| physical stress primes the immune response of galleria mellonella larvae to infection by candida albicans. | larvae of the greater wax moth (galleria mellonella) that had been subjected to physical stress by shaking in cupped hands for 2 min showed reduced susceptibility to infection by candida albicans when infected 24 h after the stress event. physically stressed larvae demonstrated an increase in haemocyte density and elevated mrna levels of galiomicin and an inducible metalloproteinase inhibitor (impi) but not transferrin or gallerimycin. in contrast, previous work has demonstrated that microbial p ... | 2008 | 18457977 |
| immunosuppressive effect of cyclosporin a on insect humoral immune response. | cyclosporin a suppressed humoral immune response of galleria mellonella larvae. insects were immunized with lps pseudomonas aeruginosa and then injected with cyclosporin a. immunosuppressive effects were expressed both, in larvae treated with cyclosporin a at the initial phase of immune response and at the effector phase of antibacterial immunity. cyclosporin a moderately decreased lysozyme activity and significantly decreased antibacterial activity peptides against escherichia coli. immunosuppr ... | 2008 | 18472108 |
| molecular analysis of a novel gene cluster encoding an insect toxin in plant-associated strains of pseudomonas fluorescens. | pseudomonas fluorescens cha0 and the related strain pf-5 are well-characterized representatives of rhizosphere bacteria that have the capacity to protect crop plants from fungal root diseases, mainly by releasing a variety of exoproducts that are toxic to plant pathogenic fungi. here, we report that the two plant-beneficial pseudomonads also exhibit potent insecticidal activity. anti-insect activity is linked to a novel genomic locus encoding a large protein toxin termed fit (for p. fluorescensi ... | 2008 | 18484997 |
| photorhabdus luminescens genes induced upon insect infection. | photorhabdus luminescens is a gram-negative luminescent enterobacterium and a symbiote to soil nematodes belonging to the species heterorhabditis bacteriophora. p.luminescens is simultaneously highly pathogenic to insects. this bacterium exhibits a complex life cycle, including one symbiotic stage characterized by colonization of the upper nematode gut, and a pathogenic stage, characterized by release from the nematode into the hemocoel of insect larvae, resulting in rapid insect death caused by ... | 2008 | 18489737 |
| changes in galleria mellonella lysozyme level and activity during pseudomonas aeruginosa infection. | the level of lysozyme in fat body, hemocytes and cell-free hemolymph from galleria mellonella larvae infected with pseudomonas aeruginosa was determined and evaluated. in the samples of fat body and hemocytes, an increase in lysozyme content was detected 1 d after infection and then a significant decrease was observed after a prolonged infection time. in the case of cell-free hemolymph, an increase in the lysozyme level was noticeable during the first 30 h post injection and stayed at a similar ... | 2008 | 18500634 |
| the cuticular fatty acids of calliphora vicina, dendrolimus pini and galleria mellonella larvae and their role in resistance to fungal infection. | epicuticular lipids in many terrestrial arthropods consist of vast numbers of polar and non-polar aliphatic compounds, which are mainly responsible for the water balance in these animals but can also affect conidia germination of entomopathogenic fungi. in this work the qualitative and quantitative profiles of cuticular fatty acids from three insect species differing in their susceptibility to fungal infection were studied. in an innovative approach, laser light scattering detection was coupled ... | 2008 | 18510973 |
| role of symbiotic and non-symbiotic bacteria in carbon dioxide production from hosts infected with steinernema riobrave. | entomopathogenic nematodes of the family steinernematidae and their mutualistic bacteria (xenorhabdus spp.) are lethal endoparasites of insects. we hypothesized that growth of the nematode's mutualistic bacteria in the insect host may contribute to the production of cues used by the infective juveniles (ijs) in responding to potential hosts for infection. specifically, we tested if patterns of bacterial growth could explain differences in co2 production over the course of host infection. growth ... | 2008 | 18621386 |
| the isolation and characterization of the mp and fp plaque variants of galleria mellonella nuclear polyhedrosis virus. | two plaque morphologies were detected in assays of galleria mellonella nuclear polyhedrosis virus preparations which had been serially passaged in the tn-368 cell line. the fp (few polyhedra) plaques were larger (0.7-mm average diameter) and the infected cells contained less than 10 polyhedra each. the mp (many polyhedra) plaques were smaller (0.5-mm average diameter), and the infected cells contained greater than 10 each. only the fp variant could be purified by plaque picking and remained pure ... | 1982 | 18635122 |
| [purification and characterization of the haemocoel insecticide tp40 from xenorhabdus nematophila]. | xenorhabdus nematophila is an insect pathogen bacterium symbiotically associated with entomopathogenic nematode. the bacteria produce a number of toxins to overcome immune response of insect hosts and kill their hosts. we purified a novel haemocoel insecticidal protein from x. nematophila hb310, cloned and analysed gene sequence of this novel protein. | 2008 | 18652303 |
| host-derived extracellular nucleic acids enhance innate immune responses, induce coagulation, and prolong survival upon infection in insects. | extracellular nucleic acids play important roles in human immunity and hemostasis by inducing ifn production, entrapping pathogens in neutrophil extracellular traps, and providing procoagulant cofactor templates for induced contact activation during mammalian blood clotting. in this study, we investigated the functions of extracellular rna and dna in innate immunity and hemolymph coagulation in insects using the greater wax moth galleria mellonella a reliable model host for many insect and human ... | 2008 | 18684961 |
| insecticidal evaluation of beauveria bassiana engineered to express a scorpion neurotoxin and a cuticle degrading protease. | to improve the insecticidal efficacy of the entomopathogen beauveria bassiana, the fungus was genetically modified with an insect-specific scorpion neurotoxin aait and an insect cuticle degrading protease pr1a from another insect pathogen (metarhizium anisopliae). the wild-type and the transformants were bioassayed against the larvae of masson's pine caterpillar dendrolimus punctatus and the wax moth galleria mellonella. in comparison to the wild-type strain, engineered isolates took fewer spore ... | 2008 | 18800183 |
| age and sex related variations in protein and carbohydrate levels of galleria mellonella (linnaeus, 1758) (lepidoptera: pyralidae) in constant lightness and darkness. | variations in protein and carbohydrate levels correlated with the age and sex of galleria mellonella (linnaeus, 1758) (lepidoptera: pyralidae) in constant lightness and darkness were investigated. tests were conducted under laboratory conditions at 28 +/- 2 degrees c temperature and 65 +/- 5% relative humidity. insects were fed on combs without honey. protein level in 100 mg of adults increased in the first days of adult life of females in connection with their age and then decreased. no differe ... | 2008 | 18819569 |
| the yvftu two-component system is involved in plcr expression in bacillus cereus. | most extracellular virulence factors produced by bacillus cereus are regulated by the pleiotropic transcriptional activator plcr. among strains belonging to the b. cereus group, the plcr gene is always located in the vicinity of genes encoding the yvftu two-component system. the putative role of yvftu in the expression of the plcr regulon was therefore investigated. | 2008 | 18925929 |
| to complete their life cycle, pathogenic nematode-bacteria complexes deter scavengers from feeding on their host cadaver. | the life cycle of commercially used molluscicidal rhabditid nematodes phasmarhabditis hermaphrodita and entomopathogenic steinernematid nematodes is similar: infective stages carry symbiotic bacteria, which kill their host. nematodes complete their life cycle feeding on the proliferating symbiont and the host tissue. after 1-2 weeks, new infective stages carrying the bacteria leave the host cadaver in search of new hosts. the removal of invertebrate cadavers by scavengers is extremely fast and r ... | 2009 | 18977420 |
| antibacterial activity in vivo and in vitro in the hemolymph of galleria mellonella infected with pseudomonas aeruginosa. | the antibacterial activity of hemolymph from galleria mellonella infected with entomopathogenic strain of pseudomonas aeruginosa and non-pathogenic bacterium escherichia coli was studied. in vivo, the antimicrobial activity appeared shortly after p. aeruginosa infection, reached the maximum level 18 h postinjection, while 30 h later only trace activity was noted. the activity induced by e. coli sustained on the high level until 48 h after infection. we also noted that the antimicrobial activity ... | 2009 | 18996217 |
| an alternative insect pathogenic strategy in an aspergillus flavus auxotroph. | in order to study fungal pathogen evolution, we used a model system whereby the opportunistic fungus aspergillus flavus was serially propagated through the insect (galleria mellonella) larvae, yielding a cysteine/methionine auxotroph of a. flavus with properties of an obligate insect pathogen. the auxotroph exhibited insect host restriction but did not show any difference in virulence when compared with the wild-type (scully lr, bidochka mj, 2006. microbiology 152, 223-232). here, we report that ... | 2009 | 19028580 |
| predation by podisus maculiventris (say) (hemiptera: pentatomidae) on viburnum leaf beetle, pyrrhalta viburni (paykull) (coleoptera: chrysomelidae), under laboratory and field conditions. | to evaluate the potential of podisus maculiventris (say) (heteroptera: pentatomidae) as a biological control agent against viburnum leaf beetle, pyrrhalta viburni (paykull) (coleoptera: chrysomelidae), laboratory trials were conducted to measure prey consumption of p. maculiventris over nymphal development. field trials tested the impact of augmentative releases of p. maculiventris nymphs on populations of p. viburni, using both open shrubs and caged branches of viburnum trilobum. in the laborat ... | 2008 | 19036203 |
| potential of two entomopathogenic nematodes for suppression of plum curculio (conotrachelus nenuphar, coleoptera: curculionidae) life stages in northern climates. | plum curculio, conotrachelus nenuphar, is a major pest of pome and stone fruits in north america. we evaluated the potential efficacy of two entomopathogenic nematode species for suppression of plum curculio in northern regions, targeting life stages that reside in soil during spring and summer. a strain of heterorhabditis bacteriophora isolated from soil infested with plum curculio in northern utah and a commercially available strain of steinernema feltiae known to tolerate cool temperatures we ... | 2008 | 19036207 |
| insecticidal genes of yersinia spp.: taxonomical distribution, contribution to toxicity towards manduca sexta and galleria mellonella, and evolution. | toxin complex (tc) proteins termed tcaabc, tcdab, and tccabc with insecticidal activity are present in a variety of bacteria including the yersiniae. | 2008 | 19063735 |
| use of galleria mellonella larvae to evaluate the in vivo anti-fungal activity of [ag2(mal)(phen)3]. | larvae of the insect galleria mellonella were employed to assess the in vivo antifungal efficacy of ([ag(2)(mal)(phen)(3)]), agno(3) and 1,10-phenanthroline. larvae pre-inoculated with these compounds were protected from a subsequent lethal infection by the yeast candida albicans while larvae inoculated 1 and 4 h post-infection showed significantly increased survival (p < 0.01) compared to control larvae. administration of these compounds resulted in an increase over 48 h in the density of insec ... | 2009 | 19082779 |
| reduced susceptibility to vancomycin influences pathogenicity in staphylococcus aureus infection. | in the present study, we demonstrated the utility of the nonmammalian model system galleria mellonella for studying the pathogenesis of staphylococcus aureus infection. by use of clinical and laboratory strains that had been exposed to vancomycin, we showed that both agr functional status and vancomycin minimum inhibitory concentration are determinants associated with the virulence of s. aureus in g. mellonella. these results show that g. mellonella can be effectively used to facilitate the in v ... | 2009 | 19125671 |
| conidiation color mutants of aspergillus fumigatus are highly pathogenic to the heterologous insect host galleria mellonella. | the greater wax moth galleria mellonella has been widely used as a heterologous host for a number of fungal pathogens including candida albicans and cryptococcus neoformans. a positive correlation in pathogenicity of these yeasts in this insect model and animal models has been observed. however, very few studies have evaluated the possibility of applying this heterologous insect model to investigate virulence traits of the filamentous fungal pathogen aspergillus fumigatus, the leading cause of i ... | 2009 | 19156203 |
| an fmlp receptor is involved in activation of phagocytosis by hemocytes from specific insect species. | in mammalian phagocytes, the bacterial formylated peptide fmlp functions both as a potent enhancer of phagocytosis and chemoattractant. fmlp has been reported to be chemotactic for hemocytes of two marine invertebrates, and of the insect manduca sexta (lepidoptera). whether fmlp is also able to activate phagocytosis has not been explored in hemocytes of any invertebrate. to determine the effect of fmlp on insect hemocyte phagocytosis, in vitro phagocytosis assays were performed with hemocytes fr ... | 2009 | 19166874 |
| hd-gyp domain proteins regulate biofilm formation and virulence in pseudomonas aeruginosa. | hd-gyp is a protein domain involved in the hydrolysis of the bacterial second messenger cyclic-di-gmp. the genome of the human pathogen pseudomonas aeruginosa pao1 encodes two proteins (pa4108, pa4781) with an hd-gyp domain and a third protein, pa2572, which contains a domain with variant key residues (yn-gyp). here we have investigated the role of these proteins in biofilm formation, virulence factor synthesis and virulence of p. aeruginosa. mutation of pa4108 and pa4781 led to an increase in t ... | 2009 | 19170727 |
| harnessing hsp90 function as a powerful, broadly effective therapeutic strategy for fungal infectious disease. | invasive fungal infections are a leading cause of mortality among immunocompromised individuals. treatment is notoriously difficult with the limited armamentarium of antifungal drugs, whose efficacy is compromised by host toxicity, a limited activity spectrum, or the emergence of drug resistance. we previously established that the molecular chaperone hsp90 enables the emergence and maintenance of fungal drug resistance. for the most prevalent fungal pathogen of humans, candida albicans, hsp90 me ... | 2009 | 19196973 |
| experimental bacteriophage therapy increases survival of galleria mellonella larvae infected with clinically relevant strains of the burkholderia cepacia complex. | the burkholderia cepacia complex (bcc) is a group of bacterial pathogens that are highly antibiotic resistant and associated with debilitating respiratory infections. although bacteriophages of the bcc have been isolated and characterized, no studies have yet examined phage therapy against the bcc in vivo. in a caterpillar infection model, we show that bcc phage therapy is an alternative treatment possibility and is highly effective under specific conditions. | 2009 | 19223640 |
| humoral immune response of galleria mellonella larvae after infection by beauveria bassiana under optimal and heat-shock conditions. | natural infection of galleria mellonella larvae with the entomopathogenic fungus beauveria bassiana led to antifungal, but not antibacterial host response. this was manifested by induction of gallerimycin and galiomicin gene expression and, consequently, the appearance of antifungal activity in the hemolymph of the infected larvae. the activity of lysozyme increased at the beginning of infection and dropped while infection progressed. exposure of the naturally infected animals to 43 degrees c fo ... | 2009 | 19232408 |
| recycling potential and fitness of steinernematid nematodes cultured in curculio caryae and galleria mellonella. | the recycling potential of entomopathogenic nematodes in the pecan weevil, curculio caryae, following inundative applications is an important factor in considering whether nematodes could be incorporated into a c. caryae management strategy. our objective was to determine the recycling potential and fitness of steinernema carpocapsae and s. riobrave cultured in c. caryae. to estimate fitness and quality, we reared nematodes in larvae of c. caryae and in the commonly used standard host, the great ... | 2005 | 19262838 |
| insecticidal toxic proteins produced by photorhabdus luminescens akhurstii, a symbiont of heterorhabditis indica. | we describe the isolation and characterization of an insect pathogenic bacterium from the entomopathogenic nematode heterorhabditis indica (karnataka strain), an isolate from the southern regions of india. the strain has been identified and characterized by phenotypic, biochemical tests and pcr-rflp analysis of the 16s rrna gene as photorhabdus luminescens subsp. akhurstii. the insecticidal toxin complex produced by this bacterium has been purified through a series of steps including ultrafiltra ... | 2002 | 19265903 |
| effect of entomopathogenic nematodes and trichoderma harzianum on the strawberry black root rot pathogens pratylenchus penetrans and rhizoctonia fragariae. | the effects of inundative releases of entomopathogenic steinernema carpocapsae and s. feltiae infective juveniles and applications of the biological control fungus trichoderma harzianum t-22 (rootshield) on pratylenchus penetrans and strawberry black root rot caused by rhizoctonia fragariae were determined in field microplots and small plots. entomopathogenic nematodes were applied as a soil drench at rates of 7.4 or 14.8 billion per ha in may or august for 3 years. rootshield was applied as cro ... | 2002 | 19265955 |
| effects of culture method and formulation on the virulence of steinernema riobrave (rhabditida: steinernematidae) to diaprepes abbreviatus (coleoptera: curculionidae). | the diaprepes root weevil, diaprepes abbreviatus, is a pest of vegetables, ornamental plants, sugarcane, and citrus in florida and the caribbean. the entomopathogenic nematode, steinernema riobrave, can reduce larval populations of d. abbreviatus substantially. efficacy of entomopathogenic nematodes, however, may be affected by culture method and formulation. using d. abbreviatus as the host, we compared the efficacy of two commercial s. riobrave formulations, a liquid and a waterdispersible gra ... | 2000 | 19270978 |
| foliar sprays with steinernema carpocapsae against early-season apple pests. | persistence and field efficacy of the entomopathogenic nematode steinernema carpocapsae a11 strain applied by foliar sprays were evaluated against the apple sawfly hoplocampa testudinea and the plum curculio conotrachelus nenuphar, two early-season pests in quebec apple orchards. from 1992 to 1995, bioassays with galleria mellonella larvae were conducted to assess the persistence of s. carpocapsae on leaves, flower clusters, and twigs up to 4 days after evening application. s. carpocapsae juveni ... | 1998 | 19274253 |
| biological control of the pecan weevil, curculio caryae (coleoptera: curculionidae), with entomopathogenic nematodes. | steinernema carpocapsae (weiser) strain a11, s. feltiae (filipjev) strain sn, and heterorhabditis bacteriophora poinar strains hp88 and georgia were tested for their efficacy as biological control agents of the pecan weevil, curculio caryae (horn), in pecan orchard soil-profile containers under greenhouse conditions. percentage c. caryae parasitism by s. carpocapsae and h. bacteriophora strain hp88 and georgia was consistently poor when applied either prior to or following c. caryae entry into t ... | 1993 | 19279746 |
| quantification of invasion of two strains of steinernema carpocapsae (weiser) into three lepidopteran larvae. | studies with last instar larvae of the fall armyworm, spodoptera frugiperda (j. e. smith), the black cutworm, agrotis ipsilon (hufnagel), and the greater wax moth, galleria mellonella (l.) were used to quantify the invasive ability of two strains (all and mexican) of steinernema carpocapsae and to determine how factors in the bioassay procedure affect both nematode invasion and host mortality. nematode invasive ability was variable, with 10-50% of nematodes successfully infecting the host. the p ... | 1993 | 19279755 |
| natural occurrence of entomogenous nematodes in tennessee nursery soils. | to isolate potential insect biocontrol agents, entomogenous nematodes were surveyed in tennessee plant nurseries in 1991. soil samples from 113 nursery sites were baited with greater wax moth (galleria mellonella) larvae, house cricket (acheta domesticus) adults, lesser mealworm (alphitobius diaperings) adults, and house fly (musca domestica) larvae. heterorhabditis bacteriophora and steinernema carpocapsae were each recovered from 17 soil samples. heterorhabditis bacteriophora was more common i ... | 1993 | 19279756 |
| dose-dependent cellular and humoral responses in galleria mellonella larvae following beta-glucan inoculation. | galleria mellonella larvae were inoculated with different doses of beta-glucan by injection into the haemocoel. those larvae that had received high doses of beta-glucan (15, 30 or 60microg/larva) demonstrated increased survival following infection with the yeast candida albicans. high concentrations of glucan induced an increase in haemocyte density and a reduction in yeast proliferation within the haemocoel. proteomic analysis of glucan-treated larvae revealed increased expression of a variety ... | 2010 | 19925881 |
| galleria mellonella as a model system for studying listeria pathogenesis. | essential aspects of the innate immune response to microbial infection are conserved between insects and mammals. this has generated interest in using insects as model organisms to study host-microbe interactions. we used the greater wax moth galleria mellonella, which can be reared at 37 degrees c, as a model host for examining the virulence potential of listeria spp. here we report that galleria is an excellent surrogate model of listerial septic infection, capable of clearly distinguishing be ... | 2010 | 19897755 |
| 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 |
| virulence of enterococcus faecalis dairy strains in an insect model: the role of fsrb and gele. | despite the existence of various virulence factors in the enterococcus genus, enterococcal virulence is still a debated issue. a main consideration is the detection of the same virulence genes in strains isolated from nosocomial or community-acquired infections, and from food products. the goal of this study was to evaluate the roles of two well-characterized enterococcal virulence factors, fsr and gelatinase, in the potential virulence of enterococcus faecalis food strains. virulence of unrelat ... | 2009 | 19696101 |
| spores as infectious propagules of cryptococcus neoformans. | cryptococcus neoformans and cryptococcus gattii are closely related pathogenic fungi that cause pneumonia and meningitis in both immunocompromised and immunocompetent hosts and are a significant global infectious disease risk. both species are found in the environment and are acquired via inhalation, leading to an initial pulmonary infection. the infectious propagule is unknown but is hypothesized to be small desiccated yeast cells or spores produced by sexual reproduction (opposite- or same-sex ... | 2009 | 19620339 |
| galleria mellonella as a model system to study acinetobacter baumannii pathogenesis and therapeutics. | nonmammalian model systems of infection such as galleria mellonella (caterpillars of the greater wax moth) have significant logistical and ethical advantages over mammalian models. in this study, we utilize g. mellonella caterpillars to study host-pathogen interactions with the gram-negative organism acinetobacter baumannii and determine the utility of this infection model to study antibacterial efficacy. after infecting g. mellonella caterpillars with a reference a. baumannii strain, we observe ... | 2009 | 19332683 |
| survey of heterorhabditidae and steinernematidae (rhabditida, nematoda) in western canada. | a survey was done in the summer months along the alaska highway, in other parts of british columbia, in northern alberta, and in the yukon territory for steinernematid and heterorhabditid nematodes occurring in the top 10 cm of soil. steinernema feltiae and steinernema spp. were found at 18 and heterorhabditis megidis at 7 sites of 125 sampled. most nematodes were found where visible insect infestation occurred and where human influence on the habitat was substantial (e.g., agricultural, foreste ... | 1993 | 19279830 |
| septins enforce morphogenetic events during sexual reproduction and contribute to virulence of cryptococcus neoformans. | septins are conserved, cytoskeletal gtpases that contribute to cytokinesis, exocytosis, cell surface organization and vesicle fusion by mechanisms that are poorly understood. roles of septins in morphogenesis and virulence of a human pathogen and basidiomycetous yeast cryptococcus neoformans were investigated. in contrast to a well-established paradigm in s. cerevisiae, cdc3 and cdc12 septin homologues are dispensable for growth in c. neoformans yeast cells at 24 degrees c but are essential at 3 ... | 2010 | 19943902 |
| inactivation of burkholderia cepacia complex phage ks9 gp41 identifies the phage repressor and generates lytic virions. | the burkholderia cepacia complex (bcc) is made up of at least 17 species of gram-negative opportunistic bacterial pathogens that cause fatal infections in patients with cystic fibrosis and chronic granulomatous disease. ks9 (vb_bcens_ks9), one of a number of temperate phages isolated from bcc species, is a prophage of burkholderia pyrrocinia lmg 21824. transmission electron micrographs indicate that ks9 belongs to the family siphoviridae and exhibits the b1 morphotype. the 39,896-bp ks9 genome, ... | 2010 | 19939932 |
| organization and evolutionary trajectory of the mating type (mat) locus in dermatophyte and dimorphic fungal pathogens. | sexual reproduction in fungi is governed by a specialized genomic region, the mating type (mat) locus, whose gene identity, organization, and complexity are diverse. we identified the mat locus of five dermatophyte fungal pathogens (microsporum gypseum, microsporum canis, trichophyton equinum, trichophyton rubrum, and trichophyton tonsurans) and a dimorphic fungus, paracoccidioides brasiliensis, and performed phylogenetic analyses. the identified mat locus idiomorphs of m. gypseum control cell t ... | 2010 | 19880755 |
| examination of xenorhabdus nematophila lipases in pathogenic and mutualistic host interactions reveals a role for xlpa in nematode progeny production. | xenorhabdus nematophila is a gammaproteobacterium and broad-host-range insect pathogen. it is also a symbiont of steinernema carpocapsae, the nematode vector that transports the bacterium between insect hosts. x. nematophila produces several secreted enzymes, including hemolysins, lipases, and proteases, which are thought to contribute to virulence or nutrient acquisition for the bacterium and its nematode host in vivo. x. nematophila has two lipase activities with distinct in vitro specificitie ... | 2010 | 19880652 |
| the dlt operon of bacillus cereus is required for resistance to cationic antimicrobial peptides and for virulence in insects. | the dlt operon encodes proteins that alanylate teichoic acids, the major components of cell walls of gram-positive bacteria. this generates a net positive charge on bacterial cell walls, repulsing positively charged molecules and conferring resistance to animal and human cationic antimicrobial peptides (amps) in gram-positive pathogenic bacteria. amps damage the bacterial membrane and are the most effective components of the humoral immune response against bacteria. we investigated the role of t ... | 2009 | 19767427 |
| phase variation has a role in burkholderia ambifaria niche adaptation. | members of the burkholderia cepacia complex (bcc), such as b. ambifaria, are effective biocontrol strains, for instance, as plant growth-promoting bacteria; however, bcc isolates can also cause severe respiratory infections in people suffering from cystic fibrosis (cf). no distinction is known between isolates from environmental and human origins, suggesting that the natural environment is a potential source of infectious bcc species. while investigating the presence and role of phase variation ... | 2010 | 19710710 |
| insect infection model for campylobacter jejuni reveals that o-methyl phosphoramidate has insecticidal activity. | galleria mellonella (wax moth) larvae have elsewhere been shown to be susceptible to pathogens such as francisella tularensis, burkholderia mallei, and pseudomonas aeruginosa. we report that the larvae are rapidly killed by campylobacter jejuni at 37c. three strains of c. jejuni tested, 11168h (human diarrheal isolate), g1 (human guillain-barré syndrome isolate), and 81-176 (human diarrheal isolate), were equally effective at killing g. mellonella larvae. a panel of defined mutants of c. jejuni ... | 2010 | 20113177 |
| the (p)ppgpp synthetase rela contributes to stress adaptation and virulence in enterococcus faecalis v583. | guanosine penta- and tetraphosphate [(p)ppgpp] are two unusual nucleotides implied in the bacterial stringent response. in many pathogenic bacteria, mutants unable to synthesize these molecules lose their virulence. in gram-positive bacteria such as enterococcus faecalis, the synthesis and degradation of (p)ppgpp mainly depend on the activity of a bifunctional enzyme, encoded by the rela gene. by analysing deltarela and deltarelq (which encodes a protein harbouring a ppgpp synthetase activity) d ... | 2009 | 19608607 |
| astemizole and an analogue promote fungicidal activity of fluconazole against cryptococcus neoformans var. grubii and cryptococcus gattii. | cryptococcus neoformans is the leading cause of fungal meningitis, a life-threatening infection that occurs predominately in immuocompromised patients. current drug therapies are limited to amphotericin b, flucytosine and the azoles since the echinocandins have no demonstrated activity against yeast like pathogens. fluconazole, a drug belonging to the azole class and often the only available antifungal in the developing world, is fungistatic and therefore not effective in clearing cryptococcal i ... | 2010 | 19572230 |
| mixed infection of galleria mellonella with two entomopathogenic nematode (nematoda: rhabditida) species: steinernema affine benefits from the presence of steinernema kraussei. | the interactions of two sympatric entomopathogenic nematodes steinernema affine and steinernema. kraussei were studied in a series of laboratory experiments. single species, simultaneous and sequential infections of galleria mellonella were performed in eppendorf tubes and the invasion rate, nematode progeny production and the number of hosts producing nematode progeny were observed. the invasion rate of s. affine was not affected by the mixed infection whereas the invasion of the latter species ... | 2009 | 19531365 |
| identification of specific and universal virulence factors in burkholderia cenocepacia strains by using multiple infection hosts. | over the past few decades, strains of the burkholderia cepacia complex have emerged as important pathogens for patients suffering from cystic fibrosis. identification of virulence factors and assessment of the pathogenic potential of burkholderia strains have increased the need for appropriate infection models. in previous studies, different infection hosts, including mammals, nematodes, insects, and plants, have been used. at present, however, the extent to which the virulence factors required ... | 2009 | 19528212 |
| gut bacteria are not required for the insecticidal activity of bacillus thuringiensis toward the tobacco hornworm, manduca sexta. | it was recently proposed that gut bacteria are required for the insecticidal activity of the bacillus thuringiensis-based insecticide, dipel, toward the lepidopterans manduca sexta, pieris rapae, vanessa cardui, and lymantria dispar. using a similar methodology, it was found that gut bacteria were not required for the toxicity of dipel or cry1ac or for the synergism of an otherwise sublethal concentration of cry1ac toward m. sexta. the toxicities of dipel and of b. thuringiensis hd73 cry(-) spor ... | 2009 | 19525273 |
| ace, which encodes an adhesin in enterococcus faecalis, is regulated by ers and is involved in virulence. | enterococcus faecalis is an opportunistic pathogen that causes numerous infectious diseases in humans and is a major agent of nosocomial infections. in this work, we showed that the recently identified transcriptional regulator ers (prfa like), known to be involved in the cellular metabolism and the virulence of e. faecalis, acts as a repressor of ace, which encodes a collagen-binding protein. we characterized the promoter region of ace, and transcriptional analysis by reverse transcription-quan ... | 2009 | 19433548 |
| juvenile hormone binding protein traffic -- interaction with atp synthase and lipid transfer proteins. | juvenile hormone (jh) controls insect development, metamorphosis and reproduction. in insect hemolymph a significant proportion of jh is bound to juvenile hormone binding protein (jhbp), which serves as a carrier supplying the hormone to the target tissues. to shed some light on jhbp passage within insect tissues, the interaction of this carrier with other proteins from galleria mellonella (lepidoptera) was investigated. our studies revealed the presence of jhbp within the tracheal epithelium an ... | 2009 | 19426705 |
| hemolin expression in the silk glands of galleria mellonella in response to bacterial challenge and prior to cell disintegration. | hemolin, a member of the immunoglobulin protein superfamily, functions in lepidoptera as an opsonin in defence against potential pathogens and seems to play a role in tissue morphogenesis. we show that hemolin gene is expressed in several organs of galleria mellonella larvae, including the nervous system and the silk glands. the expression in the silk glands of the wandering larvae and their isolated abdomens is enhanced within 6h after an injection of bacteria, lipopolysaccharides, or peptidogl ... | 2009 | 19414015 |
| galleria mellonella as an alternative infection model for yersinia pseudotuberculosis. | we report that larvae of the wax moth (galleria mellonella) are susceptible to infection with the human enteropathogen yersinia pseudotuberculosis at 37 degrees c. confocal microscopy demonstrated that in the initial stages of infection the bacteria were taken up into haemocytes. to evaluate the utility of this model for screening y. pseudotuberculosis mutants we constructed and tested a superoxide dismutase c (sodc) mutant. this mutant showed increased susceptibility to superoxide, a key mechan ... | 2009 | 19383703 |
| spite and virulence in the bacterium pseudomonas aeruginosa. | social interactions within populations of pathogenic microbes may play an important role in determining disease virulence. one such ubiquitous interaction is the production of anticompetitor toxins; an example of a spiteful behavior, because it results in direct fitness costs to both the actor and recipient. following from predictions made by mathematical models, we carried out experiments using the bacterium pseudomonas aeruginosa to test under what social conditions toxin (bacteriocin) product ... | 2009 | 19321425 |
| influence of cell density and phase variants of bacterial symbionts (xenorhabdus spp.) on dauer juvenile recovery and development of biocontrol nematodes steinernema carpocapsae and s. feltiae (nematoda: rhabditida). | the rhabditid nematodes steinernema carpocapsae and steinernema feltiae are used in biological control of insect pests. mass production is done in liquid culture media pre-incubated with their bacterial symbionts xenorhabdus nematophila and xenorhabdus bovienii, respectively, before nematode dauer juveniles (djs) are inoculated. as a response to food signals produced by the bacterial symbionts, the djs exit from the developmentally arrested dauer stage (they recover development) and grow to adul ... | 2009 | 19319521 |
| growth and virulence of steinernema glaseri influenced by different subspecies of xenorhabdus nematophilus. | three xenorhabdus nematophilus subspecies influenced steinernema glaseri growth profiles and growth rates, but this was not necessarily because of different bacterial growth rates. virulence of dauer nematodes in larval galleria mellonella varied with the number of dauers retaining bacteria and the bacterial subspecies. virulence was least for dauers grown on x. nematophilus subsp. bovienii because of the lack of retained bacteria. virulence was subsequently restored by culturing these nematodes ... | 1985 | 19294127 |
| comparative genomics and transduction potential of enterococcus faecalis temperate bacteriophages. | to determine the relative importance of temperate bacteriophage in the horizontal gene transfer of fitness and virulence determinants of enterococcus faecalis, a panel of 47 bacteremia isolates were treated with the inducing agents mitomycin c, norfloxacin, and uv radiation. thirty-four phages were purified from culture supernatants and discriminated using pulsed-field gel electrophoresis (pfge) and restriction mapping. from these analyses the genomes of eight representative phages were pyrosequ ... | 2010 | 20008075 |
| genome-wide analysis of dna repeats in burkholderia cenocepacia j2315 identifies a novel adhesin-like gene unique to epidemic-associated strains of the et-12 lineage. | members of the burkholderia cepacia complex (bcc) are respiratory pathogens in patients with cystic fibrosis (cf). close repetitive dna sequences often associate with surface antigens to promote genetic variability in pathogenic bacteria. the genome of burkholderia cenocepacia j2315, a cf isolate belonging to the epidemic lineage edinburgh-toronto (et-12), was analysed for the presence of close repetitive dna sequences. among the 422 dna close repeats, 45 genes potentially involved in virulence ... | 2010 | 20019083 |
| does scavenging extend the host range of entomopathogenic nematodes (nematoda: steinernematidae)? | living and freeze-killed natural and laboratory hosts, with different susceptibility to entomopathogenic nematodes, were exposed to the larvae of steinernema affine and steinernema kraussei in two different experimental arenas (eppendorf tubes, petri dishes), and the success of the colonisation and eventual progeny production were observed. both nematodes were able to colonise both living and dead larvae of galleria mellonella (lepidoptera) and adult blatella germanica (blattodea) even though th ... | 2010 | 20085768 |
| photorhabdus adhesion modification protein (pam) binds extracellular polysaccharide and alters bacterial attachment. | photorhabdus are gram-negative nematode-symbiotic and insect-pathogenic bacteria. the species photorhabdus asymbiotica is able to infect humans as well as insects. we investigated the secreted proteome of a clinical isolate of p. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. | 2010 | 20462430 |
| functional analysis of four processing products from multiple precursors encoded by a lebocin-related gene from manduca sexta. | antimicrobial peptides (amps) are a crucial component of the natural immune system in insects. five types of amps have been identified in the tobacco hornworm manduca sexta, including attacin, cecropin, moricin, gloverin, and lebocin. here we report the isolation of lebocin-related cdna clones and antibacterial activity of their processed protein products. the 17 cdna sequences are composed of a constant 5' end and a variable 3' region containing 3-16 copies of an 81-nucleotide repeat. the seque ... | 2010 | 20096726 |
| role of methionine sulfoxide reductases a and b of enterococcus faecalis in oxidative stress and virulence. | methionine sulfoxide reductases a and b are antioxidant repair enzymes that reduce the s- and r-diastereomers of methionine sulfoxides back to methionine, respectively. enterococcus faecalis, an important nosocomial pathogen, has one msra gene and one msrb gene situated in different parts of the chromosome. promoters have been mapped and mutants have been constructed in two e. faecalis strains (strains jh2-2 and v583) and characterized. for both backgrounds, the mutants are more sensitive than t ... | 2010 | 20566694 |
| identification of an abundant allergen from the sheep louse, bovicola ovis. | infestation of sheep with the louse bovicola ovis is common worldwide and leads to an allergic dermatitis referred to as 'scatter cockle'. ige from an infested lamb was used in immunoaffinity chromatography to purify allergens from crude preparations of whole b. ovis and its faeces. sds-page of the affinity-purified eluates from both preparations showed a dominant band with m(r) of 28.5 kda. spleen cells from a mouse immunised with b. ovis faecal antigens were used to produce hybridomas which we ... | 2010 | 20123101 |
| role of filamentation in galleria mellonella killing by candida albicans. | candida albicans is an important cause of morbidity in hospitalized and immunosuppressed patients. virulence factors of c. albicans include: filamentation, proteinases, adherence proteins and biofilm formation. the objective of this work was to use galleria mellonella as a model to study the roles of c. albicans filamentation in virulence. we focused our study to five genes bcr1, flo8, kem1, suv3 and tec1 that have been shown to play a role in filamentation. filaments are necessary for biofilm f ... | 2010 | 20223293 |
| suitability of different lepidopteran host species for development of bracon hebetor (hymenoptera: braconidae). | bracon hebetor say (hymenoptera: braconidae) is a gregarious larval ectoparasitoid of several species of lepidoptera that are associated with stored products. the suitability of 12 potential lepidopteran host species representing four families was studied in this study for the development and reproduction of b. hebetor. the lepidoptera species used were the indianmeal moth, plodia interpunctella (hübner), mediterranean flour moth, ephestia kuehniella (zeller), almond moth, e. cautella (walker), ... | 2010 | 20388274 |
| biochemical study and in vitro insect immune suppression by a trypsin-like secreted protease from the nematode steinernema carpocapsae. | a trypsin-like serine protease was purified by gel filtration and anion-exchange chromatography from the excretory-secretory products of parasitic phase steinernema carpocapsae. the purified protease exhibited a molecular mass of about 29 kda by sds-page and displayed a pi of 6.3. this protease exhibited high activity with trypsin-specific substrate n-ben-phe-val-arg-p-nitroanilide and was highly sensitive to aprotinin and benzamidine. the purified trypsin protease digested the chromogenic subst ... | 2010 | 20398179 |
| [characterization of proteo-, chitino- and lipolytic enzymes of parasitic fungus conidiobolus coronatus]. | the largest problem in limitation of insect pest population is increasing resistance of them to chemical pesticides. alternative are entomopathogens, which regulate frequency of insect pests. among them decisive role play entomopathogenic fungi, which possess the ability to active penetration through cuticle by mechanical pressure of invasive hypha and production of proteo-, chitino- (egzo- and endochitinases) as well as lipolytic enzymes, which provide nutrients for subsequent development of fu ... | 2010 | 20450015 |
| a pathogenic parasite interferes with phagocytosis of insect immunocompetent cells. | phagocytosis activity of hemocytes of the host galleria mellonella (lepidoptera) was modulated by the infection of the entomopathogenic nematode steinernema feltiae (rahbditida) and was found to be correlated with the opsonization of bacteria by hemolymph factors. the presence of nematodes resulted in a significative decrease in phagocytosis of bacteria by host hemocytes, both in in vivo and in in vitro assays. host interacting proteins (hips), which appear to function as opsonic factors and are ... | 2010 | 20457179 |
| an insect multiligand recognition protein functions as an opsonin for the phagocytosis of microorganisms. | we characterize a novel pathogen recognition protein obtained from the lepidopteran galleria mellonella. this protein recognizes escherichia coli, micrococcus luteus, and candida albicans via specific binding to lipopolysaccharides, lipoteichoic acid, and beta-1,3-glucan, respectively. as a multiligand receptor capable of coping with a broad variety of invading pathogens, it is constitutively produced in the fat body, midgut, and integument but not in the hemocytes and is secreted into the hemol ... | 2010 | 20519517 |
| two novel point mutations in clinical staphylococcus aureus reduce linezolid susceptibility and switch on the stringent response to promote persistent infection. | staphylococcus aureus frequently invades the human bloodstream, leading to life threatening bacteremia and often secondary foci of infection. failure of antibiotic therapy to eradicate infection is frequently described; in some cases associated with altered s. aureus antimicrobial resistance or the small colony variant (scv) phenotype. newer antimicrobials, such as linezolid, remain the last available therapy for some patients with multi-resistant s. aureus infections. using comparative and func ... | 2010 | 20548948 |
| a different repertoire of galleria mellonella antimicrobial peptides in larvae challenged with bacteria and fungi. | to date, functioning of insect humoral immune response is especially well described in diptera. the mechanisms of pathogen recognition, activation of signaling pathways and regulation of antimicrobial defense peptide expression are relatively well known. the present paper demonstrates evidence that the immune system of the lepidoptera moth, galleria mellonella, is also able to distinguish between different classes of microorganisms and responds to the invading pathogen accordingly. g. mellonella ... | 2010 | 20558200 |
| the role of iron uptake in pathogenicity and symbiosis in photorhabdus luminescens tt01. | photorhabdus are gram negative bacteria that are pathogenic to insect larvae whilst also having a mutualistic interaction with nematodes from the family heterorhabditis. iron is an essential nutrient and bacteria have different mechanisms for obtaining both the ferrous (fe2+) and ferric (fe3+) forms of this metal from their environments. in this study we were interested in analyzing the role of fe3+ and fe2+ iron uptake systems in the ability of photorhabdus to interact with its invertebrate hos ... | 2010 | 20569430 |
| zinc and silver glass polyalkenoate cements: an evaluation of their antibacterial nature. | a biofilm is an accumulation of micro-organisms and their extracellular products forming a structured community on a surface. biofilm formation on medical devices has severe health consequences as bacteria growing in this lifestyle are tolerant to both host defence mechanisms and antibiotic therapies. however, silver and zinc ions inhibit the attachment and proliferation of immature biofilms. the objective of this study is to evaluate whether silver and zinc ions eluted from novel glass polyalke ... | 2010 | 20592447 |
| insect-toxic secreted proteins and virulence of the entomopathogenic fungus beauveria bassiana. | fungal virulence has been mostly associated with cuticle-degrading enzymes that can be regulated depending on nutrient conditions. however, few studies have related fungal virulence to insect-toxic secreted proteins. here, we describe how the presence of secreted toxic proteins may be linked to conidial virulence, which can be affected by nutrient factors. in this study we evaluated: (1) the virulence of the conidia of four beauveria bassiana strains (eabb 01/103-su, eabb 01/12-su, eabb 01/88-su ... | 2010 | 20674578 |
| screening of in vivo activated genes in enterococcus faecalis during insect and mouse infections and growth in urine. | enterococcus faecalis is part of the commensal microbiota of humans and its main habitat is the gastrointestinal tract. although harmless in healthy individuals, e. faecalis has emerged as a major cause of nosocomial infections. in order to better understand the transformation of a harmless commensal into a life-threatening pathogen, we developed a recombination-based in vivoexpression technology for e. faecalis. two r-ivet systems with different levels of sensitivity have been constructed in a ... | 2010 | 20686694 |
| molecular pathogenesis of listeria monocytogenes in the alternative model host galleria mellonella. | larvae of galleria mellonella, the greater wax moth, provide an alternative infection model for many human pathogens as they are amenable to use at elevated incubation temperatures (37 °c). this study and a parallel study by mukherjee et al. [mukherjee, k., altincicek, b., hain, t., domann, e., vilcinskas, a. & chakraborty, t. (2010). appl environ microbiol 76, 310-317] establish this insect host as an appropriate model to investigate the pathogenesis of listeria species. in this study we ... | 2010 | 20688820 |
| [study of peptide content of antibacterial fractions by liquid chromatography and mass spectrometry]. | the fractions containing antimicrobic peptides have been purified from a haemolymph of caterpillars galleria mellonella by chromatographic methods and studied by mass spectrometry. | 2010 | 20695218 |
| structure of penaeus stylirostris densovirus, a shrimp pathogen. | penaeus stylirostris densovirus (pstdnv), a pathogen of penaeid shrimp, causes significant damage to farmed and wild shrimp populations. in contrast to other parvoviruses, pstdnv probably has only one type of capsid protein that lacks the phospholipase a2 activity that has been implicated as a requirement during parvoviral host cell infection. the structure of recombinant virus-like particles, composed of 60 copies of the 37.5-kda coat protein, the smallest parvoviral capsid protein reported thu ... | 2010 | 20702621 |
| eicosanoids mediate hemolymph oxidative and antioxidative response in larvae of galleria mellonella l. | antioxidant enzymes play a major role in the defense against pro-oxidative effects of xenobiotics and pro-oxidant plant allelochemicals in insects. we posed the hypothesis that eicosanoids also mediate antioxidant enzymatic defense reactions to pro-oxidant challenge. to test this idea, we reared first-instar larvae of galleria mellonella (l.) with the lypoxygenase inhibitor, esculetin (0.001%), the phospholipase a(2) inhibitor, dexamethasone (0.001%) and the dual inhibitor of cyclooxygenase and ... | 2010 | 20138233 |
| study of peptide fractions from hemolymph of galleria mellonella. | changes in the peptide composition of hemolymph of galleria mellonella larvae induced by their immunization have been studied, and some new peptides have been found. the composition of fractions exhibiting antibacterial activity was investigated. known antibacterial peptides have been found in the hemolymph of control larvae and those immunized with bacteria. | 2010 | 21077837 |
| characterization of kunitz-type protease inhibitor purified from hemolymph of galleria mellonella larvae. | we characterized a kunitz-type protease inhibitor (gm ktpi) obtained from the hemolymph of galleria mellonella larvae immunized with escherichia coli. the structural analysis of the cloned cdna showed that it consists of 56 residues derived from the precursor of 75 amino acids. the peptide was constitutively produced in the fat bodies, but not in the midgut nor the integument of larvae. in our analysis of stage-dependent expression, its transcript was detected within the midgut, the fat bodies a ... | 2010 | 20826210 |
| comparison of the regulation, metabolic functions, and roles in virulence of the glyceraldehyde-3-phosphate dehydrogenase homologues gapa and gapb in staphylococcus aureus. | the gram-positive bacterium staphylococcus aureus contains two glyceraldehyde-3-phosphate dehydrogenase (gapdh) homologues known as gapa and gapb. gapa has been characterized as a functional gapdh protein, but currently there is no biological evidence for the role of gapb in metabolism in s. aureus. in this study we show through a number of complementary methods that s. aureus gapa is essential for glycolysis while gapb is essential in gluconeogenesis. these proteins are reciprocally regulated i ... | 2010 | 20876289 |
| caspofungin primes the immune response of the larvae of galleria mellonella and induces a non-specific antimicrobial response. | the echinocandins (e.g. caspofungin) function by inhibiting the synthesis of 1,3-β-glucan in the fungal cell wall. while the potent antifungal activity of caspofungin has been well characterized in mammals, this study investigated the in vivo antifungal effect of caspofungin using larvae of the insect galleria mellonella. caspofungin was successful in increasing the survival of larvae that were inoculated with candida albicans 1 h before the drug was administered, particularly when a conc ... | 2010 | 20947665 |
| pathogenicity of aspergillus fumigatus mutants assessed in galleria mellonella matches that in mice. | aspergillus fumigatus is a clinically important fungus with the ability to cause invasive aspergillosis with high mortality rates in immunocompromised patients and chronic pulmonary aspergillosis in immunocompetent individuals. virulence of mutants has traditionally been assessed using mammalian hosts such as mice and rats and more recently the fruit fly, drosophila melanogaster, demonstrated the potential to act as an in vivo host suitable for screening aspergillus mutants. in this study using ... | 2010 | 20950221 |
| stenotrophomonas maltophilia strains from cystic fibrosis patients: genomic variability and molecular characterization of some virulence determinants. | the genetic relatedness of 52 stenotrophomonas maltophilia strains, collected from various environmental and clinical sources, including cystic fibrosis (cf) patients, as well as the presence and the expression of some virulence-associated genes were studied. pulsed-field gel electrophoresis (pfge) analysis identified 47 profiles and three clusters of isolates with an identical pfge pattern considered to be indistinguishable strains. restriction fragment length polymorphism of the gyrb gene grou ... | 2010 | 20952251 |
| clpb, a class iii heat-shock gene regulated by ctsr, is involved in thermotolerance and virulence of enterococcus faecalis. | here, we transcriptionally and phenotypically characterized the clpb gene from enterococcus faecalis. northern blot analysis identified a monocistronic mrna strongly induced at 48 and 50 °c. in silico analysis identified that the clpb gene encodes a protein of 868 aa with a predicted molecular mass of approximately 98 kda, presenting two conserved atp-binding domains. sequence analysis also identified a ctsr-binding box upstream of the putative -10 sequence, and inactivation of the ctsr gene res ... | 2010 | 21148206 |
| susceptibility of north-american and european crickets to acheta domesticus densovirus (addnv) and associated epizootics. | the european house cricket, acheta domesticus l., is highly susceptible to a. domesticus densovirus (addnv). commercial rearings of crickets in europe are frequently decimated by this pathogen. mortality was predominant in the last larval stage and young adults. infected a. domesticus were smaller, less active, did not jump as high, and the adult females seldom lived more than 10-14 days. the most obvious pathological change was the completely empty digestive caecae. infected tissues included ad ... | 2010 | 21167171 |
| involvement of apolipophorin iii in antibacterial defense of galleria mellonella larvae. | apolipophorin iii (apolp-iii) is an abundant hemolymph protein involved in lipid transport and immune response in insects. we investigated involvement of apolp-iii in the antibacterial response in galleria mellonella larvae. immune challenge with gram-negative (escherichia coli, klebsiella pneumoniae) and gram-positive (micrococcus luteus) bacteria led to an increase in the level of apolp-iii in g. mellonella hemolymph, 0.5-2h and 8h after treatment, respectively. apolp-iii purified from larval ... | 2010 | 20959145 |
| using an insect model to assess correlation between temperature and virulence in bacillus weihenstephanensis and bacillus cereus. | the closely related bacterial species bacillus cereus and bacillus weihenstephanensis are adapted to the mesophilic and the psychrotrophic temperature range, respectively. while b. cereus strains are associated with foodborne diseases, b. weihenstephanensis strains are so far not, although similar virulence genes are found in both species. our investigations show that both species were virulent in the insect model, galleria mellonella, following infection via oral and haemocoel routes. however, ... | 2011 | 21276046 |
| proteolytic enzyme production by strains of the insect pathogen xenorhabdus and characterization of an early-log-phase-secreted protease as a potential virulence factor. | as a comparison to a similar study on photorhabdus strains, 15 xenorhabdus bacterial strains and secondary phenotypic variants of two strains were screened for proteolytic activity by five detection methods. although the number and intensity of proteolytic activities were different, every strain was positive for proteolytic activity by several tests. zymography following native page detected two groups of activities with different substrate affinities and a higher and lower electrophoretic mobil ... | 2010 | 20802071 |
| virulence in an insect model differs between mating types in aspergillus fumigatus. | aspergillus fumigatus is an opportunistic fungal pathogen that has recently been found to undergo sexual reproduction. previous work suggested that invasiveness differs between mating types, and in the present study we tested whether virulence differs between mating types in an in vivo model, i.e., larvae of the wax moth galleria mellonella. we measured virulence of 20 a. fumigatus isolates; three mat1-1 isolates of environmental origin, five mat1-1 isolates of clinical origin, seven mat1-2 isol ... | 2011 | 20818921 |
| aspergillus fumigatus acum regulates both iron acquisition and gluconeogenesis. | relatively few transcription factors that govern the virulence of aspergillus fumigatus are known. we constructed 11 a. fumigatus transcription factor mutants and screened them for altered virulence in galleria mellonella larvae. we discovered that the zinc cluster transcription factor, acum, is essential for maximal virulence in this model, as well as in murine models of haematogenously disseminated and invasive pulmonary aspergillosis. transcriptional profiling experiments suggested that acum ... | 2010 | 21062375 |
| the collagen-binding protein cnm is required for streptococcus mutans adherence to and intracellular invasion of human coronary artery endothelial cells. | streptococcus mutans is considered the primary etiologic agent of dental caries, a global health problem that affects 60 to 90% of the population, and a leading causative agent of infective endocarditis. it can be divided into four different serotypes (c, e, f, and k), with serotype c strains being the most common in the oral cavity. in this study, we demonstrate that in addition to omz175 and b14, three other strains (nctc11060, lm7, and om50e) of the less prevalent serotypes e and f are able t ... | 2011 | 21422186 |
| quorum sensing inhibitors increase the susceptibility of bacterial biofilms to antibiotics in vitro and in vivo. | although the exact role of quorum sensing (qs) in various stages of biofilm formation, maturation, and dispersal and in biofilm resistance is not entirely clear, the use of qs inhibitors (qsi) has been proposed as a potential antibiofilm strategy. we have investigated whether qsi enhance the susceptibility of bacterial biofilms to treatment with conventional antimicrobial agents. the qsi used in our study target the acyl-homoserine lactone-based qs system present in pseudomonas aeruginosa and bu ... | 2011 | 21422204 |
| myogenic nature of insect heartbeat and intestinal peristalsis, revealed by neuromuscular paralysis caused by the sting of a braconid wasp. | larvae of the greater waxmoth (galleria mellonella) become paralysed by the venom of the braconid wasp (habrobracon hebetor) a few minutes after intoxication. the profound neuromuscular paralysis, which may last for several weeks, includes all somatic muscles that are innervated through neuromuscular transmission. the peristaltic contractions of the heart and intestine, which are regulated by the depolarisation potentials of the myocardium or intestinal epithelial muscles, remain unaffected and ... | 2010 | 21093450 |