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As a preliminary step in the study of dimorphism m Paracoccidioides brasiliensis, the effects of cyanem and ramihyphin A were studied. These antibiotics have been reported to induce morphological changes in fungi The results obtained suggest that ramihyphin A induce swelling of hyphae while partially inhibiting Y → M transformation with the production of an incipient and swollen mycelium. Cyanem did not affect the mycelial morphology as did ramihyphin A However, the Y → M transformation was inhibited and, also, the M → Y transformation was blocked with the production of a few yeast cells which were not released from the mycelium. [ABSTRACT FROM AUTHOR]

Fungi of the species Aspergillus niger exhibit a number of properties that can be exploited from biotechnology. Nowadays these properties are used for the mico-remediation of contaminated recalcitrant compounds such as hydrocarbons, specially aromatic moiety spaces which is the largest environmental interest. strain of A. niger was isolated from samples of Bay Amuay which was selected in media supplemented with anthracene as a representative of the HPA 400 ppm, tested on a test feasibility in culture media and applying treatability tests in samples of water from the bay through Biorremediation in vitro. The strain was identified macroscopically using Petri dish cultures and microscopically by wet chamber method, the various fruiting bodies were analyzed by Scanning Electron Microscopy (SEM). The strain evaluated presented high capacity of 75% removal efficiency in achievement test feasibility and remove 100% of the hydrocarbons in the treatability test. Morphostructural analysis showed the distinctive characteristics of the species in the hyphae and the various parts of fruiting bodies. The proposed changes conidia presented a cellular morphological modification of asexual spore against an adverse environment with contaminants of environmental interest as the HPA. [ABSTRACT FROM AUTHOR]

A wide range of mammals are susceptible to infection by the fungal species Coccidioides immitis and C. posadasii. In humans, 60% of infections are asymptomatic; however, certain patients may develop a severe and deep systemic mycosis called coccidioidomycosis. Genetic analysis suggests that the majority of clinical isolates recovered from South America are C. posadasii; however, little is known about the prevalence, species distribution, and ecological factors that favor the occurrence of this pathogen in those areas. By using a combined quantitative polymerase chain reaction (qPCR)-based approach and mycobiome amplicon sequencing, we provide evidence that at least two genotypes of C. posadasii are found in the xerophytic environment in Venezuela. We detected a 3806-fold range in the amount of Coccidioides DNA when comparing among the sampled locations, which indicates that human exposure risk is variable, and is one critical factor for disease manifestation. We identified fungal communities that are correlated with a higher prevalence of C. posadasii, suggesting that a combination of specific microbes and a xeric microenvironment may favor the growth of Coccidioides in certain locations. Moreover, we discuss the use of a combinatorial approach, using both qPCR and deep-sequencing methods to assess and monitor fungal pathogen burden at outbreak sources.

Large amount of drilling waste associated with the expansion of the Orinoco Oil Belt (OOB), the biggest proven reserve of extra-heavy crude oil (EHCO) worldwide, is usually impregnated with EHCO and highly salinized water-based drilling fluids. Oxidative exoenzymes (OE) of the lignin-degrading enzyme system (LDS) of fungi catalyse the oxidation of a wide range of toxic pollutants. However, very little evidences on fungal degradation or biotransformation of EHCO have been reported, which contain high amounts of asphaltenes and its biodegradation rate is very limited. The aims of this work were to study the ability of Pestalotiopsis palmarum BM-04 to synthesize OE, its potential to biotransform EHCO and to survive in extreme environmental conditions. Enzymatic studies of the LDS showed the ability of this fungus to overproduce high amounts of laccase (LACp) in presence of wheat bran or lignin peroxidase (LIPp) with EHCO as sole carbon and energy source (1300 U mgP(-1) in both cases). FT-IR spectroscopy with Attenuated Total Reflectance (ATR) analysis showed the enzymatic oxidation of carbon and sulfur atoms in both maltenes and asphaltenes fractions of biotreated EHCO catalysed by cell-free laccase-enriched OE using wheat bran as inducer. UV-visible spectrophotometry analysis revealed the oxidation of the petroporphyrins in the asphaltenes fraction of biotreated EHCO. Tolerance assays showed the ability of this fungus to grow up to 50,000 p.p.m. of EHCO and 2000 mM of NaCl. These results suggest that P. palmarum BM-04 is a hopeful alternative to be used in remediation processes in extreme environmental conditions of salinity and EHCO contamination, such as the drilling waste from the OOB., (© 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

The purpose of this study was to confirm the presence of Scytalidium dimidiatum on Mangifera indica (mango) trees, in a plantation managed by a diabetic patient with a white grain mycetoma of the foot caused by the same fungus. Samples from necrotic apices, roots, burned leaves and rotten stems from eight trees were processed by the Smith and Furcolow's mineral oil technique (modified). Several isolates from the apex material and clinical samples from the diabetic patient isolated in pure culture a fungus with the macroscopic and microscopic characteristics of that in S. dimidiatum. This fungus should be considered as an opportunistic microorganism for both humans and M. indica.

In Falcon State, Venezuela, human chromomycosis is mainly caused by a dimorphic fungus, Cladophialophora carrionii. Xerophytes plants are common in the State and goat breeding in an extensive system as the main way of living. There are not published reports of chromomycosis in goats, despite the fact of their permanent exposition to fungus by accidental inoculation with infected spines. To evaluate parasitic transformation to sclerotic cells, length of fungus-surviving period and histopathological lesions, goats of five months of age were inoculated with 1 x 10(6) cells of C. carrionii by subcutaneous route in the neck and biopsies at 10, 19, 30 and 60 days from inoculated places were performed. Tissues were analyzed by (a) direct test with KOH 10%; (b) inoculation in Saboraud dextrose culture and (c) histopathological techniques. Hyphae and sclerotic cells were observed on tissues treated with KOH 10%; growing of fungus was detected in specific medium up to four weeks post-inoculation. Tissue pathology showed necrotic foci, mixed polymorphonuclear infiltrate, predominance of mononuclear cells, lymphocytes, plasmocytes, cosinophils and giant cells, hyphae and sclerotic cells in each one of samples. C. carrionii caused cellular reactions in goats as those seen in humans at the first stages of infection; however, animals did not develop the typical macroscopic lesions of the human disease.

Superficial mycoses are considered to affect more frequently patients with type 2 diabetes mellitus (DM-2), specially onychomycosis and Tinea pedis. The purpose of this study was to compare the dermatophytoses, candidiasis and Pitiriasis versicolor frequency between 40 patients with DM-2 and 40 healthy persons of either sex, 40 years old or more. Clinical, metabolic, mycologic and inmunologic studies against Candida albicans, were carried out. Both diabetics 75% (30/40) and controls 65% (26/40) presented a high frequency of superficial mycoses (no significant difference p = 0.329). Pitiriasis versicolor was not detected in diabetic patients. They presented Tinea unguium, concomitant with Tinea pedis, with a higher frequency. The predominant dermatophyte was Trichophyton rubrum 18/23 (78%) in diabetics and 8/16 (50%) in non diabetics. Candida was isolated as commensal from oral mucous: 23/40 (58%) in diabetics and 21/40 (52%) in non diabetics (serotipo A was the more frequent), and from onychomycosis: 11/40 (28%) in diabetics and 12/40 (30%) in non diabetics. The immunological response was the same in both groups: celular 100%, humoral 20%. No statistical correlation among superficial mycoses, blood glucose level, glycosylated hemoglobin values or the time suffering the disease was observed. The high susceptibility to dermatophytes and Candida sp. infection showed to be associated with age and no with the diabetic type 2 condition in those patients.

A case of chromomycosis induced by Rhinocladiella aquaspersa is decribed in Falcon State, which is considered as the first case in Venezuela, and the fifth one in the whole world of this species of Rhinocladiella. The case was observed in a five year-old child from the south part of Falcon State. The child presented wounds of two years of duration, in his upper left limb. These wounds were characterized by queloide cicatrices, and contiguous nodules, with a scalyo-scab surface. The disease was diagnosed through direct observation of cells extracted from the wounds and cleared with potassium hydroxide at 10%. The identification of R. aquaspersa was made by 1) The isolation in culture, using Lactritmel, Sabouraud-agar and Sablac as culture media; and 2) By observation, in slide culture, of dissemination structures characterized by erect conidiophores which were either simple or branched. The thermo-tolerance test applied indicate an optimum development temperature of 28 degrees C. It was not possible to reproduce the illness in Balb/c mice. The patient showed an unsatisfactory response to Itraconazol medication and improvement to an external local application therapy. Up to the present time, 370 cases of chromomycosis have been studied in Falcon State, with 21 cases in children. The suggests the existence of a susceptibility to this kind of mycosis from childhood.

This is a report of three cases of mycetome studied in our laboratory during the last four years. We also informed about the evolution of the first case produced by Pyrenochaeta romeroi nova species reported by Borelli in 1959. All the patients were farmer men, 18, 42 and 54 years old, from the semiarid and subhumid zones of Falcon State, located on the northwest region of Venezuela. Clinically, all patients presented the mycetome syndrome (subcutaneous edema, sinus tract and "granules"), with a evolution of six months to three years. The lesions were localized in the inferior limbs in two of the patients and in the thorax in one of them. The clinical diagnose was confirmed by microbiological and mycological studies, isolating Nocardia brasiliensis in two cases and Madurella grisea in one. Two patients treated with Sulfas showed remission of the disease in a two years follow up. Including this report, 15 cases of mycetome have been reported in the Falcon State (Venezuela) in a period of thirty five years, representing only 9, 14% of the national casuistic. Actinomadura madurae and N. brasiliensis have been the most frequently isolated agents in this region. In order to determine the real endemicity of the mycetome in Venezuela, multidisciplinary clinical, inmunological, microbiological and epidemiological studies are recommended. According to the reported casuistic (15 cases), the mycetome should be a low frequency disease in Falcon State, Venezuela. We confirm that early diagnosis favors an efficient therapy.

Three strains of Cladosporium carrionii, two human isolates and one from a xerophilous plant, were used to study the effect of culture conditions in 106 newborn ddY mice. Growth in a complex medium (YPG) and a basal synthetic medium (BSM) was compared. Filamentous forms developed during static incubation while conidia were readily formed with shaking. Mice inoculated intraperitoneally were sacrificed and autopsied after 4 weeks. Mortality was related only to sporulated exponential phase growing cells. Invasiveness ability was preserved in all experimental conditions. BSM medium that inhibited exopigment formation appeared more suitable than YPG to obtain intact cells for further studies. Biochemical and physiological alteration associated with shape changes during differentiation of vegetative cells into spores could play an important role in virulence of C. carrionii.

Four strains of Histoplasma capsulatum were analyzed to observe any variations in their cell wall composition. Strain G-184B produced the same amount of sugars reported by Domer (2) although qualitative analyses agreed with Kanetsuna's report (4) as far as the presence of glucose, galactose, and mannose was concerned. Our results agree with previous reports in classifying H. capsulatum into chemotypes I and II, the latter having more alpha-glucan in its cell wall. A decrease in the amount of fraction 2 (alpha-glucan) of strain G-184B was observed when the strain was subcultured in vitro for many years, an effect similar to that reported for Paracoccidioides brasiliensis (12, 13).

Spherical and osmotically sensitive protoplasts were released from cultures of the yeast-like form of Paracoccidioides basilienisis strain IVIC Pb9 through the action of a mixture of crude enzyme preparations: alpha and beta-glucanases and chitinase, obtained from culture filtrates of Cladosporium resinae, Basidiomycete QM 806 and Streptomyces sp respectively. The highest efficiency of protoplast liberation was achieved when each crude enzyme preparation was used at 1 mg/ml.