| pediatric audio-visual fixation system. | | 2012 | 3578475 |
| [fetal catecholamines. clinical value of the findings in amniotic fluid]. | | 2012 | 3407864 |
| preventive medicine: osteoporosis. | | 2012 | 3350712 |
| chemotherapy of cancer of the colon and rectum. | | 2014 | 4260654 |
| [bilateral wrist fractures]. | | 2014 | 4017731 |
| phytosterolemia and hypercholesterolemia in childhood. | | 2014 | 3944712 |
| [history of cataract treatment]. | | 2015 | 4575472 |
| [60th birthday of prof. václav trnka, dr. sc]. | | 2015 | 4551569 |
| current reference works in public health. | | 2015 | 4557014 |
| nursing care study: secondary dementia. | | 2015 | 4486325 |
| a myoglobin-type haemoglobin of chironomus thummi thummi. | | 2015 | 4333654 |
| preparation of agar wells for antibiotic assay. | | 2016 | 4971723 |
| xenocin export by the flagellar type iii pathway in xenorhabdus nematophila. | the xenocin operon of xenorhabdus nematophila consists of xcia and ximb genes encoding a 64-kda xenocin and 42-kda immunity protein to kill competing microbes in the insect larva. the catalytic domain of xenocin has rnase activity and is responsible for its cytotoxicity. under sos conditions, xenocin is produced with immunity protein as a complex. here, we show that xenocin and immunity protein complex are exported through the flagellar type iii system of x. nematophila. secretion of xenocin com ... | 2013 | 23335409 |
| nild crispr rna contributes to xenorhabdus nematophila colonization of symbiotic host nematodes. | the bacterium xenorhabdus nematophila is a mutualist of entomopathogenic steinernema carpocapsae nematodes and facilitates infection of insect hosts. x. nematophila colonizes the intestine of s. carpocapsae which carries it between insects. in the x. nematophila colonization-defective mutant nild6::tn5, the transposon is inserted in a region lacking obvious coding potential. we demonstrate that the transposon disrupts expression of a single crispr rna, nild rna. a variant nild rna also is expres ... | 2014 | 25041533 |
| phospholipase a2 inhibitors synthesized by two entomopathogenic bacteria, xenorhabdus nematophila and photorhabdus temperata subsp. temperata. | the entomopathogenic bacteria xenorhabdus nematophila and photorhabdus temperata subsp. temperata suppress insect immune responses by inhibiting the catalytic activity of phospholipase a(2) (pla(2)), which results in preventing biosynthesis of immune-mediating eicosanoids. this study identified pla(2) inhibitors derived from culture broths of these two bacteria. both x. nematophila and p. temperata subsp. temperata culture broths possessed significant pla(2)-inhibitory activities. fractionation ... | 2012 | 22447611 |
| comparative analysis of xenorhabdus koppenhoeferi gene expression during symbiotic persistence in the host nematode. | species of xenorhabdus and photorhabdus bacteria form mutualistic associations with steinernema and heterorhabditis nematodes, respectively and serve as model systems for studying microbe-animal symbioses. here, we profiled gene expression of xenorhabdus koppenhoeferi during their symbiotic persistence in the newly formed infective juveniles of the host nematode steinernema scarabaei through the selective capture of transcribed sequences (scots). the obtained gene expression profile was then com ... | 2016 | 26745883 |
| mutational analyses reveal overall topology and functional regions of nilb, a bacterial outer membrane protein required for host association in a model of animal-microbe mutualism. | the gammaproteobacterium xenorhabdus nematophila is a mutualistic symbiont that colonizes the intestine of the nematode steinernema carpocapsae. nilb (nematode intestine localization) is essential for x. nematophila colonization of nematodes and is predicted to encode an integral outer membrane beta-barrel protein, but evidence supporting this prediction has not been reported. the function of nilb is not known, but when expressed with two other factors encoded by nila and nilc, it confers upon n ... | 2012 | 22287518 |
| computational analysis of bacterial rna-seq data. | recent advances in high-throughput rna sequencing (rna-seq) have enabled tremendous leaps forward in our understanding of bacterial transcriptomes. however, computational methods for analysis of bacterial transcriptome data have not kept pace with the large and growing data sets generated by rna-seq technology. here, we present new algorithms, specific to bacterial gene structures and transcriptomes, for analysis of rna-seq data. the algorithms are implemented in an open source software system c ... | 2013 | 23716638 |
| the global transcription factor lrp controls virulence modulation in xenorhabdus nematophila. | the bacterium xenorhabdus nematophila engages in phenotypic variation with respect to pathogenicity against insect larvae, yielding both virulent and attenuated subpopulations of cells from an isogenic culture. the global regulatory protein lrp is necessary for x. nematophila virulence and immunosuppression in insects, as well as colonization of the mutualistic host nematode steinernema carpocapsae, and mediates expression of numerous genes implicated in each of these phenotypes. given the centr ... | 2015 | 26170407 |
| candidate pathogenicity islands in the genome of 'candidatus rickettsiella isopodorum', an intracellular bacterium infecting terrestrial isopod crustaceans. | the bacterial genus rickettsiellabelongs to the order legionellales in the gammaproteobacteria, and consists of several described species and pathotypes, most of which are considered to be intracellular pathogens infecting arthropods. two members of this genus, r. grylliand r. isopodorum, are known to infect terrestrial isopod crustaceans. in this study, we assembled a draft genomic sequence for r. isopodorum, and performed a comparative genomic analysis with r. grylli. we found evidence for sev ... | 2016 | 28028472 |
| expression, purification, and functional characterization of atypical xenocin, its immunity protein, and their domains from xenorhabdus nematophila. | xenorhabdus nematophila, a gram-negative bacterium belonging to the family enterobacteriaceae is a natural symbiont of a soil nematode from the family steinernematidae. in this study cloning, expression, and purification of broad range iron regulated multidomain bacteriocin called xenocin from x. nematophila (66 kda, encoded by xcina gene) and its multidomain immunity protein (42 kda, encoded by ximb gene) have been done. xcina-ximb (n' terminal 270 bp), translocation, and translocation-receptor ... | 2013 | 26904727 |
| microbial population dynamics in the hemolymph of manduca sexta infected with xenorhabdus nematophila and the entomopathogenic nematode steinernema carpocapsae. | xenorhabdus nematophila engages in a mutualistic association with the nematode steinernema carpocapsae. the nematode invades and traverses the gut of susceptible insects. x. nematophila is released in the insect blood (hemolymph), where it suppresses host immune responses and functions as a pathogen. x. nematophila produces diverse antimicrobials in laboratory cultures. the natural competitors that x. nematophila encounters in the hemolymph and the role of antimicrobials in interspecies competit ... | 2014 | 24814780 |
| yaxab, a yersinia enterocolitica pore-forming toxin regulated by rova. | the transcriptional regulator rova positively regulates transcription of the yersinia enterocolitica virulence gene inv. invasin, encoded by inv, is important for establishment of y. enterocolitica infection. however, a rova mutant is more attenuated for virulence than an inv mutant, implying that rova regulates additional virulence genes. when the y. enterocolitica rova regulon was defined by microarray analysis, ye1984 and ye1985 were among the genes identified as being upregulated by rova. si ... | 2013 | 24002058 |
| activating and attenuating the amicoumacin antibiotics. | the amicoumacins belong to a class of dihydroisocoumarin natural products and display antibacterial, antifungal, anticancer, and anti-inflammatory activities. amicoumacins are the pro-drug activation products of a bacterial nonribosomal peptide-polyketide hybrid biosynthetic pathway and have been isolated from gram-positive bacillus and nocardia species. here, we report the stimulation of a "cryptic" amicoumacin pathway in the entomopathogenic gram-negative bacterium xenorhabdus bovienii, a stra ... | 2016 | 27347911 |
| a mixture of bacillus thuringiensis subsp. israelensis with xenorhabdus nematophila-cultured broth enhances toxicity against mosquitoes aedes albopictus and culex pipiens pallens (diptera: culicidae). | xenorhabdusandphotorhabdusspp. (enterobacteriaceae) can synthesize and release secondary metabolites that play crucial roles in their pathogenicity by suppressing the immunity of target insects. the insect immunity contributes to defense against the pathogenicity ofbacillus thuringiensis(bt). this study tested a hypothesis that bacterial immunosuppresants could enhance the susceptibility of mosquitoes (aedes albopictusandculex pipiens pallens) to bt. three symbiotic bacteria [x. nematophila(xn), ... | 2016 | 27018440 |
| development of a high efficient "dual bt-plus" insecticide using a primary form of an entomopathogenic bacterium, xenorhabdus nematophila. | a phase variation has been reported in an entomopathogenic bacterium, xenorhabdus nematophila. compared with a wild-type primary form, a secondary form usually loses several physiological and biochemical characters. this study showed that the phase variation of x. nematophila caused a significant alteration in its immunosuppressive activity and subsequent entomopathogenicity. a secondary form of x. nematophila was detected in laboratory colonies and exhibited significant differences in dye absor ... | 2014 | 24394195 |
| response of larval ephestia kuehniella (lepidoptera: pyralidae) to individual bacillus thuringiensis kurstaki toxins mixed with xenorhabdus nematophila. | bacillus thuringiensis kurstaki strain bns3 produces parasporal crystals formed by cry1aa, cry1ac and cry2aa delta-endotoxins. in a previous work, we showed that the latter exhibited individually, a weak insecticidal activity against ephestia kuehniella. in order to improve their toxicities, we studied the combined effect of each delta-endotoxin with x. nematophila cells on e. kuehniella larvae growth. xenorhabdus cells were used in combination with spore crystal mixture of the wild strain bns3, ... | 2013 | 23747825 |
| system wide analysis of the evolution of innate immunity in the nematode model species caenorhabditis elegans and pristionchus pacificus. | the evolution of genetic mechanisms used to combat bacterial infections is critical for the survival of animals and plants, yet how these genes evolved to produce a robust defense system is poorly understood. studies of the nematode caenorhabditis elegans have uncovered a plethora of genetic regulators and effectors responsible for surviving pathogens. however, comparative studies utilizing other free-living nematodes and therefore providing an insight into the evolution of innate immunity have ... | 2012 | 23028509 |
| inhibitory effect of xenorhabdus nematophila tb on plant pathogens phytophthora capsici and botrytis cinerea in vitro and in planta. | entomopathogenic bacteria xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. this study evaluated the inhibitory effect of x. nematophila tb culture on plant pathogens botrytis cinerea and phytophthora capsici. the cell-free filtrate of tb culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. the methanol-extracted bioactive compounds (methanol extract) of tb culture also had strong inhibitory ... | 2014 | 24599183 |
| role of secondary metabolites in establishment of the mutualistic partnership between xenorhabdus nematophila and the entomopathogenic nematode steinernema carpocapsae. | xenorhabdus nematophila engages in a mutualistic partnership with the nematode steinernema carpocapsae, which invades insects, migrates through the gut, and penetrates into the hemocoel (body cavity). we showed previously that during invasion of manduca sexta, the gut microbe staphylococcus saprophyticus appeared transiently in the hemocoel, while enterococcus faecalis proliferated as x. nematophila became dominant. x. nematophila produces diverse secondary metabolites, including the major water ... | 2015 | 25398871 |
| examining reaction specificity in pvcb, a source of diversity in isonitrile-containing natural products. | many bacteria produce isonitrile-containing natural products that are derived from aromatic amino acids. the synthetic clusters that control biosynthesis most commonly encode two enzymes, designated pvca and pvcb, as well as additional enzymes that direct synthesis of the natural product. the pvca enzyme installs the isonitrile moiety at the amino group of either tyrosine or tryptophan, as dictated by the particular pathway. the common pathway intermediate produced by pvca is directed toward dif ... | 2015 | 25866990 |
| biosynthesis of the antibiotic nematophin and its elongated derivatives in entomopathogenic bacteria. | nematophin, a known antibiotic natural product against staphylococcus aureus for almost 20 years, is produced by all strains of xenorhabdus nematophila. despite its simple structure, its biosynthesis was unknown. its biosynthetic pathway is reported using heterologous production in escherichia coli. additionally, the identification, structure elucidation, and biosynthesis of six extended nematophin derivatives from xenorhabdus pb62.4 carrying an additional valine are reported. preliminary bioact ... | 2017 | 28134534 |
| expression, purification, and functional analysis of novel rele operon from x. nematophila. | bacterial toxin-antitoxin (ta) complexes induce programmed cell death and also function to relieve cell from stress by various response mechanisms. escherichia coli relb-rele ta complex consists of a rele toxin functionally counteracted by relb antitoxin. in the present study, a novel homolog of rele toxin designated as xn-rele toxin from xenorhabdus nematophila possessing its own antitoxin designated as xn-releat has been identified. expression and purification of recombinant proteins under nat ... | 2014 | 25538952 |
| rapid determination of the amino acid configuration of xenotetrapeptide. | an e. coli strain with deletions in five transaminases (δaspc δilve δtyrb δavta δybfq) was constructed to be unable to degrade several amino acids. this strain was used as an expression host for the analysis of the amino acid configuration of nonribosomally synthesized peptides, including the novel peptide "xenotetrapeptide" from xenorhabdus nematophila, by using a combination of labeling experiments and mass spectrometry. additionally, the number of d-amino acids in the produced peptide was ass ... | 2014 | 24616055 |
| visualizing bacteria in nematodes using fluorescent microscopy. | symbioses, the living together of two or more organisms, are widespread throughout all kingdoms of life. as two of the most ubiquitous organisms on earth, nematodes and bacteria form a wide array of symbiotic associations that range from beneficial to pathogenic (1-3). one such association is the mutually beneficial relationship between xenorhabdus bacteria and steinernema nematodes, which has emerged as a model system of symbiosis (4). steinernema nematodes are entomopathogenic, using their bac ... | 2012 | 23117838 |
| small molecule perimeter defense in entomopathogenic bacteria. | two gram-negative insect pathogens, xenorhabdus nematophila and photorhabdus luminescens, produce rhabduscin, an amidoglycosyl- and vinyl-isonitrile-functionalized tyrosine derivative. heterologous expression of the rhabduscin pathway in escherichia coli, precursor-directed biosynthesis of rhabduscin analogs, biochemical assays, and visualization using both stimulated raman scattering and confocal fluorescence microscopy established rhabduscin's role as a potent nanomolar-level inhibitor of phen ... | 2012 | 22711807 |
| proteomic identification of a novel toxin protein (txp40) from xenorhabdus nematophila and its insecticidal activity against larvae of plutella xylostella. | for the identification of a novel insecticidal protein, a two-dimensional liquid chromatography (pf-2d) system was used in a quantitative proteomic analysis of xenorhabdus nematophila cbnu strain isolated from entomophagous nematode steinernema carpocapsae . protein patterns obtained from minimum and maximum insecticidal activities during cultivation were contrasted, and a novel toxin protein (txp40) was identified by maldi-tof/ms. the dna sequence of the cloned toxin gene (1089 bp) has an open ... | 2012 | 22352834 |
| effect of heat sterilization on the bioactivity of antibacterial metabolites secreted by xenorhabdus nematophila. | photorhabdus luminescens and xenorhabdus nematophila are entomopathogenic bacterial symbionts of beneficial nematodes heterorhabditis bacteriophora and steinernema carpocapsae, respectively. these bacterial symbionts are known to secrete an array of toxins, enzymes and antimicrobials that kill, bioconvert and protect the insect host for optimal nematode growth and reproduction. the present study explores heat stability of antibacterial metabolites secreted by x. nematophila. permeate of a liquid ... | 2012 | 24199479 |
| the global regulators lrp, leuo, and hexa control secondary metabolism in entomopathogenic bacteria. | photorhabdus luminescens tto1 and xenorhabdus nematophila hgb081 are insect pathogenic bacteria and producers of various structurally diverse bioactive natural products. in these entomopathogenic bacteria we investigated the role of the global regulators lrp, leuo, and hexa in the production of natural products. lrp is a general activator of natural product biosynthesis in x. nematophila and for most compounds in tto1. microarray analysis confirmed these results in x. nematophila and enabled the ... | 2017 | 28261170 |
| flagellar regulation and virulence in the entomopathogenic bacteria-xenorhabdus nematophila and photorhabdus luminescens. | there is a complex interplay between the regulation of flagellar motility and the expression of virulence factors in many bacterial pathogens. here, we review the literature on the direct and indirect roles of flagellar motility in mediating the tripartite interaction between entomopathogenic bacteria (photorhabdus and xenorhabdus), their nematode hosts, and their insect targets. first, we describe the swimming and swarming motility of insect pathogenic bacteria and its impact on insect coloniza ... | 2016 | 28091933 |
| larvicidal and growth-inhibitory activity of entomopathogenic bacteria culture fluids against aedes aegypti (diptera: culicidae). | dengue, chikungunya, and zika are important vector-borne diseases, and aedes aegypti l. is their main transmitter. as the disease management is mainly based on mosquito control strategies, the search for alternative and cost-effective approaches is ongoing. the gram-negative bacteria xenorhabdus nematophila and photorhabdus luminescens are symbiotically associated with entomopathogenic nematodes and are highly pathogenic for insect larvae. after we have recently confirmed the toxicity of these b ... | 2017 | 28062794 |
| oral toxicity of photorhabdus luminescens and xenorhabdus nematophila (enterobacteriaceae) against aedes aegypti (diptera: culicidae). | dengue fever is an important vector-borne disease, mainly transmitted by aedes aegypti. to date, there are no vaccines or effective drugs available against this arboviral disease. as mosquito control is practically the only method available to control dengue fever, alternative and cost-effective pest control strategies need to be explored. the gram-negative enteric bacteria xenorhabdus and photorhabdus are symbiotically associated with nematode parasites, which themselves are highly pathogenic f ... | 2013 | 23728731 |
| temperature effects on heterorhabditis megidis and steinernema carpocapsae infectivity to galleria mellonella. | the effect of temperature on the infection of larvae of the greater wax moth, galleria mellonella, by heterorhabditis megidis h90 and steinernema carpocapsae strain all, was determined. for both species, infection, reproduction, and development were fastest at 20 to 24 degrees c. infection by both h. megidis and s. carpocapsae occurred between 8 and 16 degrees c; however, neither species reproduced at 8 degrees c. among the nematodes used in experiments at 8 degrees c, no h. megidis and very few ... | 1999 | 19270900 |
| phospholipase a₂ inhibitors in bacterial culture broth enhance pathogenicity of a fungus nomuraea rileyi. | an entomopathogenic fungus, nomuraea rileyi, was isolated and its identity was confirmed by its internal transcribed spacer dna sequence. the isolated n. rileyi exhibited a specific pathogenicity to lepidopteran species. this study was focused on enhancing the fungal pathogenicity by using immunosuppressive agents. in response to infection of n. rileyi, spodoptera exigua larvae significantly induced catalytic activity of phospholipase a(2) (pla(2)) in three immune-associated tissues, namely hemo ... | 2012 | 22923114 |
| xenortide biosynthesis by entomopathogenic xenorhabdus nematophila. | the biosynthesis gene cluster of the xenortides and a new derivative, xenortide d, which is produced in only trace amounts, was identified in xenorhabdus nematophila. the structure of xenortide d was elucidated using a combination of labeling experiments followed by ms analysis and was confirmed by synthesis. bioactivity tests revealed a weak activity of tryptamine-carrying xenortides against plasmodium falciparum and trypanosoma brucei. | 2014 | 25080196 |
| pseudomonas brassicacearum strain df41 kills caenorhabditis elegans through biofilm-dependent and biofilm-independent mechanisms. | pseudomonas brassicacearum df41 is a biocontrol agent that suppresses disease caused by the fungal pathogen sclerotinia sclerotiorum a number of exometabolites are produced by df41 including the lipopeptide sclerosin, hydrogen cyanide (hcn) and degradative enzymes. production of these compounds is controlled at both the transcriptional and posttranscriptional level by quorum sensing (qs) and the gac-two component regulatory system. in order to be successful, a biocontrol agent must persist in th ... | 2016 | 27637885 |
| r-type bacteriocins in related strains of xenorhabdus bovienii: xenorhabdicin tail fiber modularity and contribution to competitiveness. | r-type bacteriocins are contractile phage tail-like structures that are bactericidal towards related bacterial species. the c-terminal region of the phage tail fiber protein determines target-binding specificity. the mutualistic bacteria xenorhabdus nematophila and x. bovienii produce r-type bacteriocins (xenorhabdicins) that are selectively active against different xenorhabdus species. we analyzed the p2-type remnant prophage clusters in draft sequences of nine strains of x. bovienii the c-term ... | 2017 | 27737947 |
| comparative analysis of p2-type remnant prophage loci in xenorhabdus bovienii and xenorhabdus nematophila required for xenorhabdicin production. | the xnp1 remnant p2-type prophage of xenorhabdus nematophila produces xenorhabdicin that is active against closely related species. xenorhabdicin had not been characterized previously in other xenorhabdus species. here, we show xenorhabdicin production in six different strains of xenorhabdus bovienii. the sequenced genome of x. bovienii ss-2004 was found to possess a highly conserved remnant p2-type cluster (xbp1). inactivation of the xbps1 sheath gene resulted in loss of bacteriocin activity, i ... | 2012 | 22612724 |
| rhabdopeptides as insect-specific virulence factors from entomopathogenic bacteria. | six novel linear peptides, named "rhabdopeptides", have been identified in the entomopathogenic bacterium xenorhabdus nematophila after the discovery of the corresponding rdp gene cluster by using a promoter trap strategy for the detection of insect-inducible genes. the structures of these rhabdopeptides were deduced from labeling experiments combined with detailed ms analysis. detailed analysis of an rdp mutant revealed that these compounds participate in virulence towards insects and are produ ... | 2013 | 24038745 |
| xenorhabdus japonicus sp. nov. associated with the nematode steinernema kushidai. | a new species, xenorhabdus japonicus, is proposed as the bacterial symbiont of steinernema kushidai isolated from field soil in shizuoka prefecture, japan. xenorhabdus japonicus could be distinguished phenotypically and genetically from other xenorhabdus spp. the type strain of the species, sk-1, a gram-negative, facultative anaerobe and peritrichously flagellated rod, has colonies with primary and secondary forms. the strain can be differentiated from the type strain of xenorhabdus nematophilus ... | 1994 | 24420949 |
| high levels of the xenorhabdus nematophila transcription factor lrp promote mutualism with steinernema carpocapsae nematode hosts. | xenorhabdus nematophila bacteria are mutualistic symbionts of steinernema carpocapsae nematodes and pathogens of insects. the x. nematophila global regulator lrp controls expression of many genes involved in both mutualism and pathogenic activities, suggesting a role in the transition between the two host organisms. we previously reported that natural populations of x. nematophila exhibit variable levels of lrp expression, and that cells expressing relatively low levels of lrp are optimized for ... | 2017 | 28389546 |
| the genome, transcriptome, and proteome of the nematode steinernema carpocapsae: evolutionary signatures of a pathogenic lifestyle. | the entomopathogenic nematode steinernema carpocapsae has been widely used for the biological control of insect pests. it shares a symbiotic relationship with the bacterium xenorhabdus nematophila, and is emerging as a genetic model to study symbiosis and pathogenesis. we obtained a high-quality draft of the nematode's genome comprising 84,613,633 bp in 347 scaffolds, with an n50 of 1.24 mb. to improve annotation, we sequenced both short and long rna and conducted shotgun proteomic analyses. s. ... | 2016 | 27876851 |
| nematode-bacteria mutualism: selection within the mutualism supersedes selection outside of the mutualism. | the coevolution of interacting species can lead to codependent mutualists. little is known about the effect of selection on partners within verses apart from the association. here, we determined the effect of selection on bacteria (xenorhabdus nematophila) both within and apart from its mutualistic partner (a nematode, steinernema carpocapsae). in nature, the two species cooperatively infect and kill arthropods. we passaged the bacteria either together with (m+), or isolated from (m-), nematodes ... | 2016 | 26867502 |
| effects of an entomopathogen nematode on the immune response of the insect pest red palm weevil: focus on the host antimicrobial response. | relationships between parasites and hosts can be drastic, depending on the balance between parasite strategies and the efficiency of the host immune response. in the case of entomopathogenic nematodes and their insect hosts, we must also consider the role of bacterial symbionts, as the interaction among them is tripartite and each component plays a critical role in death or survival. we analyzed the effects induced by the nematode-bacteria complex steinernema carpocapsae, against red palm weevil ... | 2016 | 26549224 |
| an improved method for generating axenic entomopathogenic nematodes. | steinernema carpocapsae are parasitic nematodes that invade and kill insects. the nematodes are mutualistically associated with the bacteria xenorhabdus nematophila and together form an excellent model to study pathogen infection processes and host anti-nematode/antibacterial immune responses. to determine the contribution of s. carpocapsae and their associated x. nematophila to the successful infection of insects as well as to investigate the interaction of each mutualistic partner with the ins ... | 2015 | 26386557 |
| a novel pilin subunit from xenorhabdus nematophila, an insect pathogen, confers pest resistance in tobacco and tomato. | overexpression of insecticidal pilin subunit from xenorhabdus nematophila protects transgenic tobacco and tomato plants against helicoverpa armigera. xenorhabdus nematophila is a pathogenic bacterium producing toxins that kill the larval host. previously, we characterized a pilin subunit of x. nematophila which was found to be a pore-forming toxin and cytotoxic to the larval hemocytes of helicoverpa armigera by causing agglutination and lysis of the cells. in the present study, we report the eff ... | 2015 | 26164296 |
| ectopic expression of groel from xenorhabdus nematophila in tomato enhances resistance against helicoverpa armigera and salt and thermal stress. | the groel homolog xngroel protein of xenorhabdus nematophila belongs to a highly conserved family of molecular chaperones/heat shock proteins (hsps). xngroel was shown to possess oral insecticidal activity against a major crop pest helicoverpa armigera. under normal conditions, the hsps/chaperones facilitate folding, assembly, and translocation of cellular proteins, while in stress conditions they protect proteins from denaturation. in this study, we describe generation of transgenic tomato plan ... | 2015 | 25958082 |
| draft genome sequence and annotation of the insect pathogenic bacterium xenorhabdus nematophila strain c2-3, isolated from nematode steinernema carpocapsae in the republic of korea. | xenorhabdus nematophila strain c2-3, which belongs to the family enterobacteriaceae, was isolated from entomopathogenic nematodes collected in the republic of korea. herein, we report a 4.38-mbp draft genome sequence of x. nematophila strain c2-3, with a 43.6% g+c content. the rast annotation analysis revealed 4,994 protein-coding sequences in the draft genome. | 2015 | 25676754 |
| variation in the susceptibility of drosophila to different entomopathogenic nematodes. | entomopathogenic nematodes (epns) in the genera heterorhabditis and steinernema are lethal parasites of insects that are of interest as models for understanding parasite-host interactions and as biocontrol agents for insect pests. epns harbor a bacterial endosymbiont in their gut that assists in insect killing. epns are capable of infecting and killing a wide range of insects, yet how the nematodes and their bacterial endosymbionts interact with the insect immune system is poorly understood. her ... | 2015 | 25561714 |
| a functional genomic screen for evolutionarily conserved genes required for lifespan and immunity in germline-deficient c. elegans. | the reproductive system regulates lifespan in insects, nematodes and vertebrates. in caenorhabditis elegans removal of germline increases lifespan by 60% which is dependent upon insulin signaling, nuclear hormone signaling, autophagy and fat metabolism and their microrna-regulators. germline-deficient c. elegans are also more resistant to various bacterial pathogens but the underlying molecular mechanisms are largely unknown. firstly, we demonstrate that previously identified genes that regulate ... | 2014 | 25093668 |
| physiological constants of the entomopathogenic bacterium xenorhabdus nematophila determined by microbial growth kinetics. | xenorhabdus nematophila, an entomopathogenic bacterium that symbiotically associates with the entomoparasitic nematode steinernema carpocapsae, was studied to determine its physiological parameters of glucose utilization. x. nematophila was cultured in chemically defined media containing various concentrations of glucose under optimal conditions utilizing a two-liter fermentation system. specific growth rates were obtained from each glucose batch. specific growth rates and their associated gluco ... | 2014 | 24944838 |
| sequential immunosuppressive activities of bacterial secondary metabolites from the entomopahogenic bacterium xenorhabdus nematophila. | the entomopathogenic bacterium xenorhabdus nematophila secretes at least eight bacterial metabolites that play crucial roles suppressing target insect immune responses by inhibiting eicosanoid biosynthesis. we analyzed sequential changes in bacterial metabolite production during bacterial growth and analyzed their individual immunosuppressive activities against the insect host, spodoptera exigua. x. nematophila exhibited a typical bacterial growth pattern in both insect host and culture medium, ... | 2014 | 24500481 |
| fliz is a global regulatory protein affecting the expression of flagellar and virulence genes in individual xenorhabdus nematophila bacterial cells. | heterogeneity in the expression of various bacterial genes has been shown to result in the presence of individuals with different phenotypes within clonal bacterial populations. the genes specifying motility and flagellar functions are coordinately regulated and form a complex regulon, the flagellar regulon. complex interplay has recently been demonstrated in the regulation of flagellar and virulence gene expression in many bacterial pathogens. we show here that fliz, a dna-binding protein, play ... | 2013 | 24204316 |
| biological responses of rhynchophorus ferrugineus (coleoptera: curculionidae) to steinernema carpocapsae (nematoda: steinernematidae). | rhynchophorus ferrugineus (olivier 1790) (coleoptera: curculionidae) is becoming a serious problem in mediterranean areas where it is well-adapted, and now is present even in the united states (california). the infestations are primarily in urban areas where chemical control is not advisable and million of euros are spent to control it. the effects of the entomopathogenic nematode steinernema carpocapsae (nematoda: steinernematidae) on mortality, growth, as well as the immune activity of r. ferr ... | 2013 | 24020269 |
| a novel insecticidal groel protein from xenorhabdus nematophila confers insect resistance in tobacco. | xenorhabdus nematophila is an entomopathogenic bacteria. it secretes a groel homolog, xngroel protein, toxic to its larval prey. groel belongs to the family of molecular chaperones and is required for proper folding of cellular proteins. oral ingestion of insecticidal xngroel protein is toxic to helicoverpa armigera, leading to cessation of growth and development of the larvae. in the present study, the insecticidal efficacy of xngroel against h. armigera has been evaluated in transgenic tobacco ... | 2014 | 23888329 |
| draft genome sequence and annotation of the entomopathogenic bacterium xenorhabdus nematophila strain f1. | we report the 4.3-mb genome sequence of xenorhabdus nematophila strain f1, a gram-negative bacterium that is a symbiont of the entomopathogenic nematode steinernema carpocapsae and pathogenic by direct injection for a wide variety of insects. | 2013 | 23788541 |
| an entomopathogenic bacterium, xenorhabdus nematophila, suppresses expression of antimicrobial peptides controlled by toll and imd pathways by blocking eicosanoid biosynthesis. | immune-associated genes of the beet armyworm, spodoptera exigua, were predicted from 454 pyrosequencing transcripts of hemocytes collected from fifth instar larvae challenged with bacteria. out of 22,551 contigs and singletons, 36% of the transcripts had at least one significant hit (e-value cutoff of 1e-20) and used to predict immune-associated genes implicated in pattern recognition, prophenoloxidase activation, intracellular signaling, and antimicrobial peptides (amps). immune signaling and a ... | 2013 | 23740621 |
| role of d535 and h538 in endogenous toxicity of xenocin from xenorhabdus nematophila. | bacteriocins are the toxic proteins produced by bacteria under stress condition to inhibit the growth of closely related bacterial strain(s). in our earlier study, purified recombinant xenocin-immunity protein complex from xenorhabdus nematophila showed detrimental effect on six different insect gut residing bacteria. in this study, endogenous toxicity assay with xcina and its catalytic domain under tightly regulated ara promoter was performed. multiple sequence alignment and homology modelling ... | 2013 | 23227808 |
| pepsin-like aspartic protease (sc-asp155) cloning, molecular characterization and gene expression analysis in developmental stages of nematode steinernema carpocapsae. | steinernema carpocapsae is an insect parasitic nematode associated with the bacterium xenorhabdus nematophila. these symbiotic complexes are virulent against the insect host. many protease genes were shown previously to be induced during parasitism, including one predicted to encode an aspartic protease, which was cloned and analyzed in this study. a cdna encoding sc-asp155 was cloned based on the est fragment. the full-length cdna of sc-asp155 consists of 955 nucleotides with multiple domains, ... | 2012 | 22503896 |
| cecropins as a marker of spodoptera frugiperda immunosuppression during entomopathogenic bacterial challenge. | an antimicrobial peptide (amp) of the cecropin family was isolated by hplc from plasma of the insect pest, spodoptera frugiperda. its molecular mass is 3910.9 da as determined by mass spectrometry. thanks to the est database spodobase, we were able to describe 13 cdnas encoding six different cecropins which belong to the sub-families ceca, cecb, cecc and cecd. the purified peptide identified as cecb1 was chemically synthesized (sycecb1). it was shown to be active against gram-positive and gram-n ... | 2012 | 22487443 |
| trade-offs shape the evolution of the vector-borne insect pathogen xenorhabdus nematophila. | our current understanding on how pathogens evolve relies on the hypothesis that pathogens' transmission is traded off against host exploitation. in this study, we surveyed the possibility that trade-offs determine the evolution of the bacterial insect pathogen, xenorhabdus nematophila. this bacterium rapidly kills the hosts it infects and is transmitted from host cadavers to new insects by a nematode vector, steinernema carpocapsae. in order to detect trade-offs in this biological system, we pro ... | 2012 | 22398163 |
| effects of temperature and dietary lipids on phospholipid fatty acids and membrane fluidity in steinernema carpocapsae. | the phospholipid composition of steinernema carpocapsae was studied in relation to diet and culture temperature. when reared at 18 and 27.5 c on galleria mellonella or on an artificial diet supplemented with lard, linseed oil, or fish oil as lipid sources, nematode phospholipids contained an abundance of 20-carbon polyunsaturated fatty acids, with eicosapentaenoic acid (20:5(n - 3)) predominant, regardless of the fatty acid composition of the diet. because the level of linolenic acid (18:3(n - 3 ... | 1994 | 19279893 |
| dendroctonus frontalis infection by the dd-136 strain of neoaplectana carpocapsae and its bacterial complex. | the dd-136 strain of neoaplectana carpocapsae weiser (steinernematidae) after spray application to pine bark in 0.1% formalin plus wetting agent entered pine bark beetle tunnels and killed 44% of the brood and adults of dendroctonus frontalis zimmermann at 18 and 26 c, 60% relative hummidity and at ambient temperatures and humidities. | 1970 | 19322322 |