Yeasts and fungi in excrements of the sand hill snail,Theba pisana

Eight microbial species were isolated and identified from excrements of the sand hill snail,Theba pisana, viz. 3 filamentous fungi, 3 basidiomycetous yeasts and 2 yeast-like ascomycetous fungi.     

Evaluation of Agar Candida ID2 (bioMerieux) a chromogenic medium for yeasts differentiation

Invasive diagnostic and therapeutic methods, widespread antibiotic therapy and rising percent of the immunocompromised patients cause incrementation of frequency of occurrence of the yeast infection. C. albicans is the most commonly isolated species of Candida from clinical samples. However, recently growth of frequency of isolation Candida non - albicans from clinical specimens have been observed. Yeast-like fungi different from C. albicans have become serious clinical problem. Conventional methods of identification of the yeast-like fungi carry away a lot time enough. Employment of chromogenic agar shortens latency on result. We decided to examine the usefulness ofAgar Candida ID2 (CAN2) (bioMérieux) in the identification of Candida species. The subjects within the study were 146 of Candida spp strains which were isolated from the clinical specimens of patients hospitalized at the University Hospital in Bydgoszcz. Germ tube test. Api 20C AUX test (bioMérieux) and Agar Candida ID2 (bioMérieux) were used. We have ascertained correspondence of identifying species amounted to 82.2% of analyzed Candida species between API 20C AUX test and kind of growth on CAN2 medium. Divergence of results received between CAN2 medium and API 20C AUX test suggests necessity of conducting of verification data with other methods. In conclusion, our study shows that Agar Candida ID2 is an effective medium for the isolation yeast-like fungi and in preliminary identification of Candida species direct from clinical materials.     

Yeasts from Macrobrachium amazonicum: a focus on antifungal susceptibility and virulence factors of Candida spp

In the present study, it was sought to compare yeast microbiota of wild and captive Macrobrachium amazonicum and evaluate the antifungal susceptibility and production of virulence factors by the recovered isolates of Candida spp. Additionally, cultivation water was monitored for the presence of fungi. Overall, 26 yeast isolates belonging to three genera and seven species were obtained, out of which 24 were Candida spp., with Candida famata as the most prevalent species for both wild and captive prawns. From cultivation water, 28 isolates of filamentous fungi were obtained, with Penicillium spp., Cladosporium spp. and Aspergillus spp. as the most frequent genera. Eight out of 24 Candida spp. isolates were resistant to azole derivatives, out of which four were recovered from wild-harvested prawns. As for production of virulence factors, three (12.5%) and eight (33.3%) isolates presented phospholipase and protease activity, respectively. This is the first comparative study between wild and captive prawns and the first report on yeast microbiota of M. amazonicum. The most relevant finding was the high percentage of resistant Candida spp., including from wild individuals, which suggests the occurrence of an environmental imbalance in the area where these prawns were captured.     

Secretion of β-galactosidases by Aureobasidium pullulans and Penicillium brevicompactum on polygalacturonate medium

An assay has been developed to detect production of extracellular β -galactosidases by fungi during growth on a defined medium containing polygalacturonate. Using this method strains of the yeast-like fungus Aureobasidium pullulans and the filamentous fungus Penicillium brevicompactum which secrete β -galactosidase have been isolated. Seventy strains of yeast were tested but none secrete detectable extracellular β -galactosidase during growth on polygalacturonate agar medium.     

浅部真菌病病原酵母菌构成调查及药敏研究

目的了解本地区浅部真菌病病原酵母菌感染菌种的构成及其耐药性特点,为临床提供病原学诊断和合理使用抗真菌药物的依据。方法采用改良沙氏培养基对1354份临床标本进行酵母菌培养和菌株分离,用科玛嘉念珠菌显色培养基和YBC鉴定卡对所分离的酵母菌进行鉴定,用ROSCO纸片扩散法检测分离菌株对6种常见抗真菌药物的耐药性。结果共分离出10种219株酵母菌,甲真菌病检出率最高(43.80%),其次是股癣(16.70%)、体癣(13.00%)、足癣(11.11%),手癣最低(9.40%)。其中白念珠菌为63.47%;近平滑念珠菌为17.81%;热带念珠菌为6.85%;季也蒙念珠菌为5.94%;无名念珠菌为2.28%,其他酵母菌为3.65%。219株酵母菌对特比萘芬(TBE)、伊曲康唑(ITC)、氟康唑(FLC)、制霉菌素(NYS)、咪康唑(MIC)和酮康唑(KTC)的敏感性分别为53.42%、87.21%、97.26%、100%、80.35%和100%,耐药性分别为20.55%、11.11%、2.28%、0.0、12.72%和0.0。结论本地区浅部真菌病酵母菌感染菌谱以白念珠菌为主,其次是近平滑念珠菌和热带念珠菌,体外药敏显示对制霉菌素、酮康唑和氟康唑有很好的敏感性,对特比萘芬、伊曲康唑和咪康唑产生了较高的耐药性。     

Fungal Communities on Rock Surfaces in Demänovská Ice Cave and Demänovská Cave of Liberty (Slovakia)

This paper is the first geomycological report regarding the fungal communities on rock surfaces in the Demänovská Ice Cave and the Demänovská Cave of Liberty, Slovakia. The samples were collected in June 2014 from five locations from inside both the caves by using sterile swabs wetted with physiological saline (0.85% NaCl). The density of epilithic fungi isolated from the Demänovská Ice Cave ranged from 238.7 to 575.1 CFU (colony-forming units) per m² of the rock surface, and from the Demänovská Cave of Liberty ranged from 88.6 to 347 CFU. Seventeen different free-living culturable fungi (15 filamentous fungi, one yeast, and one yeast-like fungus) were isolated from the rock surfaces of both caves. Generally, Cladosporium cladosporioides and Aspergillus flavus were the most frequently cultured species from the Demänovská Ice Cave and the Demänovská Cave of Liberty, respectively. Free-living fungi found on the rock surfaces of both caves can lead to their slow biodegradation.     

Quantitative and qualitative seasonal changes in the microbial community from the phyllosphere of sugar beet (Beta vulgaris)

Bacteria, yeasts and filamentous fungi colonizing immature, mature and senescing primary leaves of field grown Beta vulgaris (sugar beet) were analysed over a complete growing season. Greatest microbial numbers were detected on senescing primary leaves and these numbers increased over most of the season. The number of colonizers detected on mature leaves was found to be stable over most of the study.Filamentous fungi and yeasts were identified to the genus level and the communities found to have greatest diversity during the summer months. There was no consistent pattern of diversity according to leaf type. Two genera of filamentous fungi, Cladosporium and Alternaria and two yeast genera, Cryptococcus and Sporobolomyces were the most numerous fungal populations isolated. Only 8 filamentous fungi and 3 yeast genera were commonly isolated on PDA (potato dextrose agar).Bacterial strains (1236) were isolated on Tryptic Soy Broth (TSB) agar and identified to species, or in some cases sub-species level, by analysis of their fatty acid methyl ester (FAME) profiles. Isolated bacteria were grouped into 78 named and 37 unnamed species clusters. Greatest number of bacterial species were isolated from young plants and leaves, sampled during the autumn months. Bacterial community diversity was lowest in mid-summer and winter months. Pseudomonas was the most commonly isolated genus and Erwinia herbicola the most common species. P. aureofaciens was the only species isolated from soil that was also isolated from the phyllosphere of B. vulgaris throughout the season.     

Performance of Selective and Differential Media in the Primary Isolation of Yeasts from Different Biological Samples

In view of the increase in yeast infections, especially polymicrobial ones, differential culture media have acquired increasing importance. The present study evaluated the Sabouraud chloramphenicol, Biggy agar, Pagano Levin agar and CHROMagar Candida media in terms of isolation, number of yeast colony forming units per plate, and inhibition of bacteria and filamentous fungi. To this end, we used 223 biological samples, including feces, and oral, vaginal and anal mucosae from 86 patients presenting or not symptoms of fungal infections. The four media did not differ significantly in terms of detection of yeast-positive cultures. The number of colony forming units per plate ranged from zero to 2.380, with a predominance of counts of 1 to 9 colonies per plate. No significant differences were observed among the four culture media in terms of number of colonies counted, for each kind of biological material. Fifteen species belonging to the genera Candida, Saccharomyces, Cryptococcus, Trichosporon and Rhodotorula were isolated, with C. albicans being the predominant species, followed by C. parapsilosis and R. rubra. CHROMagar Candida and Biggy agar were complementary in the isolation of the different species and favored a greater recovery of polymicrobial cultures. Pagano Levin agar isolated the smallest variety of species. Sabouraud chloramphenicol agar was the least effective in terms of bacterial inhibition and favored a greater development of filamentous fungi. The results suggest that more than one culture medium should be used for an adequate primary isolation.     

Association of anurans with pathogenic fungi

In a study of 450 Amazonian anurans, we isolated yeasts and yeast-like fungi from 54 animals (Bufo granulosus, B. marinus, Dendrophrynyscus sp., Hyla geographica, H. lanciformes, Ololygon rubra, Adenomera hylaedactyla, Eleutherodactylus fenestratus, Leptodactylus fuscus, L. ocellatus, L. pentadactylus). The internal organs of these animals did not show any macroscopic anomaly nor histopathology. We recovered 105 fungal isolates from the anuran liver, lung, kidney, spleen, heart and gonad. The isolates were made up of 30 fungal species, 9 of which (48 isolates, 46%) were fungi with known pathogenic potentials, namely: Candida guilliermondii, C. parapsilosis, C. tropicalis, C. glabrata, Geotrichum candidum, Aureobasidium pullulans, Wangiella dermatitidis, Trichosporon cutaneum and Exophiala werneckii. Eleven animals harbored identical fungi in more than one of their internal organs; seven animals had more than one fungal species colonizing a single organ. Our findings indicated probable natural subclinical infections of candidiasis, geotrichosis or phaeohyphomycosis, and also symbiotic presence of non-pathogenic fungi among neotropical anurans.     

Isolation of clinically relevant fungal species from solid waste and environment of dental health services

Aims: This study was undertaken to detect, identify and determine antifungal susceptibility of yeast strains isolated from dental solid waste and to evaluate airborne fungi in the Brazilian dental health care environment and in the waste storage room. Methods and Results: A group of 17 yeast strains were identified by macroscopic and microscopic characteristics, API 20C Aux system and Multiplex PCR. All 104 airborne fungal colonies were identified by macroscopic and microscopic morphology. The CLSI broth microdilution method was utilized as the susceptibility test. Candida parapsilosis was the prevailing yeast species recovered from waste, followed by Rhodotorula glutinis. Three strains of Candida guilliermondii presented minimal inhibitory concentration values considered to be susceptible dose dependent (2 μg ml^?1) to voriconazole. Of all airborne fungal species, 69% were recovered from the waste storage room and 31% were recovered from the clinical/surgical environment. Most of them were identified as Cladosporium spp. Conclusions: These findings reinforce the potential risk of waste handling and point out the need for safe management to minimize the spread of these agents to the environment. Filamentous fungi isolation in almost all sampled environments indicates that a periodic monitoring of airborne microbiota in the dental health care service environment is required. Significance and Impact of the Study: The survival of yeast strains for 48 h suggests that dental waste should be carefully controlled and monitored.     

Rapid identification of medically important yeasts by electrophoretic protein patterns

A simple electrophoretic method for yeast identification was evaluated. Whole cells were extracted by SDS and the protein profiles obtained in SDS-PAGE after Coomassie blue staining were compared for 52 strains from 9 species of yeast or yeast-like fungi commonly isolated from man (Candida albicans, C. glabrata, C. guilliermondii, C. krusei, C. parapsilosis, C. pseudotropicalis, C. tropicalis, Geotrichum candidum, Saccharomyces cerevisiae). The corresponding patterns showed 30 to 45 polypeptides in the range 95-20 kDa and were clearly different for the 9 species. No differences could be detected between strains from the same species. The characteristic patterns were obtained within 24 h allowing rapid identification of the most commonly encountered clinical yeast isolates.     

Yeasts and filamentous fungi carried by the gynes of leaf-cutting ants

Insect-associated microbes exhibit a wide range of interactions with their hosts. One example of such interactions is the insect-driven dispersal of microorganisms, which plays an essential role in the ecology of several microbes. To study dispersal of microorganisms by leaf-cutting ants (Formicidae: Attini), we applied culture-dependent methods to identify the filamentous fungi and yeasts found in two different body parts of leaf-cutting ant gynes: the exoskeleton and the infrabuccal pocket. The gynes use the latter structure to store a pellet of the ants’ symbiotic fungus during nest founding. Many filamentous fungi (n = 142) and yeasts (n = 19) were isolated from the gynes’ exoskeleton. In contrast, only seven filamentous fungi and three yeasts isolates were recovered from the infrabuccal pellets, suggesting an efficient mechanism utilized by the gynes to prevent contamination of the symbiotic fungus inoculum. The genus Cladosporium prevailed (78%) among filamentous fungi whereas Aureobasidium, Candida and Cryptococcus prevailed among yeasts associated with gynes. Interestingly, Escovopsis, a specialized fungal pathogen of the leaf-cutting ant-fungus symbiosis, was not isolated from the body parts or from infrabuccal pellets of any gynes sampled. Our results suggest that gynes of the leaf-cutter ants Atta laevigata and A. capiguara do not vertically transmit any particular species of yeasts or filamentous fungi during the foundation of a new nest. Instead, fungi found in association with gynes have a cosmopolitan distribution, suggesting they are probably acquired from the environment and passively dispersed during nest foundation. The possible role of these fungi for the attine ant–microbial symbiosis is discussed.     

Drug sensitivity of Candida in patients with kidney diseases receiving immunosuppressive therapy

It was shown that prednisolone and its combination with azathioprine++ increased contamination of the patients with yeast-like fungi and promoted development of candidiasis in them to a greater extent than cyclophosphamide. In the patients treated with the immunodepressants there was observed a carrier state in regard to various yeast-like fungi: 12 species belonging to 6 genera were isolated from the pathological materials. Determination of sensitivity to antifungal drugs in 200 Candida strains revealed that amphotericin B was the most active agent. Then followed mycoheptin, nystatin and nitroxolin. Levorin was the least active drug. The MICs of the drugs for the majority of the cultures were 0.5, 4-8, 8-16 and 32-64 micrograms/ml respectively. Candida resistant strains (mainly to levorin and mycoheptin) were isolated only from recipients of kidney transplants during the early postoperative period when the patients were subjected to intensive immunodepressive and prophylactic antifungal therapy. Among the fungi of the Candida genus C. guillermondii and C. parapsilosis proved to be the most resistant. Under the hospital conditions and in vitro studies it was found that cyclophosphamide and combinations of prednisolone with cytostatics increased resistance of Candida to the antifungal drugs. Rapid increasing of the fungi resistance to levorin and mycoheptin was observed. The increase in the resistance to amphotericin B was somewhat lower and that to nitroxolin and nystatin was extremely low. The study of the combined effect of the immunodepressants and antifungal drugs demonstrated that the immunodepressants increased the antifungal activity of amphotericin B, levorin and nitroxolin.(ABSTRACT TRUNCATED AT 250 WORDS)     

临床标本中酵母样真菌的分离鉴定和药敏结果分析

目的调查目前临床标本中酵母样真菌感染现状及耐药性情况。方法常规分离临床标本中的酵母样真菌,用科玛嘉显色培养基及法国生物-梅里埃API20CAUX鉴定系统鉴定菌种,并用K—B法进行药敏试验。结果研究期间共分离到193例有临床意义的酵母样真菌,检出率较高的依次为白假丝酵母菌（62．7％）,热带假丝酵母菌（20．2％）,光滑球拟酵母菌（9．3％）。在6种抗真菌药中,对伊曲康唑、氟康唑的耐药率增高。结论近年来由酵母样真菌感染引起的疾病及其对常用抗真菌药物的耐药率有明显增加,应加强真菌的检测和耐药性监测工作,以指导临床合理使用药物。     

粤北一种虫草分离菌的抗酵母现象

CR 95 1 2是一株分离自粤北一种虫草的无孢丝状真菌 ,经培养初步鉴定为无孢菌目(^{Agonomycetales})的丝核菌属 (^Rhizoctonia)。对包括革兰氏阳性及阴性细菌、放线菌、丝状真菌和酵母菌在内的 2 6株致敏菌株的抗性测定表明 ,CR 95 1 2对包括红酵母属 (^Rhodotorula)、酵母属 (^{Saccharomyces})、毕赤氏酵母属 (Pichia)和隐球酵母属 (^Cryptoc     

Culturable Fungi of Stored ‘Golden Delicious’ Apple Fruits: A One-Season Comparison Study of Organic and Integrated Production Systems in Switzerland

The effects of organic and integrated production systems on the culturable fungal microflora of stored apple fruits from five matched pairs of certified organic and integrated ‘Golden Delicious’ farms were studied at five representative production sites in Switzerland. Isolated fungi were identified morphologically. Colonization frequency (percentage of apples colonized), abundance (colony numbers), and diversity (taxon richness) were assessed for each orchard. The standard quality of the stored fruits was comparable for both organic and integrated apples and complied with national food hygiene standards. Yeasts (six taxa) and the yeast-like fungus Aureobasidium pullulans were the dominant epiphytes, filamentous fungi (21 taxa) the dominant endophytes. The most common fungi occurred at all sites and belonged to the “white” and “pink” yeasts, yeast-like A. pullulans, filamentous fungi Cladosporium spp., Alternaria spp., and sterile filamentous fungi. Canonical correspondence analysis of the total fungal community revealed a clear differentiation among production systems and sites. Compared to integrated apples, organic apples had significantly higher frequencies of filamentous fungi, abundance of total fungi, and taxon diversity. The effects of the production system on the fungal microflora are most likely due to the different plant protection strategies. The incidence of potential mycotoxin producers such as Penicillium and Alternaria species was not different between production systems. We suggest that higher fungal diversity may generally be associated with organic production and may increase the level of beneficial and antagonistically acting species known for their potential to suppress apple pathogens, which may be an advantage to organic apples, e.g., in respect to natural disease control.     

Antifungal Activity of <Emphasis Type="Italic">Pv</Emphasis>D1 Defensin Involves Plasma Membrane Permeabilization,Inhibition of Medium Acidification,and Induction of ROS in Fungi Cells

In recent years, studies have demonstrated the function of many antimicrobial peptides against an extensive number of microorganisms that have been isolated from different plant species and that have been used as models for the study of various cellular processes linked to these peptides’ activities. Recently, a new defensin from Phaseolus vulgaris (L.) seeds, named PvD_1, was isolated and characterized. PvD₁ was purified through anion exchange and phase-reverse chromatography. PvD₁’s antifungal activity was tested. A SYTOX Green uptake assay revealed that the defensin PvD₁ is capable of causing membrane permeabilization in the filamentous fungi Fusarium oxysporum, Fusarium solani, and Fusarium laterithium and in yeast strains Candida parapsilosis, Pichia membranifaciens, Candida tropicalis, Candida albicans, Kluyveromyces marxiannus, and Saccharomyces cerevisiae at a concentration of 100 μg/ml. Ultrastructural analysis of C. albicans and C. guilliermondii cells treated with this defensin revealed disorganization of both cytoplasmic content and the plasma membrane. PvD₁ is also able to inhibit glucose-stimulated acidification of the medium by yeast cells and filamentous fungi, as well as to induce the production of reactive oxygen species and nitric oxide in C. albicans and F. oxysporum cells.     

Aerobic microorganisms associated with alfalfa leafcutter bees (megachile rotundata)

Characterization of microorganisms associated with alfalfa leaf-cutter bee (Megachile rotundata) nectar, pollen, provisions, larval guts, and frass (excreta) in Alberta demonstrated a varied aerobic microflora. Yeasts were isolated frequently from nectar, pollen, and provisions but rarely from guts or frass. The most prevalent yeast taxa were: Candida bombicola, Cryptococcus albidus, Metschnikowia reukaufii, and Rhodotorula glutinis. Although few filamentous fungi were found in nectar, they were frequently isolated from pollen and provisions; the predominant taxa were Alternaria alternata, Cladosporium cladosporioides, C. herbarum, Epicoccum nigrum, and Penicillium chrysogenum. Bacteria, including species of Bacillus, Corynebacterium, Micrococcus, and the actinomycete Streptomyces, also were prevalent in provisions and/or on pollen. In general, the diversity of microorganisms isolated from alimentary canals and frass was lower than from nectar, pollen, and provisions. Bacillus firmus, B. licheniformis, B. megaterium, B. pumilus, and Streptomyces spp. were the most frequently isolated bacteria, whereas Trichosporonoides megachiliensis was the most common filamentous fungus isolated from larval guts and/or frass. These taxa may be part of the resident microflora of the alimentary canal. Populations of bacteria and filamentous fungi, but not yeasts, were larger from Ascosphaera aggregata-infected larvae than from healthy larvae. However, with the exception of Aspergillus niger and T. megachiliensis in frass from healthy larvae, no taxon of filamentous fungi was conspicuously present or absent in infected larvae, healthy larvae, or their frass. Offprint reauests to: M.S. Goettel.     

Keratinophilic fungi isolated from the air at Pavia

The presence of keratinophilic fungi was revealed by sampling the air of Pavia (Italy) from March 1981 to February 1982. The species isolated were: Chrysosporium indicum, Geomyces pannorum var.pannorum, Microsporum gypseum, Myceliophtora vellerea and Trichophyton terrestre. Several filamentous fungi tolerating high levels of cycloheximide were also recovered.     

Comparison of morphogenetic networks of filamentous fungi and yeast.

Fungi generally display either of two growth modes, yeast-like or filamentous, whereas dimorphic fungi, upon environmental stimuli, are able to switch between the yeast-like and the filamentous growth mode. Signal transduction pathways have been elucidated in the budding yeast Saccharomyces cerevisiae, establishing a morphogenetic network that links cell-cycle events with cellular morphogenesis. Recent molecular genetic studies in several filamentous fungal model systems revealed key components required for distinct steps from fungal spore germination to the maintenance of polar hyphal growth, mycelium formation, and nuclear division. This allows a mechanistic comparison of yeast-like and hyphal growth and the establishment of a core model morphogenetic network for filamentous growth including signaling via the cAMP pathway, Rho modules, and cell cycle kinases. Appreciating similarities between morphogenetic networks of the unicellular yeasts and the multicellular filamentous fungi will open new research directions, help in isolating the central network components, and ultimately pave the way to elucidate the central differences (of many) that distinguish, e.g., the growth mode of filamentous fungi from that of their yeast-like relatives, the role of cAMP signaling, and nuclear division.