PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Geotrichum”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 19 recordsLinked to original sources
PubMed2005

Three new asexual arthroconidial yeasts, Geotrichum carabidarum sp. nov., Geotrichum histeridarum sp. nov., and Geotrichum cucujoidarum sp. nov., isolated from the gut of insects.

Twenty arthroconidial yeasts were isolated from the digestive tract of basidiome-feeding beetles and lepidopteran larvae. All of the yeasts reproduced only asexually by arthroconidia and some by endo- or blastoconidia as well. Based on the comparisons of sequences in ribosomal RNA genes and other taxonomic characteristics, the yeasts were identified as three unknown Geotrichum species. The three new species are described as Geotrichum carabidarum (NRRL Y-27727T), G. histeridarum (NRRL Y-27729T), and G. cucujoidarum (NRRL Y-27731T). Phylogenetic analyses from ribosomal DNA sequences showed that members of the genus Geotrichum and related arthroconidial yeast taxa were divided into two major clades: (1) Dipodascus and Galactomyces with Geotrichum anamorphs including all the new species; and (2) Magnusiomyces with Saprochaete anamorphs. G. cucujoidarum formed a subclade with G. fermentans and Geotrichum sp. Y-5419, while the two closely related species, G. carabidarum and G. histeridarum, represent a new basal subclade in the clade of Geotrichum and its teleomorphs.

Animals↗
PubMed2005

Geotrichum silvicola sp. nov., a novel asexual arthroconidial yeast species related to the genus Galactomyces.

Four strains of an asexual arthroconidial yeast species were isolated from Drosophila flies in two Atlantic rain forest sites in Brazil and two strains from oak tasar silkworm larvae (Antheraea proylei) in India. Analysis of the sequences of the D1/D2 large subunit rRNA gene showed that this yeast represented a novel species of the genus Geotrichum, described as Geotrichum silvicola sp. nov. The novel species was related to the ascogenous genus Galactomyces. The closest relatives of Geotrichum silvicola were Galactomyces sp. strain NRRL Y-6418 and Galactomyces geotrichum. The type culture of Geotrichum silvicola is UFMG-354-2T (=CBS 9194T=NRRL Y-27641T).

Animals↗
PubMed1995

Molecular characterization of a Galactomyces geotrichum lipase, another member of the cholinesterase/lipase family.

Geotrichum candidum secretes several lipase isoenzymes, differing in their selectively towards esters of long chain fatty acids with a cis-9 double bond. One group shows an absolute selectively towards these fatty acid esters, the other group has a more relaxed specificity and will also hydrolyze other long chain fatty acid esters. Galactomyces geotrichum secrets a lipase that has the same specificity as the latter group. The corresponding lipase gene was cloned from Galactomyces geotrichum. From an alignment of our enzymes' primary structure with those of different strains of Geotrichum candidum, remarkable conservation is evident and it is not yet possible to identify residues/structures responsible for differences in fatty acid specificity. Comparison of the GCL/GGL family with a variety of lipases from other sources, indicated that they are more related to mammalian than microbial lipases.

Amino Acid Sequence↗
PubMed1976

Isolation of fungi belonging to the genera Geotrichum and Trichosporum from human dermal lesions.

Isolates of Geotrichum and Trichosporum spp. obtained from patients with a variety of dermal lesions were studied. Among 2,202 cases examined, microorganisms of these genera were recovered from 100 (4,5%); there were 38 isolated of Geotrichum- and 62 of Trichosporum- spp. Most isolations were obtained from nails: 52 cases. The species most frequently found were T. beigelii (25 cases) and G. candidum (30 cases). In 50 of the patients, these fungi were isolated in pure culture, in an additional 40 Trichosporum spp. were found. Mixed cultures with C. albicans were observed in 28 patients, with other Candida spp. in 16 and with dermatophytes in 6. Among the patients whose isolations occurred in pure cultures, the number of colonies recovered was large in 20 cases, 1 with Geotrichum candidum - 19 with Trichosporum (16 T. beigelii, 3 T. capitatum). The relationship between the isolated yeast-like fungi and the dermal lesion was considered to be direct in these 20 patients.

Candida↗
PubMed2000

Re-examination of some species of the genus Geotrichum Link: Fr.

The nutritional physiology and the growth rate of thirty-four strains representing species of Geotrichum without known teleomorph states were examined. From twenty-seven strains the mol% G+C were calculated from the DNA melting curves. The first derivatives of the melting curves of seven strains, including the type strain of Geotrichum clavatum, demonstrated the presence of two peaks, 12% away from each other; the remaining strains showed only a single broad peak. DNA homology values among strains of the former group were high, indicating their conspecificity. The strains of the latter group could be subdivided into six DNA homology groups, four of which could be identified with recognized species and two may represent novel taxa. A combined key of Geotrichum and its teleomorph states Galactomyces and Dipodascus is presented.

Base Composition↗
PubMed2006

Geotrichum vulgare sp. nov., a novel asexual arthroconidial yeast.

Two strains of a novel yeast species were isolated from different habitats, from soil in an alluvial zone national park in Austria and from a drain in a Turkish soft drinks factory. Analysis of the nucleotide sequences of the D1/D2 region of their large-subunit rDNAs and PCR fingerprints show that the strains are members of the same species, described as Geotrichum vulgare sp. nov. Analysis of nucleotide sequences showed that this species is related to the ascogenous genus Galactomyces. The closest phylogenetic relative is Geotrichum silvicola, a recently described species. The type strain of Geotrichum vulgare is HA1379T (= CBS 10073T = NRRL Y-27915T).

Austria↗
PubMed1998

Isolation and identification of Geotrichum candidum as an etiologic agent of geotrichosis in Bulgaria.

Geotrichosis affects mainly patients with systemic diseases like diabetes mellitus, leukoses, neoplasms etc. Clinically, it is similar to candidiasis and may occur as an oral, vaginal, skin, or systemic infection. Clinical specimens (98 sputa and 67 oral smears) were collected and studied using microscopic examination of Gram stained preparations and culture sampling between 1995 and 1997. Geotrichum candidum was isolated as a single pathogen in 8 sputum and 7 oral smear samples. Ten-day antifungal treatment with Nizoral was applied and resulted in relatively quick clinical improvement. The presented cases are the first cases of pulmonary and oral infections reported in our home practice in which Geotrichum candidum species was identified as a pathogen. The identification of Geotrichum candidum using combination of colonial and microscopic morphologic features increase the possibilities for diagnostic decision.

Bulgaria↗
PubMed1998

[Geotrichum capitatum infection in a neutropenic patient. Apropos of a case and review of the literature].

INTRODUCTION: Geotrichum capitatum sepsis are rare, occurring exclusively in immunocompromised patients. EXEGESIS: We report the case of a patient with acute leukemia, presenting with chemotherapy-induced neutropenia and hospitalized in an intensive care unit for a severe sepsis. In spite of an antibiotic and antifungal treatment, the patient died of cardiorespiratory failure. Later on, blood cultures proved to be positive for Geotrichum capitatum. CONCLUSION: If fungal infections are common in neutropenic patients, Geotrichum capitatum sepsis remain exceptional. The portal of entry is digestive or respiratory, and the invasion is favored by immunodepression and suppression of the normal microbial flora. Induced lesions can be multiorganic. The treatment is not well established, and the association of either amphotericine B and 5-fluorocytosine or amphotericine B and itraconazole would lead to better results. Nevertheless, the prognosis is still unfavorable, with a mortality rate of approximately 75%.

Acute Disease↗
PubMed2001

Molecular differentiation of sibling species in the Galactomyces geotrichum complex.

PCR-analysis, multilocus enzyme electrophoresis and molecular karyotyping were used to characterize 52 strains belonging to the genus Galactomyces. The resultant data revealed that a PCR method employing the universal primer N21 and microsatellite primer (CAC)5 is appropriate for the distinction of four Ga. geotrichum sibling species, Ga. citri-aurantii and Ga. reessii. Better separation was achieved with the UP primer N21; each species displayed a specific pattern with very low intraspecific variation. We propose to use the primer N21 for the differentiation of the six taxa composing the genus Galactomyces. Multilocus enzyme electrophoresis revealed genetic homogeneity of each sibling species within the Ga. geotrichum complex. On the other hand, the four sibling species, having from 41 to 59% of nDNA homology and similar phenotypic characteristics, are clearly distinguished based on their electrophoretic profiles using two enzymes: mannose-6-phosphate isomerase (MPI) and phosphoglucomutase (PGM). Despite the same number of chromosomal bands, different karyotype patterns were found in Ga. geotrichum sensu stricto and its two sibling species A and B. Within each sibling species, chromosome length polymorphism was observed, in particular for small bands, allowing discrimination to the strain level.

DNA Fingerprinting↗
PubMed1989

Disseminated Geotrichum capitatum infection in a patient with acute myeloid leukemia.

A case of invasive Geotrichum capitatum infection is reported; a young patient had an acute leukemia for which he received a chemotherapy, and presented sepsis with blood cultures for Geotrichum capitatum, namely Dipodascus spicifer; this pathogen only described in cactus rot, is responsible for the first case of a human disseminated infection reported in literature. Then he developed a splenic and epididymic infection, with positive cultures for Geotrichum capitatum after splenectomy and castration. Treatment with amphotericin B and itraconazole was started with low minimal inhibitory concentration (0.1 microgram/ml). The patient died of massive hemoptisis. Autopsy findings demonstrated a lung, brain and kidneys seeding.

Adult↗
PubMed1991

Characterization of two beta-tubulin genes from Geotrichum candidum.

The beta-tubulin genes G beta 1 and G beta 2 from the phytopathogenic hemiascomycete Geotrichum candidum were found to be highly diverged in amino acid sequence from those of other filamentous fungi. G beta 1 and G beta 2 were also divergent from each other, with the coding regions sharing only 66% nucleotide sequence homology and 64% amino acid identity. However, the proteins shared 82% similarity and only 25 of the 161 non-identical amino acid substitutions were non-conservative. The organization of G beta 1 is similar to other fungal beta-tubulin genes, but G beta 2 has several unusual features; it has 2 amino acid additions in the N-terminal 40 residues and must employ an uncommon 5' splice junction sequence in preference to an overlapping perfect consensus. The amino acid change found to confer benomyl resistance in Neurospora crassa was also present in G beta 2. G beta 1 has four introns which are located similarly to those of beta-tubulin genes in other fungi. G beta 2, however, has a single intron in a unique location. Translational fusions employing the 5' non-coding regions of the two Geotrichum beta-tubulin genes were made with the hygromycin phosphotransferase gene and shown to function in Schizosaccharomyces pombe and Trichoderma hamatum. However, G. candidum could not be transformed with these or other tested plasmids commonly used for fungal transformation.

Amino Acid Sequence↗
PubMed1979

Carbohydrate composition and taxonomy of Geotrichum, Trichosporon and allied genera.

The yeast-like genera Geotrichum and Trichosporon are heterogeneous and are related with anamorphs of both ascomycetous and basidiomycetous fungi. A rearrangement can be obtained using carbohydrate composition of intact cells, studied with the aid of gas-liquid chromatography. The genus Geotrichum is restricted to ascomycetous species with a dominance of galactomannans, whereas Trichosporon is reserved for basidiomycete-like, xylose-containing species. Consequently, some new combinations are introduced in both genera. Representatives of related genera are included for comparison: e.g. Dipodascus, Hyphophichia, Cryptococcus and Filobasidium.

Carbohydrates↗
PubMed2004

A thermostable lipase produced by a newly isolated Geotrichum-like strain, R59.

Growth and production of lipase by a new Geotrichum-like strain, R59, were studied. Production of extracellular lipase was substantially enhanced when the initial pH of the culture medium, types of carbon and nitrogen sources, substances probably stimulating the lipase biosynthesis, the temperature, and time of growth were optimized. Sucrose and triolein were the most effective carbon sources for lipase production. Maximum lipase activity (146 U/ml(-1)) was obtained with urea as the nitrogen source. Growth at 30 degrees C, an initial pH of 6.0 and incubation time of 48 h were found as optimum conditions for cell growth and production of lipase by Geotrichum-like strain R59. The enzyme was thermostable and exhibited very high activity after 1 h incubation at 60 degrees C.

Carbon↗
PubMed1992

Substrate specificities of lipases A and B from Geotrichum candidum CMICC 335426.

The mould Geotrichum candidum produces extracellular lipases with different substrate specificities according to strains. We purified two lipases - termed lipase A and lipase B - from Geotrichum candidum CMICC 335426. The specificity of the two lipases was investigated using hydrolysis assays on emulsions of pure acylglycerols and a wide range of fatty acid esters. Lipase B was very highly specific for hydrolysis of esters of cis-delta 9-fatty acids. Lipase A did not show such strict specificity, because it hydrolysed a wider variety of fatty acid esters, in particular those of palmitic acid and isomers of oleic acid. We think that differences in specificity previously observed for crude lipases from various strains of G. candidum can be explained by the presence of different levels of specific (lipase B) and non-specific (lipase A) lipases. As lipases A and B are structurally related proteins, a minor variation in structure may be responsible for the differing specificities.

Chromatography, Liquid↗
PubMed2004

Optimization of extracellular lipase production by Geotrichum sp. using factorial design.

Response surface methodology was employed to study the effects of carbon source (soy oil, olive oil and glucose) and nitrogen source concentrations (corn steep liquor and NH(4)NO(3)) on the lipase production by Geotrichum sp. The experiment included a 2(4) central composite rotatable design (CCRD) and four others 2(3) CCRD. According to the responses from the experimental designs, the effects of each variable were calculated and the interactions between them were determined. The response surface methodology was applied for the optimization of the nutrient concentrations in the culture medium for the enzyme production, at 30 degrees C. The optimum medium composition for lipase production by Geotrichum sp. was ammonium nitrate 2.1-2.5%, corn steep liquor 13-15% and soy oil 0.6% as carbon source, which lead to a lipase activity of about 20 U/ml. Using olive oil as carbon source, the optimum composition was ammonium nitrate 0.8-1%, corn steep liquor 13-15% and olive oil 0.6%, leading to an activity of 17 U/ml.

Analysis of Variance↗