p ... | 2015 | 25403737 |
| entomopathogenic bacteria as a source of secondary metabolites. | insects are not only the most diverse group of animals on our planet, but also a huge reservoir for unusual microorganism which are a rich source of pharmaceutically interesting natural products. this review focuses on recent advances in the understanding of secondary metabolism of bacillus thuringiensis, pseudomonas entomophila, and xenorhabdus and photorhabdus bacteria all of which are entomopathogenic. genome-sequencing projects revealed the capacity of these bacteria to produce several diffe ... | 2009 | 19345136 |
| [cloning and functional analysis of cysi gene involved in siderophores biosynthesis in pseudomonas mosselii e1]. | a siderophores-producing strain e1 was isolated from the rhizosphere of cotton. its 16s rdna is identical to that of pseudomonas mosselii sp. nov. at 100% level. the suicide plasmid prl1063a carrying tn5-1063 was introduced into e1 by triparental mating and 1000 transposon insertion mutants were subsequently screened using cas assay. one mutant deficiency in siderophores production was obtained, namely, e1-185. dna sequences flanking tn5-1063 of e1-185 was amplified by tail-pcr. according to the ... | 2007 | 18062272 |
| roles for drosophila melanogaster myosin ib in maintenance of enterocyte brush-border structure and resistance to the bacterial pathogen pseudomonas entomophila. | drosophila myosin ib (myo1b) is one of two class i myosins in the drosophila genome. in the larval and adult midgut enterocyte, myo1b is present within the microvillus (mv) of the apical brush border (bb) where it forms lateral tethers between the mv membrane and underlying actin filament core. expression of green fluorescent protein-myo1b tail domain in the larval gut showed that the tail domain is sufficient for localization of myo1b to the bb. a myo1b deletion mutation exhibited normal larval ... | 2007 | 17855510 |
| the xaxab genes encoding a new apoptotic toxin from the insect pathogen xenorhabdus nematophila are present in plant and human pathogens. | xenorhabdus nematophila, a member of the enterobacteriaceae, kills many species of insects by strongly depressing the immune system and colonizing the entire body. a peptide cytotoxin has been purified from x. nematophila broth growth, and the cytolytic effect on insect immunocytes and hemolytic effect on mammalian red blood cells of this toxin have been described (ribeiro, c., vignes, m., and brehélin, m. (2003) j. biol. chem. 278, 3030-3039). we show here that this toxin, xenorhabdus alpha-xen ... | 2007 | 17229739 |
| prevalence of local immune response against oral infection in a drosophila/pseudomonas infection model. | pathogens have developed multiple strategies that allow them to exploit host resources and resist the immune response. to study how drosophila flies deal with infectious diseases in a natural context, we investigated the interactions between drosophila and a newly identified entomopathogen, pseudomonas entomophila. flies orally infected with p. entomophila rapidly succumb despite the induction of both local and systemic immune responses, indicating that this bacterium has developed specific stra ... | 2006 | 16789834 |
| complete genome sequence of the entomopathogenic and metabolically versatile soil bacterium pseudomonas entomophila. | pseudomonas entomophila is an entomopathogenic bacterium that, upon ingestion, kills drosophila melanogaster as well as insects from different orders. the complete sequence of the 5.9-mb genome was determined and compared to the sequenced genomes of four pseudomonas species. p. entomophila possesses most of the catabolic genes of the closely related strain p. putida kt2440, revealing its metabolically versatile properties and its soil lifestyle. several features that probably contribute to its e ... | 2006 | 16699499 |
| drosophila host defense after oral infection by an entomopathogenic pseudomonas species. | drosophila has been shown to be a valuable model for the investigation of host-pathogen interactions. study of the drosophila immune response has been hampered, however, by the lack of true drosophila pathogens. in nearly all studies reported, the bacteria used were directly injected within the body cavity of the insect, bypassing the initial steps of a natural interaction. here, we report the identification of a previously uncharacterized bacterial species, pseudomonas entomophila (pe), which h ... | 2005 | 16061818 |
| the drosophila mapk p38c regulates oxidative stress and lipid homeostasis in the intestine. | the p38 mitogen-activated protein (map) kinase signaling cassette has been implicated in stress and immunity in evolutionarily diverse species. in response to a wide variety of physical, chemical and biological stresses p38 kinases phosphorylate various substrates, transcription factors of the atf family and other protein kinases, regulating cellular adaptation to stress. the drosophila genome encodes three p38 kinases named p38a, p38b and p38c. in this study, we have analyzed the role of p38c i ... | 2014 | 25254641 |
| crosslinking of a peritrophic matrix protein protects gut epithelia from bacterial exotoxins. | transglutaminase (tg) catalyzes protein-protein crosslinking, which has important and diverse roles in vertebrates and invertebrates. here we demonstrate that drosophila tg crosslinks drosocrystallin, a peritrophic matrix protein, to form a stable fiber structure on the gut peritrophic matrix. rna interference (rnai) of the tg gene was highly lethal in flies and induced apoptosis of gut epithelial cells after oral infection with pseudomonas entomophila. moreover, apra, a metalloprotease secreted ... | 2015 | 26506243 |
| genetic, molecular and physiological basis of variation in drosophila gut immunocompetence. | gut immunocompetence involves immune, stress and regenerative processes. to investigate the determinants underlying inter-individual variation in gut immunocompetence, we perform enteric infection of 140 drosophila lines with the entomopathogenic bacterium pseudomonas entomophila and observe extensive variation in survival. using genome-wide association analysis, we identify several novel immune modulators. transcriptional profiling further shows that the intestinal molecular state differs betwe ... | 2015 | 26213329 |
| infection-induced host translational blockage inhibits immune responses and epithelial renewal in the drosophila gut. | typically, immune responses control the pathogen, while repair and stress pathways limit damage caused by pathogenesis. the relative contribution of damage to the outcome of pathogenesis and the mechanistic links between the immune and repair pathways are poorly understood. here, we analyze how the entomopathogenic bacterium pseudomonas entomophila induces irreversible damage to the drosophila gut. we find that p. entomophila ingestion induces a global translational blockage that impairs both im ... | 2012 | 22817988 |
| gender- and stressor-specific microrna expression in tribolium castaneum. | micrornas (mirnas) are small non-coding rnas mediating post-transcriptional regulation of gene expression in eukaryotes. addressing their role in regulation of physiological adaptations to environmental stress in insects, we selected the red flour beetle tribolium castaneum as a model. beetles were fed with the bacterial entomopathogen pseudomonas entomophila (to mimic natural infection), injected with peptidoglycan (experimental setting of strong immune responses) or subjected to either mild he ... | 2012 | 22628099 |
| screening and characterization of proline dehydrogenase flavoenzyme producing pseudomonas entomophila. | proline dehydrogenase (prodh; 1.5.99.8) plays an important role in specific determination of plasma proline level in biosensor and diagnostic kits. the goal of this research was to isolate and characterize prodh enzyme from iranian soil microorganisms. | 2011 | 22530089 |
| taxonomic characterisation of pseudomonas strain l48 and formal proposal of pseudomonas entomophila sp. nov. | an entomopathogenic, gram-negative bacterium isolated from a female specimen of the fruit fly drosophila melanogaster was taxonomically characterised. strain l48(t) was strictly aerobic, non-fermentative, oxidase and catalase positive, rod-shaped, and motile due to a polar inserted flagellum. phylogenetic analysis of the 16s rrna gene and three other housekeeping genes placed strain l48 (t) in the pseudomonas putida phylogenetic group. dna-dna hybridisation studies together with phenotypic metab ... | 2012 | 22326814 |
| insect pathogenic bacteria in integrated pest management. | the scientific community working in the field of insect pathology is experiencing an increasing academic and industrial interest in the discovery and development of new bioinsecticides as environmentally friendly pest control tools to be integrated, in combination or rotation, with chemicals in pest management programs. in this scientific context, market data report a significant growth of the biopesticide segment. acquisition of new technologies by multinational ag-tech companies is the center ... | 2015 | 26463190 |
| synthesis of medium-chain-length polyhydroxyalkanoate homopolymers, random copolymers, and block copolymers by an engineered strain of pseudomonas entomophila. | medium-chain-length polyhydroxyalkanoates (mcl-phas), widely used in medical area, are commonly synthesized by pseudomonas spp. this study tries to use β-oxidation pathways engineered p. entomophila to achieve single source of a series of mcl-monomers for microbial production of pha homopolymers. the effort is proven successful for the first time to obtain a wide range of mcl-pha homopolymers from engineered p. entomophila lac23 grown on various fatty acids, respectively, ranging from poly(3-hyd ... | 2017 | 28128887 |
| diversity, antimicrobial and antioxidant activities of culturable bacterial endophyte communities in aloe vera. | twenty-nine culturable bacterial endophytes were isolated from surface-sterilized tissues (root, stem and leaf) of aloe vera and molecularly characterized to 13 genera: pseudomonas, bacillus, enterobacter, pantoea, chryseobacterium, sphingobacterium, aeromonas, providencia, cedecea, klebsiella, cronobacter, macrococcus and shigella. the dominant genera include bacillus (20.7%), pseudomonas (20.7%) and enterobacter (13.8%). the crude and ethyl acetate fractions of the metabolites of six isolates, ... | 2015 | 26454221 |
| tribolium castaneum defensins are primarily active against gram-positive bacteria. | the red flour beetle tribolium castaneum is a destructive insect pest of stored food and feed products, and a model organism for development, evolutionary biology and immunity. the insect innate immune system includes antimicrobial peptides (amps) with a wide spectrum of targets including viruses, bacteria, fungi and parasites. defensins are an evolutionarily-conserved class of amps and a potential new source of antimicrobial agents. in this context, we report the antimicrobial activity, phyloge ... | 2015 | 26522790 |
| evolution of drosophila resistance against different pathogens and infection routes entails no detectable maintenance costs. | pathogens exert a strong selective pressure on hosts, entailing host adaptation to infection. this adaptation often affects negatively other fitness-related traits. such trade-offs may underlie the maintenance of genetic diversity for pathogen resistance. trade-offs can be tested with experimental evolution of host populations adapting to parasites, using two approaches: (1) measuring changes in immunocompetence in relaxed-selection lines and (2) comparing life-history traits of evolved and cont ... | 2015 | 26496003 |
| novel t7-like expression systems used for halomonas. | to engineer non-model organisms, suitable genetic parts must be available. however, biological parts are often host strain sensitive. it is therefore necessary to develop genetic parts that are functional regardless of host strains. here we report several novel phage-derived expression systems used for transcriptional control in non-model bacteria. novel t7-like rna polymerase-promoter pairs were obtained by mining phage genomes, followed by in vivo characterization in non-model strains halomona ... | 2017 | 27889295 |
| production of medium-chain-length 3-hydroxyalkanoic acids by β-oxidation and phac operon deleted pseudomonas entomophila harboring thioesterase gene. | 3-hydroxyalkanoic acids (3ha) are precious precursors for synthesis of value added chemicals. according to their carbon chain lengths, 3ha can be divided into two groups: short-chain-length (scl) 3ha consisting of 3-5 carbon atoms and medium-chain-length (mcl) 3ha containing 6-14 carbon atoms. to produce mcl 3ha, a metabolic engineered pathway expressing tesb gene, a thioesterase encoding gene that has been reported to catalyze acyl-coa to free fatty acids, was constructed in pseudomonas entomop ... | 2013 | 23466419 |
| determination of the structure of the o-antigen and the lipid a from the entomopathogenic bacterium pseudomonas entomophila lipopolysaccharide along with its immunological properties. | the structure and the immunology of the lipopolysaccharide (lps) of pseudomonas entomophila, an entomopathogenic bacterium isolated from the fruit fly drosophila melanogaster, was characterized. the o-antigen portion was established and resulted to be built up of a repetitive unit constituted by four monosaccharide residues, all l configured, all deoxy at c-6 and with an acetamido function at c-2: →3)-α-l-fucnac-(1→4)-α-l-fucnac-(1→3)-α-l-fucnac-(1→3)-β-l-quinac-(1→ the structural analysis of li ... | 2015 | 25996527 |
| pseudomonas soli sp. nov., a novel producer of xantholysin congeners. | a chemoorganotrophic gram-negative bacterium was isolated by means of a diffusion sandwich system from a soil sample from the sierra nevada national park, spain. strain f-279,208(t) was oxidase and catalase positive, strictly aerobic, non-spore-forming and motile by single polar flagellum. phylogenetic analysis of the 16s rrna, gyrb, rpob and rpod genes revealed that strain f-279,208(t) belongs to the pseudomonas putida group with pseudomonas mosselii and pseudomonas entomophila as its closest r ... | 2014 | 25097020 |
| virulent bacterial infection improves aversive learning performance in drosophila melanogaster. | virulent infections are expected to impair learning ability, either as a direct consequence of stressed physiological state or as an adaptive response that minimizes diversion of energy from immune defense. this prediction has been well supported for mammals and bees. here, we report an opposite result in drosophila melanogaster. using an odor-mechanical shock conditioning paradigm, we found that intestinal infection with bacterial pathogens pseudomonas entomophila or erwinia c. carotovora impro ... | 2014 | 24863366 |
| crystallization and preliminary x-ray analysis of monalysin, a novel β-pore-forming toxin from the entomopathogen pseudomonas entomophila. | monalysin was recently described as a novel pore-forming toxin (pft) secreted by the drosophila pathogen pseudomonas entomophila. recombinant monalysin is multimeric in solution, whereas pfts are supposed to be monomeric until target membrane association. monalysin crystals were obtained by the hanging-drop vapour-diffusion method using peg 8000 as precipitant. preliminary x-ray diffraction analysis revealed that monalysin crystals belonged to the monoclinic space group c2, with unit-cell parame ... | 2013 | 23908046 |
| pseudomonas guariconensis sp. nov., isolated from rhizospheric soil. | we isolated a bacterial strain designated pcavu11(t) in the course of a study of phosphate-solubilizing bacteria occurring in rhizospheric soil of vigna unguiculata (l.) walp. in guárico state, venezuela. the 16s rrna gene sequence had 99.2 % sequence similarity with respect to the most closely related species, pseudomonas taiwanensis, and 99.1 % with respect to pseudomonas entomophila, pseudomonas plecoglossicida and pseudomonas monteilii, on the basis of which pcavu11(t) was classified as repr ... | 2013 | 23847284 |
| probiotic enterococcus mundtii isolate protects the model insect tribolium castaneum against bacillus thuringiensis. | enterococcus mundtii strains isolated from the larval feces of the mediterranean flour moth ephestia kuehniella show antimicrobial activity against a broad spectrum of gram-positive and gram-negative bacteria. the in vitro probiotic characterization of one isolate revealed a high auto-aggregation score, a hydrophilic cell surface, tolerance for low ph, no hemolytic activity, and susceptibility to all tested antibiotics. we used the red flour beetle tribolium castaneum, an established model organ ... | 2017 | 28736550 |
| regulation of acetyl-coa synthetase transcription by the crbs/r two-component system is conserved in genetically diverse environmental pathogens. | the crbs/r two-component signal transduction system is a conserved regulatory mechanism through which specific gram-negative bacteria control acetate flux into primary metabolic pathways. crbs/r governs expression of acetyl-coa synthase (acsa), an enzyme that converts acetate to acetyl-coa, a metabolite at the nexus of the cell's most important energy-harvesting and biosynthetic reactions. during infection, bacteria can utilize this system to hijack host acetate metabolism and alter the course o ... | 2017 | 28542616 |
| genetic diversity of nitrogen-fixing and plant growth promoting pseudomonas species isolated from sugarcane rhizosphere. | the study was designed to isolate and characterize pseudomonas spp. from sugarcane rhizosphere, and to evaluate their plant- growth- promoting (pgp) traits and nitrogenase activity. a biological nitrogen-fixing microbe has great potential to replace chemical fertilizers and be used as a targeted biofertilizer in a plant. a total of 100 isolates from sugarcane rhizosphere, belonging to different species, were isolated; from these, 30 isolates were selected on the basis of preliminary screening, f ... | 2017 | 28769881 |
| antimicrobial peptides extend lifespan in drosophila. | antimicrobial peptides (amps) are important defense molecules of the innate immune system. high levels of amps are induced in response to infections to fight pathogens, whereas moderate levels induced by metabolic stress are thought to shape commensal microbial communities at barrier tissues. we expressed single amps in adult flies either ubiquitously or in the gut by using the inducible geneswitch system to tightly regulate amp expression. we found that activation of single amps, including dros ... | 2017 | 28520752 |
| translocation of bacteria from the gut to the eggs triggers maternal transgenerational immune priming in tribolium castaneum. | invertebrates can be primed to enhance their protection against pathogens they have encountered before. this enhanced immunity can be passed maternally or paternally to the offspring and is known as transgenerational immune priming. we challenged larvae of the red flour beetle tribolium castaneum by feeding them on diets supplemented with escherichia coli, micrococcus luteus or pseudomonas entomophila, thus mimicking natural exposure to pathogens. the oral uptake of bacteria induced immunity-rel ... | 2015 | 26701756 |
| a simple strategy for investigating the diversity and hydrocarbon degradation abilities of cultivable bacteria from contaminated soil. | the use of indigenous bacterial strains is a valuable bioremediation strategy for cleaning the environment from hydrocarbon pollutants. the isolation and selection of hydrocarbon-degrading bacteria is therefore crucial for obtaining the most promising strains for site decontamination. two different media, a minimal medium supplemented with a mixture of polycyclic aromatic hydrocarbons and a ms medium supplemented with triphenyltetrazolium chloride, were used for the isolation of bacterial strain ... | 2013 | 23386320 |
| no apparent cost of evolved immune response in drosophila melanogaster. | maintenance and deployment of the immune system are costly and are hence predicted to trade-off with other resource-demanding traits, such as reproduction. we subjected this longstanding idea to test using laboratory experimental evolution approach. in the present study, replicate populations of drosophila melanogaster were subjected to three selection regimes-i (infection with pseudomonas entomophila), s (sham-infection with mgso4 ), and u (unhandled control). after 30 generations of selection ... | 2016 | 26932243 |
| degradation of reactive black 5 dye by a newly isolated bacterium pseudomonas entomophila bs1. | the textile and dye industries are considered as one of the major sources of environmental pollution. the present study was conducted to investigate the degradation of the azo dye reactive black 5 (rb 5) using a bacterium isolated from soil samples collected around a textile industry. the bacterial strain bs1 capable of degrading rb 5 was isolated and identified as pseudomonas entomophila on the basis of 16s rdna sequencing. the effects of different parameters on the degradation of rb 5 were stu ... | 2016 | 26911309 |
| gut physiology mediates a trade-off between adaptation to malnutrition and susceptibility to food-borne pathogens. | the animal gut plays a central role in tackling two common ecological challenges, nutrient shortage and food-borne parasites, the former by efficient digestion and nutrient absorption, the latter by acting as an immune organ and a barrier. it remains unknown whether these functions can be independently optimised by evolution, or whether they interfere with each other. we report that drosophila melanogaster populations adapted during 160 generations of experimental evolution to chronic larval mal ... | 2015 | 26249109 |
| the drosophila prosecretory transcription factor dimmed is dynamically regulated in adult enteroendocrine cells and protects against gram-negative infection. | the endocrine system employs peptide hormone signals to translate environmental changes into physiological responses. the diffuse endocrine system embedded in the gastrointestinal barrier epithelium is one of the largest and most diverse endocrine tissues. furthermore, it is the only endocrine tissue in direct physical contact with the microbial environment of the gut lumen. however, it remains unclear how this sensory epithelium responds to specific pathogenic challenges in a dynamic and regula ... | 2015 | 25999585 |
| microbial synthesis of functional homo-, random, and block polyhydroxyalkanoates by β-oxidation deleted pseudomonas entomophila. | functional polyhydroxyalkanoates (phas) allow chemical modifications to widen pha diversity, promising to increase values of these biodegradable and biocompatible polyesters. among functional phas, unsaturated pha site chains can be easily grafted to add chemical groups, and to cross-link with other pha polymer chains. however, it has been very difficult to obtain structurally controllable functional homo-, random, or block pha. for the first time, a β-oxidation deleted pseudomonas entomophila w ... | 2014 | 24830358 |
| engineering the diversity of polyesters. | many bacteria have been found to produce various polyhydroxyalkanoates (pha) biopolyesters. in many cases, it is not easy to control the structures of pha including homopolymers, random copolymers and block copolymers as well as ratios of monomers in the copolymers. it has become possible to engineer bacteria for controllable synthesis of pha with the desirable structures by creating new pha synthesis pathways. remarkably, the weakening of β-oxidation cycle in pseudomonas putida and pseudomonas ... | 2014 | 24632193 |
| the maternal transfer of bacteria can mediate trans-generational immune priming in insects. | parents invest in their offspring by preparing them for defense against pathogens and parasites that only the parents have encountered, a phenomenon known as trans-generational immune priming. we investigated the underlying mechanism using the established lepidopteran model host galleria mellonella. when larvae were fed with non-pathogenic bacteria, or the entomopathogenic species pseudomonas entomophila and serratia entomophila, the activity of lysozyme and phenoloxidase increased in the hemoly ... | 2014 | 24603099 |
| fruit flies learn to avoid odours associated with virulent infection. | while learning to avoid toxic food is common in mammals and occurs in some insects, learning to avoid cues associated with infectious pathogens has received little attention. we demonstrate that drosophila melanogaster show olfactory learning in response to infection with their virulent intestinal pathogen pseudomonas entomophila. this pathogen was not aversive to taste when added to food. nonetheless, flies exposed for 3 h to food laced with p. entomophila, and scented with an odorant, became s ... | 2014 | 24598110 |
| benzene containing polyhydroxyalkanoates homo- and copolymers synthesized by genome edited pseudomonas entomophila. | microbial synthesis of functional polymers has become increasingly important for industrial biotechnology. for the first time, it became possible to synthesize controllable composition of poly(3-hydroxyalkanoate) (p3ha) consisting of 3-hydroxydodecanoate (3hdd) and phenyl group on the side-chain when chromosome of pseudomonas entomophila was edited to weaken its β-oxidation. cultured in the presence of 5-phenylvaleric acid (pva), the edited p. entomophila produced only homopolymer poly(3-hydroxy ... | 2014 | 24369356 |
| sexual activity increases resistance against pseudomonas entomophila in male drosophila melanogaster. | maintenance and deployment cost of immunity is high, therefore, it is expected to trade-off with other high cost traits like sexual activity. previous studies with drosophila melanogaster show that male's ability to clear bacteria decreases with increase in sexual activity. we subjected this idea to test using two pathogens (pseudomonas entomophila and staphylococcus succinus) and three different populations of drosophila melanogaster. | 2013 | 24010544 |
| multiple pseudomonas species secrete exolysin-like toxins and provoke caspase-1-dependent macrophage death. | pathogenic bacteria secrete protein toxins that provoke apoptosis or necrosis of eukaryotic cells. here, we developed a live-imaging method, based on incorporation of a dna-intercalating dye into membrane-damaged host cells, to study the kinetics of primary bone marrow-derived macrophages (bmdms) mortality induced by opportunistic pathogen pseudomonas aeruginosa expressing either type iii secretion system (t3ss) toxins or the pore-forming toxin, exolysin (exla). we found that exla promotes the a ... | 2017 | 28654176 |