Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Conidiobolus”

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 73 records · Page 4Linked to original sources
PubMed2000

Evidence for tryptophan in proximity to histidine and cysteine as essential to the active site of an alkaline protease.

The presence, microenvironment, and proximity of an essential Trp with the essential His and Cys residues in the active site of an alkaline protease have been demonstrated for the first time using chemical modification, chemo-affinity labeling, and fluorescence spectroscopy. Kinetic analysis of the N-bromosuccinimide- (NBS) or p-hydroxymercuribenzoate- (PHMB) modified enzyme from Conidiobolus sp. revealed that a single Trp and Cys are essential for activity in addition to the Asp, His, and Ser residues of the catalytic triad. Full protection by casein against inactivation of the enzyme by NBS and quenching of Trp fluorescence upon binding of the enzyme with NBS, substrate (sAAPF-pNA), or inhibitor (SSI) confirmed participation of the Trp residue at the substrate/inhibitor binding site of the alkaline protease. Comparison of the K(sv) values for the charged quenchers CsCI (1.66) and KI (7.0) suggested that the overall Trp microenvironment in the protease is electropositive. The proximity of Trp with His was demonstrated by the sigmoidal shape of the pH-dependent fluorometric titration curve with a pK(F) of 6.1. The vicinity of Trp with Cys was indicated by resonance energy transfer between the intrinsic fluorophore (Trp) and 5-iodoacetamide-fluorescein labeled Cys (extrinsic fluorophore). Our results on the proximity of Trp with essential His and Cys thus confirm the presence of Trp in the active site of the alkaline protease.

Affinity Labels↗
PubMed2005

Rhino-orbitocerebral entomophthoramycosis.

Conidiobolus coronatus is recognized as a human pathogen causing subcutaneous fungal infection of the face in immunocompetent patients. The disease process is usually benign. We report, what we believe to be the first case of intracranial extension of C. coronatus producing rhino-orbitocerebral syndrome, and subsequent dissemination of C. coronatus in an immunocompetent patient.

Adult↗
PubMed2002

Distribution, occurrence and characterization of entomopathogenic fungi in agricultural soil in the Palestinian area.

The occurrence of entomopathogenic fungi was investigated in irrigated vegetable fields and citrus orchards soils, over a nine-month period (April-December 1999), using the Galleria bait method (GBM). Entomopathogenic fungi were found to occur in 33.6% of the soil samples studied, with positive samples yielding 70 fungal isolates, belonging to 20 species from 13 genera. Conidiobolus coronatus was the most frequent and abundant entomopathogenic species recovered, comprising 31.4% of the total number of isolates. Soil pH, soil moisture content and the geographical location had minor or no effect on the isolation of entomopathogenic fungi in the fields studied. On the other hand, organic matter content of soil, and vegetation type were found to significantly affect the occurrence of entomopathogenic fungi in soil habitats, with orchard fields yielding larger numbers of isolates than vegetable fields. Using Koch's postulates the pathogenicity of fungal isolates to Galleria larvae was found to range from 16-100% (mortality rate). Isolates of C. coronatus proved to be the most virulent isolates recovered. The effect of media and temperature on mycelial growth rate, conidial production and conidial germination of six entomopathogenic fungal species (C. coronatus, Entomophaga grylli, Erynia castrans, Hirsutella jonesii, Paecilomyces farinosus and Sporodiniella umbellata) was also studied. Mycelial growth rate, spore production and spore germination were significantly affected by media, temperature and isolates. In view of the present results, C. coronatus appears to be a good candidate for pest control in agricultural soils, as it has a wide tolerance to agricultural practices, has frequently been isolated from both vegetable and orchard fields, and is characterized by high mycelial growth rate, conidial production and conidial germination.

Animals↗
PubMed2002

Alpha-crystallin binds to the aggregation-prone molten-globule state of alkaline protease: implications for preventing irreversible thermal denaturation.

Alpha-crystallin, the major eye-lens protein with sequence homology with heat-shock proteins (HSPs), acts like a molecular chaperone by suppressing the aggregation of damaged crystallins and proteins. To gain more insight into its chaperoning ability, we used a protease as the model system that is known to require a propeptide (intramolecular chaperone) for its proper folding. The protease ("N" state) from Conidiobolus macrosporus (NCIM 1298) unfolds at pH 2.0 ("U" state) through a partially unfolded "I" state at pH 3.5 that undergoes transition to a molten globule-(MG) like "I(A)" state in the presence of 0.5 M sodium sulfate. The thermally-stressed I(A) state showed complete loss of structure and was prone to aggregation. Alpha-crystallin was able to bind to this state and suppress its aggregation, thereby preventing irreversible denaturation of the enzyme. The alpha-crystallin-bound I(A) state exhibited native-like secondary and tertiary structure showing the interaction of alpha-crystallin with the MG state of the protease. 8-Anilinonaphthalene sulphonate (ANS) binding studies revealed the involvement of hydrophobic interactions in the formation of the complex of alpha-crystallin and protease. Refolding of acid-denatured protease by dilution to pH 7.5 resulted in aggregation of the protein. Unfolding of the protease in the presence of alpha-crystallin and its subsequent refolding resulted in the generation of a near-native intermediate with partial secondary and tertiary structure. Our studies represent the first report of involvement of a molecular chaperone-like alpha-crystallin in the unfolding and refolding of a protease. Alpha-crystallin blocks the unfavorable pathways that lead to irreversible denaturation of the alkaline protease and keeps it in a near-native, folding-competent intermediate state.

Anilino Naphthalenesulfonates↗
PubMedDate not supplied

Rhinoentomophthoromycosis.

A sixty year old patient presented with a slowly progressive swelling of the nose, of one year duration, suggesting a clinical diagnosis of subcutaneous zygomycosis. On investigation, the tissue fungal culture grew Conidiobolus coronatus, confirming the diagnosis as rhinoentomophthoromycosis. He was treated with a combination of oral fluconazole and oral potassium iodide for a total period of 5 months. His symptoms subsided completely. Serial CT scanning of paranasal sinuses showed the gradual resolution of the swelling, in response to the treatment. Early detection of the disease and combination therapy gave rapid and good results. This is the first case of its kind to be reported from Kerala, the southern state of India.

Conidiobolus↗
PubMed1998

Relationships of the insect-pathogenic order Entomophthorales (Zygomycota, Fungi) based on phylogenetic analyses of nuclear small subunit ribosomal DNA sequences (SSU rDNA).

We sequenced the nuclear small subunit of ribosomal DNA (SSU rDNA) from seven species within the insect-pathogenic order Entomophthorales. These sequences were aligned with other published SSU rDNA sequences and phylogenies were inferred using phenetic and cladistic methods. Based on three different phylogenetic methods the Entomophthorales (excluding Basidiobolus ranarum) is monophyletic; B. ranarum was more closely related to chytrids from Chytridiales and Neocallimasticales than to Entomophthorales, as was proposed by Nagahama et al. (Mycologia 87: 203-209, 1995). Nuclear characters (large nuclei containing conspicuous condensed chromatin and lack of a prominent nucleolus) were of predictive value for the monophyly of the family Entomophthoraceae. Conidial characters separate the Entomophthoraceae, which only includes obligate pathogens, into at least two lineages: one lineage with uninucleate conidia and another with multinucleate conidia. The two species of Conidiobolus studied were paraphyletic in our analyses and only distantly related to each other. This information may prove to be important in the use of these fungi as biocontrol agents.

Animals↗
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↗
PubMed2001

Natural occurrence of entomophthoralean fungi pathogenic to collembolans.

The aim of this study was to assess the natural occurrence of fungi from the order Entomophthorales (Zygomycetes) pathogenic to a range of collembolan species. A total of 11,709 collembolans representing a total of 15 species from all three subclasses within Collembola were collected and incubated. Infection with Neozygites-like spp. (Entomophthorales) was recorded in the two subclasses, Arthropleona and Symphypleona. The morphology of the primary conidia of the Neozygites-like fungi infecting collembolans showed a high degree of variation in shape and size, and the fungi were divisible into five groups. One group consisted of Neozygites sminthuri, while the other four groups, while still closely resembling the genus Neozygites, did not fit within the description of any known species and were preliminarily designated Neozygites sp. nov. 1 to 4. Neozygites sp. nov. 1, infecting Sphaeridia pumilis, was observed to form globular secondary conidia, which have not been observed before within the genus Neozygites. A formal species description needs, however, yet to be performed. The infection was mainly found in species from the subclass Symphypleona, where two new host genera for Neozygites, Deuterosminthurus and Sphaeridia, were recorded. However, the prevalence of Neozygites spp. was low, up to 10% in S. pumilis, 6% in Sminthurus viridis, and below 1% in Deuterosminthurus sulphureus. Infection with an obligatory entomopathogenic fungus was for the first time well documented within the subclass Arthropleona, where specimens of Orchesella cincta and Orchesella villosa sporulated with a N. sminthuri-like fungus. Additionally, infection with the facultative pathogen Conidiobolus coronatus was recorded from several hosts representing both the subclass Arthropleona (Isotoma anglicana and O. cincta) and the subclass Symphypleona (Dicyrtoma sp. and S. viridis). For most species the prevalence of C. coronatus resembled that of Neozygites spp. and did not exceed 8.8%. The only exception was Dicyrtoma sp., for which the only associated entomophthoralean fungus was C. coronatus, where the prevalence reached 17.8% infection.

Animals↗
PubMed1975

[Growth and sporulation of 6 species of Entomophthorales. II. Effect of various nitrogen sources].

Growth and sporulation of Entomophthora near obscura, E. destruens, E. near thaxteriana, E. virulenta, Basidiobolus ranarum and Conidiobolus osmodes were studied in solid synthetic media containing various nitrogen sources at 0,33 g N/liter. Thirty two nitrogen sources representing nitrates, ammonium salts, amino acids and protein hydrolysates were tested. E. near obscura did not grow on any medium. Protein hydrolysates, ammonium salts and ten of the sixteen amino acids tested were the best nitrogen sources for growth and resting spores production of the five other species.

Amino Acids↗
PubMed1983

Investigations into the biology of three 'phycomycotic' agents pathogenic for horses in Australia.

Although 'phycomycosis' is a common disease of horses in northern Australia little is known about the causative fungi. In this paper the laboratory methods for diagnosis are described. These revealed 38 cases caused by Pythium sp. (Hyphomyces destruens), 6 cases caused by Basidiobolus haptosporus and 2 caused by Conidiobolus coronatus. Laboratory studies on the chemotatic behaviour of zoospores of Pythium sp. showed that they were strongly attracted to both animal hairs and plant tissue. Because of this behaviour a simple baiting method using human hair was used to trap the fungus from water samples taken from different locations near Townsville, Queensland. B. haptosporus was isolated by indirect culture from the faeces of 5 bearded dragon lizards (Amphibolurus barbatus) captured near a small creek near Brisbane. By combining previously published information with data obtained in the present study, ecological life-cycles for Pythium sp., B. haptosporus and C. coronatus are proposed. They include mechanisms whereby horses may become infected.

Animals↗
PubMed1992

Lipids of selected molds grown for production of n-3 and n-6 polyunsaturated fatty acids.

The lipid classes and component fatty acids of seven fungi were examined. Three marine fungi, Thraustochytrium aureum, Thraustochytrium roseum and Schizochytrium aggregatum (grown at 30, 25 and 25 degrees C, respectively), produced less than 10% lipid but contained docosahexaenoic acid (DHA) up to 30% and eicosapentaenoic acid (EPA) up to 11% of the total fatty acids. Mortierella alpinapeyron produced 38% oil containing solely n-6 polyunsaturated fatty acids (PUFA) with arachidonic acid (AA) at 11% of the total fatty acids. Conidiobolus nanodes and Entomorphthora exitalis produced 25% oil and contained both n-3 and n-6 PUFA, with AA at 16% and 18%, respectively. Saprolegnia parasitica produced 10% oil and contained AA and EPA, respectively, at 19% and 18%. The triacylglycerol fraction always represented the major component at between 44% and 68% of the total lipid. Each fungus, except T. aureum, had the greatest degree of fatty acid unsaturation in the phospholipid fraction. The triacylglycerol fraction of T. aureum was the most unsaturated with DHA representing 29% (w/w) of all fatty acids present. The presence of the enzyme ATP:citrate lyase correlated with the ability of molds to accumulate more than 10% (w/w) lipid when the fungi were grown in nitrogen-limiting media. In those molds that failed to accumulate more than 10% lipid, the enzyme was absent.

ATP Citrate (pro-S)-Lyase↗
PubMed2003

Rapid detection of pathogenic fungi from clinical specimens using LightCycler real-time fluorescence PCR.

In the study presented here a LightCycler real-time PCR system was used for the diagnosis of fungal infections from clinical tissue samples. Nine specimens were investigated from six patients with suspected or proven invasive fungal infections. Seven of nine samples were positive in a broad-range fungal PCR assay. In four samples, Aspergillus fumigatus was detected both by a species-specific hybridization assay as well as by sequencing of amplification products. In addition, the broad-range fungal PCR assay and PCR sequencing detected and identified, respectively, the following organisms in the specimens noted: Candida albicans in a culture-negative liver biopsy, Histoplasma capsulatum in a bone marrow sample, and Conidiobolus coronatus in a facial soft tissue specimen. Real-time PCR is a promising tool for the diagnosis of invasive fungal infections in human tissue samples and offers some advantages over culture methods, such as rapid analysis and increased sensitivity.

Aspergillus fumigatus↗
PubMed2004

Compatibility of alkaline xylanases from an alkaliphilic Bacillus NCL (87-6-10) with commercial detergents and proteases.

Alkaline xylanases from alkaliphilic Bacillus strains NCL (87-6-10) and Sam III were compared with the commercial xylanases Pulpzyme HC and Biopulp for their compatibility with detergents and proteases for laundry applications. Among the four xylanases evaluated, the enzyme from the alkaliphilic Bacillus strain NCL (87-6-10) was the most compatible. The enzyme retained its full activity (40 degrees C for 1 h) in the presence of detergents, whereas Pulpzyme HC and Sam III showed only 30% and 50% of their initial activity, respectively. Biopulp, though stable to detergents, had only marginal activity (5%)at pH 10. However, all four enzymes retained significant activity (80%) for 60 min in the presence of the proteases Alcalase and Conidiobolus protease. Supplementation of the enzyme enhanced the cleaning ability of the detergents.

Alkalies↗
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↗
PubMed1989

Immunological separation of Entomophthorales genera.

Exoantigens from Erynia neoaphidis, Conidiobolus major, C. thromboides, C. obscurus, Zoophthora radicans, and Basidiobolus ranarum were obtained from culture filtrates of fungal material grown in a yeast extract, peptone dialysate, dextrose medium and were tested against specific hyperimmune antisera prepared from E. neoaphidis, C. major, C. thromboides, and B. ranarum by the immunodiffusion technique. Specific precipitins were observed for E. neoaphidis and B. ranarum, while cross-reactions were detected among C. major, C. thromboides, and C. obscurus. The results suggest that genera of Entomophthorales can be easily separated by this simple immunological procedure.

Antigens, Fungal↗
PubMed1991

Nasofacial zygomycosis.

Zygomycosis is an uncommon polymorphic fungal disease. One clinical subtype, nasofacial zygomycosis, is caused by infectious exposure to the organism Conidiobolus coronatus. A case affecting the nose and lips of a 42-year-old Malay man is reported here. The clinicopathologic features and management of this disease are described, and its differential diagnosis is discussed.

Adult↗
PubMed1994

Treatment of tropical mycoses.

Several subcutaneous and deep-seated mycoses are either observed more frequently in the tropical areas or are restricted to certain regions within the tropics. These mycoses include sporotichosis, chromoblastomycosis, entomophthoromycosis, eumycetoma, lobomycosis, and paracoccidioidomycosis. In sporotrichosis and paracoccidioidomycosis, therapy often results in either complete resolution or marked improvement. For decades sporotrichosis has been treated successfully with potassium iodide, but recently the triazole compounds, especially itraconazole, have proved effective and free of major side effects. The usual therapy for paracoccidioidomycosis is sulfonamides or amphotericin B; the former requires prolonged treatment, whereas the latter causes a significant degree of toxicity. Various azole derivatives (ketoconazole, fluconazole, saperconazole, and itraconazole) allow shorter treatment courses, can be given orally, and are more effective. Presently, itraconazole is the drug of choice. Chromoblastomycosis is a difficult condition to treat, especially if it is caused by Fonsecaea pedrosoi. Several therapeutic approaches have been used, including heat, surgery, cryotherapy, thiabendazole, amphotericin B combined with flucytosine, and azole derivatives, but their success has been modest. A 65% response rate has been obtained with itraconazole given for periods of 6 to 19 months; in limited trials, saperconazole appears to be more effective and requires shorter treatment courses. Only a few patients with eumycetoma respond to therapy; 70% of patients with Madurella mycetomatis respond to prolonged treatment with ketoconazole. Griseofulvin has been tried in nonresponders with partial success. Limited data in patients with Fusarium species eumycetoma indicate good responses to itraconazole. Eumycetoma caused by Pseudallescheria boydii or Acremonium species has been refractory to therapy. Therapy of entomophthoromycosis is also difficult because the diagnosis is usually established late and not all patients respond to therapy; this situation applies to infection caused by either Basidiobolus haptosporus or Conidiobolus coronatus. Although there is no consensus, African physicians prefer to use potassium iodide or trimethoprim-sulfamethoxazole. Isolated reports indicate that the azole derivatives, including the triazoles, may be effective. As for lobomycosis, all attempts at medical treatment have failed. Surgery is successful only when the lesion is small and can be fully resected; repeated cryotherapy appears to be more successful.

Antifungal Agents↗
PubMed2003

Pythiosis, lagenidiosis, and zygomycosis in small animals.

Pythiosis, lagenidiosis, and zygomycosis affect animals living in temperate, tropical, and subtropical climates, and these diseases are often fatal. Although Pythium insidiosum, Conidiobolus species, and Basidiobolus species have been recognized as pathogens for several years, members of the genus Lagenidium have been identified as a cause of oomycosis in dogs only recently. Pythiosis, lagenidiosis, and zygomycosis share similar clinical and histologic characteristics, making them difficult to distinguish from one another; however, distinguishing between these pathogens is important because of differences in epidemiology, choice and duration of therapy, and prognosis.

Animals↗