Search results for "FUNGAL"

Glucose uptake in germinating Aspergillus nidulans conidia: involvement of the creA and sorA genes

2003

d-Glucose uptake in germinating wild-typeAspergillus nidulansconidia is an energy-requiring process mediated by at least two transport systems of differing affinities for glucose: a low-affinity system (Km∼1·4 mM) and a high-affinity system (Km∼16 μM). The low-affinity system is inducible by glucose; the high-affinity system is subject to glucose repression effected by the carbon catabolite repressor CreA and is absent insorA3mutant conidia, which exhibit resistance tol-sorbose toxicity. An intermediate-affinity system (Km∼400 μM) is present insorA3conidia germinating in derepressing conditions.creAderepressed mutants show enhanced sensitivity tol-sorbose. The high-affinity uptake system ap…

A method for taxonomic determination ofCandida albicans with DNA probes

1993

Determination of Candida species represents an important problem derived from the clinical implications of the species belonging to this genus. DNA probes have already been used for the epidemiology of Candida albicans, as well as for taxonomic analysis of Candida and other genera, although these probes are based on non-species-specific DNA sequences. In this work we carried out a 48-h assay, allowing the identification of C. albicans from clinical isolates, using DNA probes based on C. albicans LEU2 and URA3 genes. Another probe related to C. albicans SEC18 gene was shown not to be C. albicans specific.

The taxonomic position of Roesleria subterranea

2006

The genus Roesleria was introduced with the single species Roesleria hypogaea (current name: R. subterranea) by Thümen in 1877. The species was originally described from roots of grapevine and recognised as a facultative root-rotting parasite. The mazaediate ascoma with evanescent asci led to the assumption that Roesleria would be an ally of mazaediate lichens. In this study we calculate 28S, 18S as well ITS1-5.8S-ITS2 rDNA phylogenies. These data indicate that Roesleria is closely related to Hymenoscyphus (Helotiales). In contrast to other members of the Helotiales, the ascospores of Roesleria are passively released, and a distinct apical apparatus cannot be observed by LM. Electron optic …

Distributions of the growth rate of the germ tubes and germination time of Penicillium chrysogenum conidia depend on water activity

2008

The effects of water activities for sporulation (a(wsp)) and germination (a(wge)) on the distributions of the growth rate of the germ tubes (mu) and the germination time (t(G)) of Penicillium chrysogenum conidia were determined by monitoring the length of the same germ tubes throughout the experiments automatically. No relationship between the individual t(G)'s and mu's could be established. Irrespective of the water activity for germination, mu was greater and t(G) was less for conidia produced at 0.95a(wsp) than that at 0.99a(wsp). At 0.99 a(wge) the mean and the standard deviation of t(G) were smaller than those obtained at 0.95a(wge). At 0.99a(wge), normal distributions for mu and t(G) …

Lag time for germination of Penicillium chrysogenum conidia is induced by temperature shifts.

2013

In the environment, fungal conidia are subject to transient conditions. In particular, temperature is varying according to day/night periods. All predictive models for germination assume that fungal spores can adapt instantaneously to changes of temperature. The only study that supports this assumption (Gougouli and Koutsoumanis, 2012, Modelling germination of fungal spores at constant and fluctuating temperature conditions. International Journal of Food Microbiology, 152: 153-161) was carried out on Penicillium expansum and Aspergillus niger conidia that, in most cases, already produced germ tubes. In contrast, the present study focuses on temperature shifts applied during the first stages…

The Candida albicans cell wall-associated glyceraldehyde-3-phosphate dehydrogenase activity increases in response to starvation and temperature upshi…

2002

We have determined the effect of environmental factors (mild thermal upshift and starvation) on the Candida albicans cell wall-associated glyceraldehyde-3-phosphate dehydrogenase (cwGAPDH) activity. Temperature upshift (from 28 to 37 degrees C) and/ or starvation (at 28 or 37 degrees C in water) of exponentially growing yeast cells caused an increase in cwGAPDH activity (3 to 5-, and 7 to 8-fold, respectively). This increase in activity did not correlate with an increase in the amount of cwGAPDH protein present, as determined by flow cytometry, immunoelectron microscopy and Western-blotting. These results indicate that thermal upshift and starvation cause an activation of the cwGAPDH in C. …

A review of the biological and pharmacological activities of saponins.

1996

Summary This paper reviews the important biological and pharmacological activities of saponins reported over the last few years. These include cancer-related activity, as well as antiphlogistic and antiallergic, immunomodulating, antihepatotoxic, antiviral, hypoglycemic, antifungal and molluscicidal activities. The action of saponins on the cardiovascular, central nervous, and endocrine systems and other miscellaneous effects are also discussed.

CTAB‐PLGA Curcumin Nanoparticles: Preparation, Biophysical Characterization and Their Enhanced Antifungal Activity against Phytopathogenic Fungus Pyt…

2020

Bioactive saponins with cancer related and immunomodulatory activity: Recent developments

2005

Abstract Saponins are natural glycosides of steroid or triterpene which exhibited many different biological and pharmacological actions: e.g. immunomodulatory, antitumor, antiinflammatory, molluscicidal, antiviral, antifungal, hypoglycemic, hypocholesterolemic, to mention just a few. The aim of this summarize recent advances on the bioactivity of saponins related to cancer and immune system, which has attracted a great attention during the last five years

ERA-experiment “space biochemistry”

1995

Abstract The general goal of the experiment was to study the response of anhydrobiotic (metabolically dormant) microorganisms (spores of Bacillus subtilis, cells of Deinococcus radiodurans, conidia of Aspergillus species) and cellular constituents (plasmid DNA, proteins, purple membranes, amino acids, urea) to the extremely dehydrating conditions of open space, in some cases in combination with irradiation by solar UV-light. Methods of investigation included viability tests, analysis of DNA damages (strand breaks, DNA-protein cross-links) and analysis of chemical effects by spectroscopic, electrophoretic and chromatographic methods. The decrease in viability of the microorganisms was as exp…