Antifungal activity ofBullera alba (Hanna) Derx

A strain ofBullera alba that secretes a killer toxin inhibitory (at pH values ranging from 3 to 7) to many ascomycetous and basidiomycetous yeast-like fungi was discovered. Its killer phenotype was incurable. The toxin was relatively thermostable and resistant to many proteases, and it was identified as a microcin. It inhibited the growth of some pathogenic yeasts and was the most active againstCryptococcus neoformans.     

Realization pathways of prolactin modulating effect on the cAMP-dependent mechanism of meiosis regulation in bovine oocytes

Cyclic AMP is one of the key regulators of mammalian meiosis. In the present work, realization pathways of the previously revealed modulating effect of prolactin (PRL) on the cAMP-dependent mechanism of meiosis regulation in bovine oocytes were studied. A comparative investigation of individual and combined effects of PRL (50 ng/ml) and an activator of adenylate cyclase forskolin (FK, 20 μM) on the meiotic reinitiation and completion of nuclear maturation in cumulus-surrounded and cumulus-free oocytes was performed. It has been shown that the pattern of the effects of PRL on the meiotic resumption in oocytes devoid of cumulus cells depends on the presence of FK in the culture medium. Furthermore, the realization of this effect is not associated with the activation of cytoplasmic isoforms of protein kinase C. It has also been found that PRL inhibits the retarding action of FK on the completion of oocyte nuclear maturation both in the presence and absence of cumulus cells. These findings suggest that PRL may modulate the functioning of the cAMP-dependent mechanism of meiosis regulation by the direct action on bovine oocytes, with realization of this action being independent of the metabolic coupling of oocytes with cumulus cells.     

Characterization of mycocin secreted by <Emphasis Type="Italic">Rhodotorula colostri</Emphasis> (Castelli) Lodder

A Rhodotorula colostri strain has been isolated that shows fungicidal activity against related species of the genera Rhodosporidium, Sporidiobolus, and their anamorphs phylogenetically belonging to the order Sporidiobolales (Microbotryomycetes, Pucciniomycotina). The agent secreted has a molecular weight of about 4–5 kDa, is active at pH values ranging from 3.5 to 5.5, and is thermolabile and protease-sensitive.     

Comprehensive proteomic analysis of human cervical-vaginal fluid using colposcopy samples

Background  

Cervical-vaginal fluid (CVF) plays an important role in the prevention of gynecological infections, although little is known about the contribution of CVF proteins to the immunity of the lower female genital tract. In order to analyze the protein composition of human CVF, we used CVF samples that are routinely collected during colposcopy, but are usually discarded. Since these samples are available in large quantities we aimed to analyze their usefulness for proteomics experiments. The samples were analyzed using different prefractionation techniques (ultrafiltration and C₄(RP)-LC protein separation) followed by C₁₈(RP)-LC peptide separation and identification by MALDI-TOF-TOF mass spectrometry. To determine the reproducibility of this proteomics platform we analyzed three technical replicates. Using spectral counting, protein abundances were estimated in a semiquantitative way. We also compared the results obtained in this study with those from previous studies derived from patients with different physiological conditions in order to determine an overlapping protein set.     

Peroxidases from alfalfa roots: Catalytic properties and participation in degradation of polycyclic aromatic hydrocarbons

From the roots and root exudates of 3-week-old plants of alfalfa (Medicago sativa L.), anionic and cationic peroxidases differing in principal physicochemical and catalytic properties were isolated and purified. Main features of anionic peroxidases detected in the roots and root exudates were identical. Phenanthrene present in the soil used for alfalfa growing influenced the number of forms and activity of peroxidases in crude enzyme preparations but did not affect the properties of pure enzymes. In the presence of a synthetic mediator, purified peroxidases can oxidize phenanthrene and its derivatives, including potential microbial metabolites of polycyclic aromatic hydrocarbons (PAH). The fact that the enzymes excreted in root exudates in a purified form can oxidase PAH proves their participation in degradation of PAH and their microbial metabolites in alfalfa rhizosphere. These new data indicate that the processes of plant and microbial degradation of pollutants in the rhizosphere are coupled; they are relevant to understanding the molecular mechanisms of degradation of persistent pollutants by plant-microbial complexes.     

Finding the best antibody dilution by repeated immunostaining of the same tissue section

One can find the optimal antibody dilution for immunostaining by repeated staining on the same tissue section by using a less dilute antibody for each attempt. Using secondary antibody and horseradish peroxidase conjugated to a dextran polymer, a section stained repeatedly with several dilutions of antibody appears as good as a section stained with only the last dilution.     

Isolation of tremelloid yeasts on glucuronate medium

D-Glucuronate-containing agar is suggested for evaluating the population density and diversity of tremelloid yeasts in natural cenoses. This medium is superior to the commonly used wort agar on which many representatives of tremelloid yeasts cannot be revealed.