Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Entomophthora”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMed1977

[Tropical entomophthoromycoses].

A review was made about human entomophthoromycosis observed in tropical areas due to fungi of the order Entomophthorales. Rhinophycomycosis is caused by Entomophthora coronata, a cosmopolitan fungus which is only pathogen in wet tropical and subtropical climates. The disease, a muco-cutaneous infection of the face, induces monstruous deformations. Basidiobolomycosis is caused by Basidiobolus meristosporus, a saprophyte of different amphibians and reptiles very often present in the family Agamidae. The disease interests the subcutaneous tissues and is mainly located at the trunk, shoulders and upper part of the limbs. The epidemiology, clinic and therapeutic were reported. Histopathological lesions and morphology of both fungi were studied. The etiology of the casual agents of these mycoses was discussed.

Adult↗
PubMed1978

[A new culture medium for growth and sporulation of Entomophthorales species, pathogens of aphids (author's transl)].

No one of the 3 specific egg yolk fractions (neutral lipids, polar lipids and proteins) was necessary for growth and sporulation of species such as Entomophthora aphidis, E. phalloides and E. thaxteriana, normally grown on egg yolk media. Egg yolk could be replaced by a sunflower oil-yeast extract mixture. E. thaxteriana was especially well studied. Various animal and vegetable fats and even chemically pure triglycerides could replace sunflower oil as a carbon source. Yeast extract was the best nitrogen source tested. In liquid culture, sporulation was directly dependent on yeast extract concentration. When yeast extract concentration was held constant, an increase in oil concentration did not produce an increase in sporulation. High dextrose concentrations inhibited resting spore formation. Liquid cultures of E. thaxteriana regularly produced 3 x 10(6) azygospores/ml in a 20 l fermentor.

Animals↗
PubMedDate not supplied

[Metabolic transformation of labelled exogenous fatty acids by fungal cultures of the family Entomophthoraceae].

Entomophthora coronata 1932 and E. conica 1716 are quite different in their fatty acid composition and the unsaturation degree of synthesized lipids. The cultures were used as models to study metabolic transformations of exogenous 14C-labeled acetic, palmitic, stearic and oleic acids as well as to compare the activities of the synthetase and desaturase enzyme complexes. The cultures were capable of transforming exogenous acetic and fatty acids into polyunsaturated arachidonic acid. E. coronata 1932 whose lipids mainly contain fatty acids with a short chain could metabolize unsaturated oleic acid to yield polyene fatty acids. However, this culture metabolized exogenous acids at a far lower rate as compared with E. conica 1716. The high content of saturated fatty acids with a short chain in the lipids might be due to the specific action of the synthetase complex and to the low activity of the desaturation enzymes. It has been demonstrated for the first time that exogenous oleic acid is converted at a high rate by the cells into arachidonic acid, a precursor of prostaglandin compounds.

Biotransformation↗
PubMedDate not supplied

[Entomophthorosis of Culex pipiens (Culicidae) mosquitoes breeding in basements].

Foci of mycosis of C. p. pipiens and C. p. molestus caused by the parasitic fungus Entomophthora conglomerata Sorok. were found out in basements flooded with water. The conditions prevailing in the foci, sites of infection of mosquitoes and seasonal changes in the epizootic process are described. Developmental periods of conidiospores in mosquitoes were established experimentally. Entomophthorosis epizootia was found to limit the possibilities of mosquitoes to scatter from the hatching sites and to reduce the number of biting females in the population.

Animals↗
PubMedDate not supplied

[Influence of lipids and fatty acids of egg yolk over growth and sporulation of Entomophthorales (author's transl)].

Proteic and lipidic fractions of the egg yolk were chemically isolated and used in solid synthetic media to study sporulation of 4 species of Entomophthorales. Neutral lipids are as good for growth and sporulation as polar lipids; the proteic fraction is only utilized as a nitrogen source. No specific factor of the sporulation was shown. The effect of fatty acids is studied: caproic, lauric, myristic, palmitic and oleic acids are the best for growth and sporulation. The results are discussed in view of considering the role of the lipids of the egg yolk and aphids on the physiology of Entomophthora.

Aphids↗
PubMed2001

Geographical distribution and host range of entomophthorales infecting the green spruce aphid Elatobium abietinum Walker in Iceland.

Entomophthora planchoniana and Neozygites fresenii caused infection in populations of the green spruce aphid, Elatobium abietinum, in Iceland. On this aphid species En. planchoniana was exclusively found in the western part of Iceland, while N. fresenii was exclusively found in the eastern part of Iceland. This discrete and nearly nonoverlapping geographical distribution correlates with the distribution of two different populations of El. abietinum found in Iceland. On other aphid species N. fresenii, En. planchoniana, Pandora neoaphidis, and Conidiobolus obscurus were documented throughout the country. Transmission experiments showed that Pa. neoaphidis and En. planchoniana could infect the eastern population of El. abietinum, although they have never been found on this population in nature. This strongly indicates that there is little or no interaction among El. abietinum, other aphids, and their respective entomophthoralean fungi in the field. Furthermore, this study is the first to record epizootics caused by N. fresenii and En. planchoniana in the subpolar region.

Animals↗
PubMed1997

Sterols of the phylum zygomycota: phylogenetic implications.

The sterol composition of 42 fungal species representing six of the eight orders of the Zygomycota was determined using gas-liquid chromatography-mass spectrometry to assess whether the distribution of major sterols in this phylum has taxonomic or phylogenetic relevance. Ergosterol, 22-dihydroergosterol, 24-methyl cholesterol, cholesterol, and desmosterol were detected as the major sterols among the species studied. Ergosterol was the major sterol of the Dimargaritales, Zoopagales, and 13 of the 14 Mucorales families included in this study. Desmosterol appeared to be the characteristic sterol of the Mortierellaceae (Mucorales), 24-Methyl cholesterol was the major sterol of the Entomophthorales genera Entomophthora, Conidiobolus and Basidiobolus, but cholesterol was the sole sterol detected in Delacroixia coronatus. The Kickxellales species analyzed in this study were characterized by 22-dihydroergosterol as the major sterol. These results suggest that certain orders of the Zygomycota may be distinguished on the basis of major sterol. Also, if sterol structure has phylogenetic implications, then orders might be arranged in the order Kickxellales (C28 delta 5,7)-->Dimargaritales, Zoopagales and Mucorales (C28 delta 5,7,22) on the basis of evolution of the predominant and presumably most competent sterol, ergosterol. Although the Entomophthorales would be expected to be more primitive than the above orders based on the predominance of C28 delta 5, it is not apparent from these data that members of the Zygomycota with ergosterol or its precursors as major sterols evolved from this taxon or the Chytridiomycota.

Cholesterol↗
PubMedDate not supplied

Influence of commercially derived lipids and a surfactant on the mode of germination and process of germ-tube formation in primary conidia of two species of Erynia subgenus Neopandora (Zygomycotina: Entomophthorales.

Primary conidia of the entomopathogens Erynia (subgenus Neopandora) delphacis (1 isolate) and Erynia (Neopandora) neoaphidis (3 isolates) were stimulated to form germ-tubes with Tween 20 and with free, long-chain fatty acids, each incorporated into Entomophthora complete medium (ECM). When combined with other basal media (three tested), these compounds did not stimulate germ-tube formation. Triacylglycerols and vegetable oils, added to the same media, allowed almost complete resporulation in the fungi. In both species, Tween 20 (0.1%) encouraged greater germ-tube production (41-69%) than the fatty acids (0.1%) (< or = 36%). For E. delphacis, Tween 20 and the fatty acids differed significantly, but for E. neoaphidis the differences were almost always insignificant. Myristic and oleic acids stimulated germ-tube formation in both species. Palmitic acid allowed almost complete resporulation of the fungi, except for one isolate of E. neoaphidis that formed germ-tubes. Linoleic acid, tested only for E. delphacis, was fungistatic to most conidia. Higher concentrations of the fatty acids (< or = 1%) did not increase germ-tube formation, except 1% oleic acid which affected E. delphacis alone (>80% germination and germ-tubes). Linoleic acid, and sometimes also myristic and oleic, were fungistatic and/or toxic, depending on their concentration and on medium composition. Addition of fatty acids to ECM usually extended the lag period, and altered the morphology of the conidia and germ-tubes. These phenomena were not observed with Tween 20. Colonies were formed by E. delphacis alone, stimulated by ECM supplemented with Tween 20 or fatty acids. The results are discussed with respect to biological and physiological aspects of germination, and with respect to the mode of action of the fatty acids and the surfactant.

Journal Article↗
PubMed2004

Observation on the initial inoculum source and dissemination of Entomophthorales-caused epizootics in populations of cereal aphids.

A total number of 1092 migratory alates were trapped from air in wheat grown area of Yuanyang County, Henan Province from early April through May 2002 in order to confirm the source and dissemination of entomophthoralean inocula to cause epizootics of cereal aphids. Those included 415 Sitobion avenae, 642 Rhopalosiphum padi, 22 Metopolophium dirhodum, and 13 Schizaphis graminum. The trapped alates were daily collected and individually reared for 7 days on wheat plants in laboratory. Of those 341 alates died of fungal infection, taking 31.2% in the trapped alates. These included 224 S. avenae, 106 R. padi, 8 M. dirhodum, and 3 S. graminum. Deaths of all infected alates occurred during the first 5 days and 78.9% of the deaths occurred within the first 3 days. Individual examination under microscope proved that all deaths were attributed to entomophthoralean fungi. Of those Pandora neoaphidis accounted for 84.6%, Conidiobolus obscurus for 9.9%, and Entomophthora planchoniana for 5.5%. Four alate deaths died of cross infection of P. neoaphidis and C. conidiobolus. Based on the high infection rate of the migratory alates trapped from air and the field occurrence of epizootics in populations of cereal aphids during the trapping period, Entomophthorales-caused epizootics were likely disseminated by infected alates through their flight and colonization. This makes it reasonable to interpret worldwide distribution of aphid epizootics, particularly caused by P. neoaphidis that has no resting spores discovered.

Animals↗
PubMed2006

Mucocutaneous entomophthoramycosis acquired by conjunctival inoculation of the fungus.

Entomophthoramycoses are classified into subcutaneous, mucocutaneous, and primary visceral forms. The mucocutaneous form, also known as rhinoentomophthoramycosis, involves the mucosa and subcutaneous tissues of the nose and is caused by Conidiobolus coronatus (Entomophthora coronata). In this report, we describe the first case of mucocutaneous entomophthoramycosis acquired by introduction of the fungus through the conjunctival mucosa as a consequence of trauma involving contamination with soil. The patient was a 37-year-old man with no other complaints. The lesion was tumoral and extended into the ethmoidal and maxillary sinuses. The histopathologic appearance of the lesion was characteristic of this infection with a granulomatous process rich in eosinophils and with hyphae surrounded by an eosinophilic, periodic acid-Schiff stain-positive halo (Splendore-Hoeppli phenomenon). To the best of our knowledge, this case constitutes the first report of mucocutaneous entomophthoramycosis acquired by ocular contamination.

Adult↗
PubMed1998

Mycosis of bandedwinged whitefly (Trialeurodes abutilonea) (Homoptera: aleyrodidae) caused by Orthomyces aleyrodis gen. & sp. nov. (Entomophthorales: Entomophthoraceae).

A new genus and species of fungus, Orthomyces aleyrodis Steinkraus, Humber & Oliver gen. & sp. nov. (Entomophthorales: Entomophthoraceae) is described. In 1994 and 1995, this fungus caused epizootics in high populations of bandedwinged whitefly (Trialeurodes abutilonea) on cotton and cocklebur in Alabama. In 1996, T. abutilonea populations were lower and no infected specimens were found. This is the first report of an entomophthoralean infecting an aleyrodid in the New World and the first report of entomophthoralean epizootics in whiteflies.

Animals↗
PubMed1998

Influence of substrate type and temperature on the developmental morphology of Pandora neoaphidis (Zygomycetes: entomophthorales), a pathogen of the tobacco aphid (Homoptera: aphididae).

Developmental morphology of Pandora neoaphidis was observed on the surfaces of the tobacco aphid, Myzus nicotianae, tobacco leaves (Nicotiana tabacum), and glass coverslips at 13 and 20 degrees C for 12 and 24 h postinoculation. Pandora neoaphidis responded similarly on the two living substrates, but differed on the inert coverslips. The proportions of ellipsoid conidia (primary and secondary) were similar on all substrates. Higher proportions of appressoria and lower proportions of round secondary conidia and germinating conidia occurred on the aphids and leaves than on the coverslips. Appressoria predominated over round secondary conidia and germinating conidia on the living substrates at 20 degrees C, but the opposite was seen at 13 degrees C. The proportions of ellipsoid conidia were similar at both temperatures. On coverslips, the proportions of appressoria and round secondary conidia were similar at both temperatures. However, the proportions of germinating and ellipsoid conidia were higher at 13 and 20 degrees C, respectively.

Animals↗
PubMed2001

Identification of symbiotic bacteria (Photorhabdus and Xenorhabdus) from the entomopathogenic nematodes Heterorhabditis marelatus and Steinernema oregonense based on 16S rDNA sequence.

Two species of entomopathogenic nematodes, Heterorhabditis marelatus and Steinernema oregonense, were described recently from the west coast of North America. It is not known whether the bacterial symbionts of these nematodes are also unique. Here we compared partial 16S rRNA sequences from the symbiotic bacteria of these two nematodes with sequence from previously described Photorhabdus and Xenorhabdus species. The 16S sequence from the new Xenorhabdus isolate appears very similar to, although not identical to, that of X. bovienii, the common symbiont of S. feltiae. The new Photorhabdus isolate appears to be very distinct from other known Photorhabdus species, although its closest affinities are with the P. temperata group. We also verified a monoxenic association between each isolate and its nematode by amplifying and sequencing bacterial 16S sequence from crushed adult and juvenile nematodes and from bacterial cultures isolated from infected hosts.

Animals↗
PubMed1992

Entomophthoromycosis due to Conidiobolus.

Entomophthoromycosis due to Conidiobolus coronatus is a granulomatous infection characterized by lesions that originate in the inferior turbinate, spread through ostia and foramina to involve the facial and subcutaneous tissues and paranasal sinuses. The majority of the cases have been described from areas of tropical rainforest in West Africa, agricultural and outdoor workers (aged 20-60 years) being the ones most frequently affected. The fungus is common in soil and decaying vegetation. Infection probably occurs by implantation of the spores of the fungus in nasal mucosa. C. incongruus is a rare agent of the disease, so far known only from two cases with lesions involving the pericardium, mediastinum, lungs, liver, oesophagus and jejunum. C. coronatus is known to cause a clinically similar disease in horses, mules, a dolphin and a chimpanzee. A characteristic histological feature is the presence of thin-walled, broad, often septate hyphae or hyphal fragments with a thick eosinophilic sheath, frequently phagocytosed within giant cells. The fungus is known to produce in vitro several enzymes, e.g., elastase, esterase, collagenase and lipase, which have a possible role in pathogenicity. A concentrated brain heart infusion culture filtrate antigen is useful for immunodiagnosis. Several drugs e.g., potassium iodide, cotrimoxazole, amphotericin B, ketoconazole and itraconazole have been tried with varying success. Investigations on the immunology of disease and the role of proteases and lipases in the pathogenesis of infection is an important area of further research.

Animal Diseases↗
PubMed1980

Gastrointestinal entomophthoramycosis caused by Basidiobolus haptosporus.

There was described the first cultural proven case of gastrointestinal entomophthoramycosis caused by B. haptosporus. A review of the literature on gastrointestinal zygomycosis led us to presume that similar clinical reported cases have been also caused by this fungus. A commentary on the designation of the clinical forms of the infections caused by Zygomycetes was also made.

Child, Preschool↗
PubMed1996

A serine alkaline protease from the fungus Conidiobolus coronatus with a distinctly different structure than the serine protease subtilisin Carlsberg.

In view of the functional similarities between subtilisin Carlsberg and the alkaline protease from Conidiobolus coronatus, the biochemical and structural properties of the two enzymes were compared. In spite of their similar biochemical properties, e.g., pH optima, heat stability, molecular mass, pI, esterase activity, and inhibition by diisopropyl fluorophosphate and phenylmethlysulfonylfluoride, the proteases were structurally dissimilar as revealed by (1) their amino acid compositions, (2) their inhibition by subtilisin inhibitor, (3) their immunological response to specific anti-Conidiobolus protease antibody, and (4) their tryptic peptide maps. Our results demonstrate that although they are functionally analogous, the Conidiobolus protease is structurally distinct from subtilisin Carlsberg. The Conidiobolus protease was also different from other bacterial and animal proteases (e.g. pronase, protease K, trypsin, and chymotrypsin) as evidenced by their lack of response to anti-Conidiobolus protease antibody in double diffusion and in neutralization assays. The Conidiobolus serine protease fails to obey the general rule that proteins with similar functions have similar primary sequences and, thus, are evolutionarily related. Our results strengthen the concept of convergent evolution for serine proteases and provide basis for research in evolutionary relationships among fungal, bacterial, and animal proteases.

Amino Acids↗
PubMed1976

Ultrastructure and light microscope appearance of Blastocystis hominis in a patient with enteric disease.

The patient reported had a fulminant, refractory diarrhea of unknown etiology producing about 81 of diarrheal fluid daily which required continuously large volumes of intravenous fluid therapy. No protozoon other than Blastocystis hominis was present. Bacterial counts were very low in the fecal material because of continuous antibiotic therapy. Blastocystis hominis was present in large numbers, averaging for a 5-day period, 8.3 X 10(6)/ml of diarrheal fluid. Treatment with metronidazole for 12 days had no effect on either the diarrhea or the numbers of B. hominis present. The patient died from aspiration pneumonia without a firm diagnosis of his underlying disease. Identification of an unusual form of B. hominis seen only in diarrheal fluid was confirmed through cultivation, specific fluorescent antibody staining, as well as by transmission electron microscopy and light microscopy using hematoxylin staining and Nomarski interference contrast. The most significant result of this study is the description of ultrastructure of the in vivo trophozoite form of B. hominis. The persistence of certain morphologic features of the in vivo and in vitro forms of B. hominis is described. In vivo, B. hominis has a larger nucleus than in vitro, more prominent, well structured nucleoli, and hundreds of mitochondria with numerous delicate saccular cristae in a clear electron-lucent matrix and complex internal structure. Many cytoplasmic vesicles lined with ribosomes are present. The in vivo structure differs from the granular culture form of B. hominis, which has a smaller nucleus (nuclei), no distinct nucleoli, mitochondria characterized by a uniform structureless electron dense matrix, and few cytoplasmic, ribosome-lined vesicles. A feature retained in both in vivo and in vitro B. hominis is a distinct crescentic band of nuclear chromatin.

Diarrhea↗