Epiphytic Yeasts from South Romania for Preventing Food Microbial Contamination.

Epiphytic yeasts represent an important source for the development of novel strategies aiming to combat food microbial contamination. The present study deals with the characterization of nine yeast strains belonging to , , , , and genera, isolated from the surface of plants from the Botanical Garden "Dimitrie Brandza" (Bucharest, Romania) for use as antimicrobial and probiotic agents. The tests involved the determination of the safe status, cell growth under stress conditions, and activity against pathogenic and bacteria strains, respectively, as well as phytopathogenic filamentous fungi and lipolytic activity.

Phenotypic and Genotypic Characterization of Resistance and Virulence Markers in spp. Isolated from Community-Acquired Infections in Bucharest, and the Impact of AgNPs on the Highly Resistant Isolates.

Background: This study aimed to determine, at the phenotypic and molecular levels, resistance and virulence markers in spp. isolated from community-acquired infections in Bucharest outpatients during 2021, and to demonstrate the efficiency of alternative solutions against them based on silver nanoparticles (AgNPs).

Methods: A total of 62 spp.

Molecular Basis of Yeasts Antimicrobial Activity-Developing Innovative Strategies for Biomedicine and Biocontrol.

In the context of the growing concern regarding the appearance and spread of emerging pathogens with high resistance to chemically synthetized biocides, the development of new agents for crops and human protection has become an emergency. In this context, the yeasts present a huge potential as eco-friendly agents due to their widespread nature in various habitats and to their wide range of antagonistic mechanisms. The present review focuses on some of the major yeast antimicrobial mechanisms, their molecular basis and practical applications in biocontrol and biomedicine.

Molecular and Physiological Diversity of Indigenous Yeasts Isolated from Spontaneously Fermented Wine Wort from Ilfov County, Romania.

(1) Background: Wine yeast research offers the possibility of isolating new strains with distinct metabolic properties due to the geographical location of the vineyard and the processes used in winemaking. Our study deals with the isolation and identification of six yeasts from spontaneously fermented wine wort from Romania and their characterization as new potential starter culture for traditional beverages, for food industry or biomedicine. (2) Materials and methods: The isolates were identified using conventional taxonomy tests, phenotypic phylogeny analysis (Biolog YT), MALDI-TOF mass spectrometry, PCR-RFLP, and sequencing of the ITS1-5,8S-ITS2 rDNA region.

Distribution of Insecticide Resistance Genetic Markers in the West Nile Virus Vector from South-Eastern Romania.

and mosquitoes are the vectors of West Nile virus in south-eastern Romania, an area of intense circulation and human transmission of this virus. The level of insecticide resistance for the mosquito populations in the region has not been previously assessed. mosquitoes collected between 2018 and 2019 in south-eastern Romania from different habitats were subjected to biotype identification by real-time PCR.

Nutrient and organic pollutants removal in synthetic wastewater by Pseudomonas aeruginosa and Chryseobacterium sp./biofilter systems.

Nutrient and organic pollution raise serious problems for aquatic ecosystems through the accumulation of organic carbon, the reduction of light penetration, and the loss of submerged aquatic vegetation. The over-enrichment of water with nitrogen and phosphorus leads to an imbalance in nutrient ratios, creating favorable conditions for toxic algal blooms, formation of oxygen-depleted water, etc. Thus, developing new technological solutions to reduce their amount is imperative.

Demonstration of Extract Inhibitory Effect on Biodeteriogenic Microbial Strain Growth, Biofilm Development, and Enzymatic and Organic Acid Production.

To the best of our knowledge, this is the first study demonstrating the efficiency of hydro-alcoholic extract (ASE) againstFigure growth, biofilm development, and soluble factor production of more than 200 biodeteriogenic microbial strains isolated from cultural heritage objects and buildings. The plant extract composition and antioxidant activities were determined spectrophotometrically and by HPLC-MS. The bioevaluation consisted of the qualitative (adapted diffusion method) and the quantitative evaluation of the inhibitory effect on planktonic growth (microdilution method), biofilm formation (violet crystal microtiter method), and production of microbial enzymes and organic acids.

[Aspects of yeast biodiversity].

Yeast biodiversity represents a dynamic scientific domain characterized by permanent emerging theories and accumulation of new data. Identification of genome structure for a number of yeast species and elucidation of regulatory pathways for species-specific metabolic networks, lead to development of numerous applications of yeasts in industry, biotechnology, therapeutics and bioremediation. The studies of the scientific community were long time focused on Saccharomyces cerevisae due mainly to its use in food production.

Roles of Hop1 and Mek1 in meiotic chromosome pairing and recombination partner choice in Schizosaccharomyces pombe.

Synaptonemal complex (SC) proteins Hop1 and Mek1 have been proposed to promote homologous recombination in meiosis of Saccharomyces cerevisiae by establishment of a barrier against sister chromatid recombination. Therefore, it is interesting to know whether the homologous proteins play a similar role in Schizosaccharomyces pombe. Unequal sister chromatid recombination (USCR) was found to be increased in hop1 and mek1 single and double deletion mutants in assays for intrachromosomal recombination (ICR).

[Biotherapeutic use of yeasts--importance of probiotic products].

Besides their important biotechnological and industrial applications, yeasts have been used during the last years, in obtaining probiotic products, along with lactic acid bacteria and various enzymes. Our study deals with some aspects regarding the use of yeasts as animal and human probiotics, and their possible mechanisms of action. Also, we present information on probiotic products synthesized by international and national companies.

Preliminary identification and classification of five new yeast strains isolated from oil-polluted environment.

Bioremediation is a very interesting alternative for restoring the oil-polluted ecosystems. Many studies concerning the possibility of using microorganisms (bacteria and yeasts) in the degradation of oil compounds have as starting point the isolation and taxonomical identification of new species and strains with degradative abilities. Our study focusses on the preliminary classification of five yeast strains (D1, D2, D3, D4 and D6) isolated from oil-polluted environments.

[Molecular taxonomy techniques used for yeast identification].

Due to the major impact of yeasts in human life based on the existence of pathogen yeast species and of species with biotechnological abilities, in the last few years new molecular techniques are performed for an accurate identification of natural isolates. Our study is aimed to review some of these techniques such as electrokariotyping by PFGE (Pulsed Field Gel Electrophoresis), estimation of the molar percentage of guanine and cytosine, the applications of PCR reaction in yeast identification using RAPD (Random amplified polymorphic DNA), UP-PCR (Universally Primed Polymerase Chain Reaction), MLST (Multilocus sequence typing) techniques, mtDNA and rDNA homology studies. Such molecular techniques complete the phenotypical characterization based on classical taxonomical tests allowing thus the polyphasic identification of the microorganisms.

Novel genes required for meiotic chromosome segregation are identified by a high-throughput knockout screen in fission yeast.

Two rounds of chromosome segregation after only a single round of DNA replication enable the production of haploid gametes from diploid precursors during meiosis. To identify genes involved in meiotic chromosome segregation, we developed an efficient strategy to knock out genes in the fission yeast on a large scale. We used this technique to delete 180 functionally uncharacterized genes whose expression is upregulated during meiosis.