| biolistic co-transformation of metarhizium anisopliae var. acridum strain cg423 with green fluorescent protein and resistance to glufosinate ammonium. | metarhizium anisopliae var. acridum (syn. m. flavoviride) is recognized as a highly specific and virulent mycopathogen of locusts and grasshoppers and is currently being developed as a biological control agent for this group of insects in brazil. intact conidia of m. anisopliae var. acridum strain cg423 were transformed using microparticle bombardment. plasmids used were: (1) pbarks1 carrying the bar gene of streptomyces hygroscopicus fused to the aspergillus nidulans trpc promoter, encoding res ... | 2000 | 11024271 |
| igs sequence variation, group-i introns and the complete nuclear ribosomal dna of the entomopathogenic fungus metarhizium: excellent tools for isolate detection and phylogenetic analysis. | the complete nuclear rdna gene complex of metarhizium anisopliae var. anisopliae isolate me1 is 8118bp long and contains the 18s, 5.8s, and 28s rrna genes as well as the its and igs regions. variation in the its of isolates of m. anisopliae var. anisopliae and one each of metarhizium anisopliae var. acridum, metarhizium flavoviride var. flavoviride, and metarhizium flavoviride var. minus, clustered 39 out of 40 of m. anisopliae var. anisopliae isolates in one clade. nucleotide sequence variation ... | 2003 | 12620253 |
| developmental and transcriptional responses to host and nonhost cuticles by the specific locust pathogen metarhizium anisopliae var. acridum. | transcript patterns elicited in response to hosts can reveal how fungi recognize suitable hosts and the mechanisms involved in pathogenicity. these patterns could be fashioned by recognition of host-specific topographical features or by chemical components displayed or released by the host. we investigated this in the specific locust pathogen metarhizium anisopliae var. acridum. only host (schistocerca gregaria) cuticle stimulated the full developmental program of germination and differentiation ... | 2005 | 15879528 |
| development of a simple and rapid agrobacterium tumefaciens-mediated transformation system for the entomopathogenic fungus metarhizium anisopliae var. acridum. | to examine the ability of agrobacterium to attach to metarhizium anisopliae var. acridum strain cg423 under co-cultivation and to develop an agrobacterium-mediated method of gene delivery into strain cg423, a promising agent for biological control of grasshoppers. | 2007 | 17309500 |
| real-time quantitative pcr for analysis of candidate fungal biopesticides against malaria: technique validation and first applications. | recent research has indicated that fungal biopesticides could augment existing malaria vector control tools. here we present a set of methodologies to monitor the in vivo kinetics of entomopathogenic fungi in anopheles in the presence or absence of malaria parasites using quantitative real-time pcr. three qpcr assays were successfully developed for counting fungal genomes: "specific" assays capable of distinguishing two well characterized fungal entomopathogens beauveria bassiana isolate imi3915 ... | 2009 | 19320043 |
| crowded locusts produce hatchlings vulnerable to fungal attack. | transgenerational effects of parental experience on offspring immunity are well documented in the vertebrate literature (where antibodies play an obligatory role), but have only recently been described in invertebrates. we have assessed the impact of parental rearing density upon offspring disease resistance by challenging day-old locust hatchlings (schistocerca gregaria) from either crowd- or solitary-reared parents with the fungal pathogen metarhizium anisopliae var. acridum. when immersed in ... | 2009 | 19675004 |
| characterization of metarhizium species and varieties based on molecular analysis, heat tolerance and cold activity. | the genetic relationships and conidial tolerances to high and low temperatures were determined for isolates of several metarhizium species and varieties. | 2010 | 19664068 |
| lack of pathogenicity and toxicity of the mycoinsecticide metarhizium anisopliae var. acridum following acute gastric exposure in mice. | metarhizium anisopliae var. acridum, monospore culture eh-502/8 (cnrcb mapl40), isolated in mexico from schistocerca piceifrons ssp. piceifrons (orthoptera: acrididae) was tested for acute oral intragastric pathogenicity and toxicity in cd-1 mice. animals were inoculated with one dose (10(8) conidia/animal) of viable (72 mice), non-viable (24 mice) conidia and compared to 18 control mice. clinical observations were done daily; mycological and histological tests were performed during necropsies a ... | 2009 | 19535139 |
| thermotolerance of germlings and mycelium of the insect-pathogenic fungus metarhizium spp. and mycelial recovery after heat stress. | the upper temperature limits for germination and growth were determined for metarhizium acridum (arsef 324, 3341 and 3609), m. robertsii (arsef 2575), m. anisopliae (arsef 5749), and aspergillus nidulans (atcc 10074). most of the metarhizium species germinated well at 35 and 36 degrees c; however, compared to 28 degrees c, the growth was very slow (except arsef 5749 from mexico, which germinated at 35 degrees c, but did not grow at 34 or 36 degrees c). germination was severely impaired at 38 and ... | 2010 | 20586069 |
| quantification of cyclobutane pyrimidine dimers induced by uvb radiation in conidia of the fungi aspergillus fumigatus, aspergillus nidulans, metarhizium acridum and metarhizium robertsii. | conidia are responsible for reproduction, dispersal, environmental persistence and host infection of many fungal species. one of the main environmental factors that can kill and/or damage conidia is solar uv radiation. cyclobutane pyrimidine dimers (cpd) are the major dna photoproducts induced by uvb. we examined the conidial germination kinetics and the occurrence of cpd in dna of conidia exposed to different doses of uvb radiation. conidia of aspergillus fumigatus, aspergillus nidulans and met ... | 2010 | 20860693 |
| construction and analysis of a normalized cdna library from metarhizium anisopliae var. acridum germinating and differentiating on locusta migratoria wings. | a cdna library construction method was established that allows gene expression of the entomopathogenic fungus metarhizium anisopliae var. acridum to be studied during its growth on locusta migratoria wings. before inoculation, locust wings were treated with an rna fragmentation buffer to degrade host nucleic acid. reverse transcription-pcr analysis of several constitutively expressed locust genes was used to confirm the degradation of locust nucleic acid. a normalized cdna library of m. anisopli ... | 2009 | 19076228 |
| characterization of a novel fungal chitosanase csn2 from gongronella sp. jg. | a 28kda chitosanase designated as csn2 was purified from the culture broth of the fungus gongronella sp. jg through three chromatography steps: cm-sepharose ff, superdex 200 and sp-sepharose ff. its optimal reaction ph and temperature were ph 5.6 and between 55 degrees c and 60 degrees c. the half-lives of csn2 at 50 degrees c and 55 degrees c were estimated to be 30min and 11min, respectively. the k(m) value of csn2 in sodium acetate buffer (ph 5.6) at 55 degrees c was 8.86mg/ml. mn(2+), ca(2+) ... | 2008 | 18722595 |
| interaction between paranosema locustae and metarhizium anisopliae var. acridum, two pathogens of the desert locust, schistocerca gregaria under laboratory conditions. | the interaction between two pathogens, the microsporidian paranosema locustae canning and the fungus metarhizium anisopliae var. acridum driver and milner was studied under laboratory conditions in an attempt to develop an improved method of microbial control for the desert locust, schistocerca gregaria forskål. fifth-instar locust nymphs, reared in the laboratory, were treated with various concentrations of one of the two pathogens or with both pathogens. the numbers of locusts killed were reco ... | 2008 | 18005982 |
| the contribution of surface waxes to pre-penetration growth of an entomopathogenic fungus on host cuticle. | a locust wing bioassay, that allowed an entomopathogenic fungus to be removed from host cuticle before penetration, was used to investigate the role of surface lipids and waxes in pre-penetration growth of the specific locust pathogen metarhizium anisopliae var. acridum. sem and atomic force electron microscopy showed the impact of the fungus on the architecture of the cuticle surface. although the fungus can germinate on authentic alkanes as the sole carbon source, only low levels of germinatio ... | 2007 | 17324760 |
| immune responses of locusts to challenge with the pathogenic fungus metarhizium or high doses of laminarin. | two isolates of metarhizium anisopliae var acridum were tested for their effects on the locust immune system and for comparison with the effects of challenge by injection with laminarin. isolate imi 330189 (referred to hereafter as met 189) is highly pathogenic whether applied topically as conidia or injected as blastospores. however, isolate arsef 728 (referred to hereafter as met 728) is pathogenic only when injected as blastospores, suggesting that the lack of pathogenicity of topically appli ... | 2006 | 16413931 |
| development of a pcr-based diagnostic assay for the specific detection of the entomopathogenic fungus metarhizium anisopliae var. acridum. | the entomopathogenic fungus metarhizium anisopliae var. acridum is registered as a mycopesticide for acridid control in africa and australia. traditionally, identification of m. anisopliae var. acridum infection in grasshoppers and locusts has relied upon development of fungal growth in infected cadavers. conventional methods of detection of this entomopathogen in the environment and non-target organisms have been based on culture and bioassay. a pcr-based method for the detection of m. anisopli ... | 2005 | 16279424 |
| reduction in host-finding behaviour in fungus-infected mosquitoes is correlated with reduction in olfactory receptor neuron responsiveness. | abstract: background: chemical insecticides against mosquitoes are a major component of malaria control worldwide. fungal entomopathogens formulated as biopesticides and applied as insecticide residual sprays could augment current control strategies and mitigate the evolution of resistance to chemical-based insecticides. methods: anopheles stephensi mosquitoes were exposed to beauveria bassiana or metarhizium acridum fungal spores and sub-lethal effects of exposure to fungal infection were studi ... | 2011 | 21812944 |
| influence of growth environment on tolerance to uv-b radiation, germination speed, and morphology of metarhizium anisopliae var. acridum conidia. | we previously reported wide variability in uv-b tolerance among different metarhizium anisopliae isolates [braga, g.u.l., flint, s.d., miller, c.d., anderson, a.j., roberts, d.w., 2001a. variability in response to uv-b among species and strains of metarhizium isolated from sites at latitudes from 61 degrees n to 54 degrees s. j. invertebr. pathol. 78, 98-108] as well as wide phenotypic variability in some of these isolates in response to alterations in their growth environments [rangel, d.e.n., ... | 2005 | 16005467 |
| effects of double-stranded rna in metarhizium anisopliae var. acridum and paecilomyces fumosoroseus on protease activities, conidia production, and virulence. | isogenic strains (with and without dsrna) of the entomogenous fungi metarhizium anisopliae var. acridum and paecilomyces fumosoroseus were investigated for correlation between the presence of dsrna and the production of cuticle-degrading proteases that play an important role in host parasitism, total secreted protein, and conidia production. similar levels of cuticle-degrading subtilisin-like (pr1) protease were observed for isogenic strains of m. anisopliae var. acridum after growth in medium s ... | 2004 | 15213741 |
| production and processing of metarhizium anisopliae var. acridum submerged conidia for locust and grasshopper control. | currently, mycopesticide development for locust and grasshopper control depends on aerial conidia or submerged spores of entomopathogenic fungi. in our study, the production of submerged conidia of metarhizium anisopliae var. acridum (imi 330189) was investigated in a liquid medium containing 3% biomalt and 1% yeast extract (bh-medium). the effects of freeze and spray drying techniques on the quality of submerged conidia were determined. the influence of different additives on the viability of f ... | 2004 | 15035510 |
| behavioral thermoregulation in the migratory locust: a therapy to overcome fungal infection. | we examined under laboratory conditions the thermopreference of the migratory locust, locusta migratoria migratorioides, following infection by the entomopathogenic fungus metarhizium anisopliae var. acridum and its influence on mycosis. infected locusts raised their body temperature more frequently than healthy conspecifics through selection of high temperatures in a heat gradient. thermoregulation did not, however, alter the frequency of feeding events nor the amount of food eaten by infected ... | 2004 | 14614620 |
| toxicity and pathogenicity of metarhizium anisopliae var. acridum (deuteromycotina, hyphomycetes) and fipronil to the fringe-toed lizard acanthodactylus dumerili (squamata: lacertidae). | reptiles in arid and semiarid zones are frequently exposed to insecticides sprayed to control locusts and grasshoppers. we evaluated the toxicity and pathogenicity of new biological and chemical control agents to the fringe-toed lizard acanthodactylus dumerili in mauritania, west africa. a mycoinsecticide based on spores of the entomopathogenic fungus metarhizium anisopliae var. acridum (isolate imi 330189, green muscle) was tested at high challenge concentrations, using three exposure routes. t ... | 2003 | 12836967 |
| A strong promoter, PMagpd, provides a tool for high gene expression in entomopathogenic fungus, Metarhizium acridum. | A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter (PMagpd) was obtained from Metarhizium acridum and its active region analyzed by 5'-deletion strategy using ß-glucuronidase (GUS) as a reporter. Sequence analysis revealed that typical regulatory elements of PMagpd were included in the 1.7 kb region upstream of the start codon of the Magpd gene. Deletion of the region from -1,691 bp to -1,463 bp, where the gpd box is harbored, did not significantly affect the PMagpd activity. Deletio ... | 2011 | 22109936 |
| the immune response of the desert locust schistocerca gregaria during mycosis of the entomopathogenic fungus, metarhizium anisopliae var acridum. | topical application of metarhizium anisopliae var acridum to the desert locust schistocerca gregaria resulted in changes in the biochemistry and antimicrobial defenses of the haemolymph. m. anisopliae var acridum colonized the host haemolymph from day two post application. the haemocytes did not attach to, phagocytose or nodulate elements of the fungus. however, the presence of the fungus appeared to stimulate hemocyte aggregation over the first few days of mycosis though the number of aggregate ... | 2000 | 12770206 |
| comparative transcriptomic analysis of immune responses of the migratory locust, locusta migratoria, to challenge by the fungal insect pathogen, metarhizium acridum. | the migratory locust, locusta migratoria manilensis, is an immensely destructive agricultural pest that forms a devastating and voracious gregarious phase. the fungal insect pathogen, metarhizium acridum, is a specialized locust pathogen that has been used as a potent mycoinsecticide for locust control. little, however, is known about locust immune tissue, i.e. fat body and hemocyte, responses to challenge by this fungus. | 2015 | 26503342 |
| evaluating the lethal and pre-lethal effects of a range of fungi against adult anopheles stephensi mosquitoes. | insecticide resistance is seriously undermining efforts to eliminate malaria. in response, research on alternatives to the use of chemical insecticides against adult mosquito vectors has been increasing. fungal entomopathogens formulated as biopesticides have received much attention and have shown considerable potential. this research has necessarily focused on relatively few fungal isolates in order to 'prove concept'. further, most attention has been paid to examining fungal virulence (lethali ... | 2012 | 23126549 |
| inhibition of fungal growth in thermoregulating locusts, locusta migratoria, infected by the fungus metarhizium anisopliae var acridum. | the locust, locusta migratoria, has the capacity to develop a behavioural fever which reduces fungal infection by metarhizium anisopliae var acridum. we investigated hemocyte and blastospore kinetics in infected insects under conditions that did or did not allow thermoregulation. hemocyte concentrations were severely reduced in inoculated insects that did not thermoregulate but remained similar to those of controls in inoculated insects that were allowed to thermoregulate. reductions in hemocyte ... | 2003 | 12623310 |
| assessment of health and growth of ring-necked pheasants following consumption of infected insects or conidia of entomopathogenic fungi, metarhizium anisopliae var. acridum and beauveria bassiana, from madagascar and north america. | isolates of two fungi (beauveria bassiana and metarhizium anisopliae var. acridum) from madagascar are being developed for control of grasshoppers and locusts, as part of a search for alternatives to environmentally detrimental chemical insecticides. the probable effects of these entomopathogens on nontarget species must be determined before operational use. birds may become exposed to these fungi either directly, by consuming spores deposited on their food items, or secondarily, by consuming gr ... | 2002 | 12515592 |
| attenuation of fungal infection in thermoregulating locusta migratoria is accompanied by changes in hemolymph proteins. | hemolymph proteins in the locust, locusta migratoria migratorioides infected with the fungus metarhizium anisopliae var acridum were analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). under conditions that allowed locusts to thermoregulate, 2 proteins, itb1 (ca. 18kda) and itb2 (ca. 13kda) were induced 48h post inoculation. in contrast, under non-thermoregulating conditions, only 1 band, intb1 (ca. 18kda) was induced with similar molecular mass to itb1. itb1 and ... | 2002 | 12417209 |
| host-pathogen interactions in a varying environment: temperature, behavioural fever and fitness. | we demonstrate how variable temperatures, mediated by host thermoregulation and behavioural fever, critically affect the interaction between a host (the desert locust, schistocerca gregaria) and a pathogen (the fungus metarhizium anisopliae var. acridum). by means of behavioural thermoregulation, infected locusts can raise their body temperatures to fever levels. the adaptive value of this behaviour was examined using three thermal regimes wherein maximum body temperatures achievable were: (i) b ... | 2002 | 12184830 |
| risks to the aquatic ecosystem from the application of metarhizium anisopliae for locust control in australia. | laboratory tests of metarhizium anisopliae var acridum driver & milner, at a dose of 1.3 x 10(6) conidia ml-1, had no adverse effects on nymphs of mayfly, ulmerophlebia sp or 8-week-old fry of the rainbow fish, melanotaenia duboulayi castelnau. this dose was toxic to the cladoceran, ceriodaphnia dubia richard, causing 100% mortality in 48 h. when this test was repeated at doses of up to 6.7 x 10(3) conidia ml-1, there was only 5% mortality after 192 h. spraying of artificial water sources with a ... | 2002 | 12146174 |
| coping with crowds: density-dependent disease resistance in desert locusts. | parasite transmission generally exhibits some form of positive density dependence. thus, as population density increases, so too does the per capita risk of becoming infected. under such circumstances, natural selection should favor individuals that use cues associated with population density to determine the optimal allocation of resources to disease resistance mechanisms. as a consequence, individuals experiencing crowded conditions are predicted to be more resistant to parasites and pathogens ... | 2002 | 11960003 |
| effects of temperature and relative humidity on sporulation of metarhizium anisopliae var. acridum in mycosed cadavers of schistocerca gregaria. | the effects of relative humidity (rh) and temperature on the sporulation of metarhizium anisopliae var. acridum on mycosed cadavers of desert locust, schistocerca gregaria, were assessed in the laboratory. quantitative assessments of conidial production over 10 days under constant conditions showed that sporulation was optimized at rh > 96% and at temperatures between 20 and 30 degrees c. under both these conditions >10(9) conidia/cadaver were produced. at 25 degrees c, conidial yield was maximi ... | 2001 | 11812107 |
| adult survival, maturation, and reproduction of the desert locust schistocerca gregaria infected with the fungus metarhizium anisopliae var acridum. | studies were conducted with two different doses of metarhizium anisopliae var acridum to examine the effects on survival and reproductive potential of adult schistocerca gregaria under conditions that either limited thermoregulation or enabled optimal thermoregulation. adult s. gregaria infected with the fungal pathogen showed either a rapid and high mortality at relatively constant temperatures or a much reduced mortality and lengthened survival time when allowed to thermoregulate. mortality ra ... | 2001 | 11500087 |
| aerial treatment of the australian plague locust, chortoicetes terminifera (orthoptera: acrididae) with metarhizium anisopliae (deuteromycotina: hyphomycetes). | between october 1999 and april 2000, nearly 4000 ha of nymphal bands and adult swarms of chortoicetes terminifera (walker) were aerially treated using a ulv oil formulation of strain fi-985 of metarhizium anisopliae var. acridum. during the mild weather (maxima 22-30 degrees c) of spring (october), there was little change in nymphal bands during the first week but at all doses between 25-100 g (1-4 x 10(12) conidia) ha(-1), the bands rapidly declined 9-12 days after treatment reaching > 90% mort ... | 2001 | 11260723 |
| acute toxicity of locust insecticides to two indigenous invertebrates from sahelian temporary ponds. | during desert locust plagues large amounts of insecticides are used for control operations. drift from these treatments and accidental overspraying may contaminate small surface waters such as temporary ponds. the present study describes methods for static acute toxicity tests with two abundant organisms that occur in temporary ponds in the african sahel region: the fairy shrimp streptocephalus sudanicus daday (branchiopoda, anostraca, streptocephalidae) and the backswimmer anisops sardeus herri ... | 2001 | 11161680 |
| the effects of the fungus metarhizium anisopliae var. acridum on different stages of lutzomyia longipalpis (diptera: psychodidae). | the control of visceral leishmaniasis (vl) vector is often based on the application of chemical residual insecticide. however, this strategy has not been effective. the continuing search for an appropriate vector control may include the use of biological control. this study evaluates the effects of the fungus metarhizium anisopliae var. acridum on lutzomyia longipalpis. five concentrations of the fungus were utilized, 1 x 10(4) to 1 x 10(8) conidia/ml, accompanied by controls. the unhatched eggs ... | 2010 | 19883621 |
| construction and preliminary analysis of a normalized cdna library from locusta migratoria manilensis topically infected with metarhizium anisopliae var. acridum. | the insect immune response to fungal infection is poorly understood at the molecular level. to explore the molecular basis of this process, a novel method to analyze the gene transcripts of insects in response to pathogenic fungus was established. a normalized cdna library based on the smart method combined with dsn (duplex-specific nuclease) treatment was constructed using mrna extracted from the fat body and hemocytes of locusta migratoria manilensis 6-24h after being topically infected with m ... | 2010 | 20470782 |
| interactions of two insect pathogens, paranosema locustae (protista: microsporidia) and metarhizium acridum (fungi: hypocreales), during a mixed infection of locusta migratoria (insecta: orthoptera) nymphs. | locusta migratoria nymphs were fed paranosema locustae spores and/or surface-treated with metarhizium acridum 3 (assay 1), 6 (assay 2) or 9 days (assay 3) post microsporidia application (p.m.a.). these three dates corresponded to the key phases of p. locustae development: (a) mass proliferation, (b) transition to sporogenesis and (c) onset of spore maturation, respectively. as a result, locust mortality due to mixed treatment increased slower, equally and faster, as compared to mortality expecte ... | 2010 | 20932843 |
| a proteomic approach to identifying proteins differentially expressed in conidia and mycelium of the entomopathogenic fungus metarhizium acridum. | metarhizium spp. is an important worldwide group of entomopathogenic fungi used as an interesting alternative to chemical insecticides in programs of agricultural pest and disease vector control. metarhizium conidia are important in fungal propagation and also are responsible for host infection. despite their importance, several aspects of conidial biology, including their proteome, are still unknown. we have established conidial and mycelial proteome reference maps for metarhizium acridum using ... | 2010 | 20943168 |
| the rhizosphere-competent entomopathogen metarhizium anisopliae expresses a specific subset of genes in plant root exudate. | metarhizium anisopliae and beauveria bassiana are ubiquitous insect pathogens and possible plant symbionts, as some strains are endophytic or colonize the rhizosphere. we evaluated 11 strains of m. anisopliae and b. bassiana, and two soil saprophytes (the non-rhizospheric aspergillus niger and the rhizosphere-competent trichoderma harzianum) for their ability to germinate in bean root exudates (res). our results showed that some generalist strains of m. anisopliae were as good at germinating in ... | 2010 | 20947574 |
| genetically altering the expression of neutral trehalase gene affects conidiospore thermotolerance of the entomopathogenic fungus metarhizium acridum. | the entomopathogenic fungus metarhizium acridum has been used as an important biocontrol agent instead of insecticides for controlling crop pests throughout the world. however, its virulence varies with environmental factors, especially temperature. neutral trehalase (ntl) hydrolyzes trehalose, which plays a role in environmental stress response in many organisms, including m. acridum. demonstration of a relationship between ntl and thermotolerance or virulence may offer a new strategy for enhan ... | 2011 | 21310069 |
| mafks, a β-1,3-glucan synthase, is involved in cell wall integrity, hyperosmotic pressure tolerance and conidiation in metarhizium acridum. | β-glucan is an essential cell wall structural component in most fungi and its helical structure is important for maintenance of cell wall elasticity in fungi. the gene encoding β-1,3-glucan synthase in the entomopathogenic fungus metarhizium acridum (mafks; hq441252) was cloned. the function of mafks was analyzed by rna interference (rnai). fks-rnai transformants were more sensitive to agents that disturb the cell wall or cell membrane and to hyperosmotic stress than the wild type. in comparison ... | 2011 | 21562714 |
| downregulation of pre-rrna processing gene mamrd1 decreases growth, conidiation and virulence in the entomopathogenic fungus metarhizium acridum. | mrd1 is one of the trans-acting proteins and plays an important role in precursor ribosomal rna processing. here we characterized the mamrd1 gene from metarhizium acridum and studied its function in growth, conidiation and virulence using rna interference. the mamrd1 gene was identified as participating in the processing of pre-rrna in m. acridum and was highly upregulated during the infection process. a mamrd1-rnai strain exhibited an appearance of fluffy mycelia, a defective branching pattern ... | 2011 | 21624460 |
| mapmi gene contributes to stress tolerance and virulence of the entomopathogenic fungus, metarhizium acridum. | phosphomannose isomerase (pmi) catalyzes the reversible interconversion of fructose 6-phosphate (fru-6-p) and mannose 6-phosphate (man-6-p), providing a link between glycolysis and the mannose metabolic pathway. in this study, we identified pmi gene (mapmi) from the entomopathogenic fungus, metarhizium acridum, and analyzed its functions using rna interference (rnai). amending the growth medium with cell stress chemicals significantly reduced growth, conidial production and percent germination i ... | 2011 | 21683706 |
| insertion of an esterase gene into a specific locust pathogen (metarhizium acridum) enables it to infect caterpillars. | an enduring theme in pathogenic microbiology is poor understanding of the mechanisms of host specificity. metarhizium is a cosmopolitan genus of invertebrate pathogens that contains generalist species with broad host ranges such as m. robertsii (formerly known as m. anisopliae var. anisopliae) as well as specialists such as the acridid-specific grasshopper pathogen m. acridum. during growth on caterpillar (manduca sexta) cuticle, m. robertsii up-regulates a gene (mest1) that is absent in m. acri ... | 2011 | 21731492 |
| locusts increase carbohydrate consumption to protect against a fungal biopesticide. | there is growing evidence to suggest that hosts can alter their dietary intake to recoup the specific resources involved in mounting effective resistance against parasites and pathogens. we examined macronutrient ingestion and disease-resistance in the australian plague locust (chortoicetes terminifera), challenged with a fungal pathogen (metarhizium acridum) under dietary regimes varying in their relative amounts of protein and digestible carbohydrate. dietary protein influenced constitutive im ... | 2014 | 24862155 |
| The inhibitory effect of the fungal toxin, destruxin A, on behavioural fever in the desert locust. | During an infection locusts behaviourally fever by seeking out higher environmental temperatures. This behaviour places the pathogen at sub-optimal growth temperatures while improving the efficiency of the immune system, thereby prolonging the lifespan of the host. It is therefore in the interest of the pathogen to either adapt to fever-like temperatures or to evolve mechanisms to interfere with, or inhibit fever. We investigated the behavioural fever response of desert locusts to two fungal pat ... | 2011 | 21729702 |
| ontogenetic changes in immunity and susceptibility to fungal infection in mormon crickets anabrus simplex. | insects have innate immunity that may be weakened by resource allocation to growth. i measured enzymatic immunity, encapsulation response, and susceptibility to fungal infection in mormon crickets of known age. although the concentrations of circulating spontaneous and total phenoloxidase (po) increased with age from the most recent molt in late instar nymphs (5th, 6th, and 7th) and 0-5day old adults, mean values did not differ between stadia, indicating that circulating po titers are knocked ba ... | 2011 | 22206886 |
| ß-1,3-Glucan recognition protein (ßGRP) is essential for resistance against fungal pathogen and opportunistic pathogenic gut bacteria in Locusta migratoria manilensis. | Pattern recognition proteins, which form part of the innate immune system, initiate host defense reactions in response to pathogen surface molecules. The pattern recognition protein ß-1,3-glucan recognition protein (ßGRP) binds to ß-1,3-glucan on fungal surfaces to mediate melanization via the prophenoloxidase (PPO)-activating cascade. In this study, cDNA encoding a 53-kDa ßGRP (LmßGRP) was cloned from Locusta migratoria manilensis. LmßGRP mRNA shown to be constitutively expressed specifically i ... | 2011 | 22062247 |
| insights from the genome of ophiocordyceps polyrhachis-furcata to pathogenicity and host specificity in insect fungi. | ophiocordyceps unilateralis is an outstanding insect fungus for its biology to manipulate host ants' behavior and for its extreme host-specificity. through the sequencing and annotation of ophiocordyceps polyrhachis-furcata, a species in the o. unilateralis species complex specific to the ant polyrhachis furcata, comparative analyses on genes involved in pathogenicity and virulence between this fungus and other fungi were undertaken in order to gain insights into its biology and the emergence of ... | 2015 | 26511477 |
| metacridamides a and b, macrocycles from conidia of the entomopathogenic fungus metarhizium acridum. | metarhizium acridum, an entomopathogenic fungus, has been commercialized and used successfully for biocontrol of grasshopper pests in africa and australia. its conidia produce two novel 17-membered macrocycles, metacridamides a and b, which consist of a phe unit condensed with a nonaketide. planar structures were elucidated by a combination of mass spectrometric and nmr techniques. following hydrolysis of 1, chiral amino acid analysis assigned the l-configuration to the phe unit. a crystal struc ... | 2012 | 22292922 |
| an ena atpase, maena1, of metarhizium acridum influences the na(+)-, thermo- and uv-tolerances of conidia and is involved in multiple mechanisms of stress tolerance. | in fungi, ena atpases play key roles in osmotic and alkaline ph tolerance, although their functions in thermo- and uv-tolerances have not been explored. entomopathogenic fungi are naturally widespread and have considerable potential in pest control. an ena atpase gene, maena1, from the entomopathogenic fungus metarhizium acridum was functionally analyzed by deletion. maena1-disruption strain (δmaena1) was less tolerant to nacl, heat, and uv radiation than a wild-type strain (wt). digital gene ex ... | 2015 | 26325214 |
| involvement of an alternative oxidase in the regulation of hyphal growth and microsclerotial formation in nomuraea rileyi cqnr01. | mitochondria of nomuraea rileyi contain an alternative oxidase (aox), which reduces oxygen to water by accepting electrons directly from ubiquinol. furthermore, through a transcriptional analysis, we found that an alternative oxidase (nraox) was up-regulated during microsclerotial formation. to study the function of nraox, nraox was cloned from n. rileyi cqnr01. the full-length cdna was 1266 bp with an open reading frame of 1068 bp encoding 355 amino acids. a phylogenetic analysis revealed that ... | 2015 | 26135515 |
| enhancing the utilization of host trehalose by fungal trehalase improves the virulence of fungal insecticide. | entomopathogenic fungi proliferate in insect hemolymph by using host nutrients after penetrating the cuticle. to improve the virulence of the locust specific fungus, metarhizium acridum, we genetically modified the fungus to overexpress atm1, an endogenous hydrolase of trehalose, which is the main carbon source in insect hemolymph. compared with the wild-type strain, metarhizium acridum overexpressing atm1 gene secreted more acid trehalase into locust hemolymph. the trehalose concentrations in l ... | 2015 | 26115754 |
| differential expression of the pr1a gene in metarhizium anisopliae and metarhizium acridum across different culture conditions and during pathogenesis. | the entomopathogenic fungi of the genus metarhizium have several subtilisin-like proteases that are involved in pathogenesis and these have been used to investigate genes that are differentially expressed in response to different growth conditions. the identification and characterization of these proteases can provide insight into how the fungus is capable of infecting a wide variety of insects and adapt to different substrates. in addition, the pr1a gene has been used for the genetic improvemen ... | 2015 | 25983629 |
| the acid trehalase, atm1, contributes to the in vivo growth and virulence of the entomopathogenic fungus, metarhizium acridum. | for pathogens, the ability to acquire available nutrients in a host is a key to their survival and replication. entomopathogenic fungi of the genus metarhizium secrete trehalase, which enables them to use trehalose, the predominant sugar in insects. here, the roles of the acid trehalase gene (atm1) in the in vivo growth and virulence of metarhizium acridum were investigated. phenotypic analysis showed that disruption of atm1 severely reduced fungal growth on exogenous trehalose as the sole carbo ... | 2015 | 25865794 |
| integration of an insecticidal scorpion toxin (bjαit) gene into metarhizium acridum enhances fungal virulence towards locusta migratoria manilensis. | entomopathogenic fungi have been developed as biopesticides, but poor efficacy has blocked their application. one approach to improving virulence is by genetic manipulation. bjαit from the venom of buthotus judaicus is an insect-selective neurotoxin. to clarify the insecticidal potency of bjαit as a virulence candidate in microbial biocontrol agents, the entomopathogenic fungus metarhizium acridum was genetically modified with bjαit, and its resulting activity against locusts (locusta migratoria ... | 2015 | 25488590 |
| masnf1, a sucrose non-fermenting protein kinase gene, is involved in carbon source utilization, stress tolerance, and virulence in metarhizium acridum. | the protein kinase sucrose non-fermenting-1(snf1) regulates the derepression of glucose-repressible genes and plays a major role in carbon source utilization. in this study, masnf1, a sucrose non-fermenting protein kinase gene, has been identified from the entomopathogenic fungus metarhizium acridum, which has a great potential as a biocontrol agent. the functions of masnf1 were characterized using gene disruption and complementation strategies. disruption of masnf1 reduced the conidial yield an ... | 2014 | 25213916 |
| expression of scorpion toxin lqhit2 increases the virulence of metarhizium acridum towards locusta migratoria manilensis. | lqhit2 is an insect-specific neurotoxin from the venom of scorpion. in this study, the lqhit2 gene was introduced into the entomopathogenic fungus, metarhizium acridum. the virulence of the genetically modified strain malqhit2 was then evaluated against locusts (locusta migratoria manilensis). compared with the wild-type strain, the median lethal cell density (lc50) for malqhit2 was a 22.6-fold lower, and the median times to death (lt50) for malqhit2 were reduced by 30.3 and 29.6 %, respectively ... | 2014 | 25168679 |
| calcineurin modulates growth, stress tolerance, and virulence in metarhizium acridum and its regulatory network. | calcineurin is highly conserved and regulates growth, conidiation, stress response, and pathogenicity in fungi. however, the functions of calcineurin and its regulatory network in entomopathogenic fungi are not clear. in this study, calcineurin was functionally analyzed by deleting the catalytic subunit macna from the entomopathogenic fungus metarhizium acridum. the δmacna mutant had aberrant, compact colonies and blunt, shortened hyphae. conidia production was reduced, and phialide differentiat ... | 2014 | 24931310 |
| construction of a hypervirulent and specific mycoinsecticide for locust control. | locusts and grasshoppers (acridids) are among the worst pests of crops and grasslands worldwide. metarhizium acridum, a fungal pathogen that specifically infects acridids, has been developed as a control agent but its utility is limited by slow kill time and greater expense than chemical insecticides. we found that expression of four insect specific neurotoxins improved the efficacy of m. acridum against acridids by reducing lethal dose, time to kill and food consumption. coinoculating recombina ... | 2014 | 25475694 |
| screening of high toxic metarhizium strain against plutella xylostella and its marking with green fluorescent protein. | entomopathogenic fungus is proposed to be one of the best biocontrol agents against the destructive insect pest plutella xylostella. in this study, we tested the virulence of 11 metarhizium strain isolates against p. xylostella using a leaf dipping method, and found one strain, named 609, which had displayed the highest pathogenicity. bioassay results showed that the accumulated corrected mortality rate was 86.7 % on the eighth day after inoculation with a spore concentration 1 × 10(8) conidia/m ... | 2014 | 25037866 |
| diet drives the collective migrations and affects the immunity of mormon crickets and locusts: a comparison of these potential superspreaders of disease. | differential transmission of disease among individuals within a population or among species in a community can result in superspreaders, relatively rare individuals responsible for a large proportion of transmission events. migrating mormon crickets and nymphal locusts readily engage in cannibalistic attacks and necrophagy. typically multiple individuals consume a cadaver, which fosters the spread of disease. cannibalistic attacks result in aligned, coordinated movement of individuals in massive ... | 2016 | 27252211 |
| responsiveness of entomopathogenic fungi to menadione-induced oxidative stress. | entomopathogenic fungi are predisposed to ros induced by heat and uv-a radiation when outside the insect host. when inside the host, they are subject to phagocytic cells that generate ros to eliminate invading pathogens. the oxidative stress tolerance of the entomopathogenic fungi aschersonia aleyrodis (arsef 430 and 10276), aschersonia placenta (arsef 7637), beauveria bassiana (arsef 252), isaria fumosorosea (arsef 3889), lecanicillium aphanocladii (arsef 6433), metarhizium acridum (arsef 324), ... | 2014 | 25457946 |
| mycosis inhibits cannibalism by melanoplus sanguinipes, m. differentialis, schistocerca americana, and anabrus simplex. | cannibalism is common among the acrididae and the mormon cricket, anabrus simplex haldeman (orthoptera: tettigoniidae). this behavior has been proposed as a mechanism for the horizontal transmission of microsporida and entomopathogenic fungi. aanecdotal observations suggested that the migratory grasshopper, melanoplus sanguinipes fabricius (acrididae), and a. simplex did not eat cadavers that had been killed by insect pathogenic fungi. the hypothesis tested was that a. simplex or m. sanguinipes ... | 2013 | 24786183 |
| cloning and characterization of a novel 2-ketoisovalerate reductase from the beauvericin producer fusarium proliferatum lf061. | the ketoisovalerate reductase (ec 1.2.7.7 ) is required for the formation of beauvericin via the nonribosomal peptide synthetase biosynthetic pathway. it catalyzes the nadph-specific reduction of ketoisovaleric acid to hydroxyisovalerate. however, little is known about the bioinformatics' data about the 2-kiv reductase in fusarium. to date, heterologous production of the gene kivrfp from fusarium has not been achieved. | 2012 | 22916830 |
| contributions of β-tubulin to cellular morphology, sporulation and virulence in the insect-fungal pathogen, metarhizium acridum. | β-tubulin is an elementary subunit of microtubules that form the cytoskeleton, participating in a wide range of cellular processes. the contributions of the single β-tubulin gene in affecting cell morphology, sporulation and virulence were examined in the entomopathogenic fungus metarhizium acridum. targeted gene knockout of β-tubulin resulted in resistance to benomyl but impaired proper nuclear segregation, lipid droplet transport, and deposition of chitin to the cell wall. m. acridum β-tubulin ... | 2017 | 28336393 |
| transcriptional analysis of the conidiation pattern shift of the entomopathogenic fungus metarhizium acridum in response to different nutrients. | most fungi, including entomopathogenic fungi, have two different conidiation patterns, normal and microcycle conidiation, under different culture conditions, eg, in media containing different nutrients. however, the mechanisms underlying the conidiation pattern shift are poorly understood. | 2016 | 27506833 |
| wright-giemsa staining to observe phagocytes in locusta migratoria infected with metarhizium acridum. | hemocytes are the first line of defense in the invertebrate immune system. understanding their roles in cellular immunity is important for developing more efficient mycoinsecticides. however, the exact classification of hemocytes has been inconsistent and the various types of phagocytes in locusta migratoria are poorly defined. herein, the wright-giemsa staining method and microscopy were employed to characterize the hemocytes of l. migratoria following infection by metarhizium acridum. hemocyte ... | 2016 | 27345377 |
| exposure of metarhizium acridum mycelium to light induces tolerance to uv-b radiation. | metarhizium acridum is an entomopathogenic fungus commonly used as a bioinsecticide. the conidium is the fungal stage normally employed as field inoculum in biological control programs and must survive under field conditions such as high ultraviolet-b (uv-b) exposure. light, which is an important stimulus for many fungi, has been shown to induce the production of m. robertsii conidia with increased stress tolerance. here we show that a two-hour exposure to white or blue/uv-a light of fast-growin ... | 2016 | 26884481 |
| the magas1 gene is involved in pathogenesis by affecting penetration in metarhizium acridum. | appressorium is a specialized infection structure of filamentous pathogenic fungi and plays an important role in establishing a pathogenic relationship with the host. the egh16/egh16h family members are involved in appressorium formation and pathogenesis in pathogenic filamentous fungi. in this study, a homolog of egh16h, magas1, was identified from an entomopathogenic fungus, metarhizium acridum. the magas1 protein shared a number of conserved motifs with other egh16/egh16h family members and s ... | 2012 | 22580306 |
| mamk1, a fus3/kss1-type mitogen-activated protein kinase gene, is required for appressorium formation, and insect cuticle penetration of the entomopathogenic fungus metarhizium acridum. | entomopathogenic fungi have great potential for development as insecticides. however, large-scale use of mycoinsecticides is partially limited by poor efficiency. in many fungal pathogens, the yeast and fungal extracellular signal-regulated kinase (yerk1) subfamily is crucial to the fungal pathogenicity. in this study, a fus3/kss1-type mitogen-activated protein kinase (mapk) gene mamk1 (genbank accession no. efy93607) was identified in metarhizium acridum, which encodes a member of the yerk1 sub ... | 2014 | 24184951 |
| the tetraspanin gene mapls1 contributes to virulence by affecting germination, appressorial function and enzymes for cuticle degradation in the entomopathogenic fungus, metarhizium acridum. | in most eukaryotes, tetraspanins regulate cellular activities by associating with other membrane components. in phytopathogenic fungi, the tetraspanin pls1 controls appressorium-mediated penetration. however, regulation of pls1 and its associated signalling pathways are not clear. in this study, the mapls1 gene from the entomopathogenic fungus metarhizium acridum was functionally characterized. mapls1 was highly expressed in mycelium and appressorium, and accumulated on the plasma membrane or in ... | 2013 | 23809263 |
| metacridamide b methanol-d 4 monosolvate. | the title compound, c35h53no5·ch3oh {systematic name: (3s,6e,8s,9r,10e,12s,13s,14e,16s,17r)-3-benzyl-9,13-dihy-droxy-6,8,10,12,14,16-hexa-methyl-17-[(2s,4s)-4-methyl-hexan-2-yl]-1-oxa-4-aza-cyclo-hepta-deca-6,10,14-triene-2,5-dione methanol-d 4 monosolvate}, was extracted from conidia of the fungus metarhizium acridum. crystals were obtained as a methanol-d 4 solvate. the tail part of the 4-methyl-hexan-2-yl group exhibits disorder over two positions, with an occupancy ratio of 0.682 (9):0.318 ( ... | 2013 | 23723893 |
| large scale expressed sequence tag (est) analysis of metarhizium acridum infecting locusta migratoria reveals multiple strategies for fungal adaptation to the host cuticle. | to infect its insect host, the entomopathogenic fungus metarhizium acridum has to breach the physical barrier of the host cuticle to gain entry into insect tissue. to identify virulence-associated genes to improve the biocontrol efficacy of m. acridum, it is necessary to understand the genes expressed by m. acridum during its infection of the insect host cuticle. in this study, we performed a large scale gene expression analysis of m. acridum during locust cuticle infection. we report the identi ... | 2012 | 23052419 |
| mahog1, a hog1-type mitogen-activated protein kinase gene, contributes to stress tolerance and virulence of the entomopathogenic fungus metarhizium acridum. | fungal biocontrol agents have great potential in integrated pest management. however, poor efficacy and sensitivity to various adverse factors have hampered their wide application. in eukaryotic cells, hog1 kinase plays a critical role in stress responses. in this study, mahog1 (genbank accession no. efy85878), encoding a member of the hog1/sty1/p38 mitogen-activated protein kinase family in metarhizium (me.) acridum, was identified. targeted gene disruption was used to analyse the role of mahog ... | 2012 | 23038805 |
| the adenylate cyclase gene maac is required for virulence and multi-stress tolerance of metarhizium acridum. | the efficacy of entomopathogenic fungi in pest control is mainly affected by various adverse environmental factors, such as heat shock and uv-b radiation, and by responses of the host insect, such as oxidative stress, osmotic stress and fever. in this study, an adenylate cyclase gene (maac) was cloned from the locust-specific entomopathogenic fungus, metarhizium acridum, which is homologous to various fungal adenylate cyclase genes. rna silencing was adapted to analyze the role of maac in virule ... | 2012 | 22853879 |