7 August 2017
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All posts by Postępy Mikrobiologii
Adaptive evolution of yeasts genomes from Saccharomyces cerevisiae sensu stricto
28 July 2017
1. Wstęp. 2. Historia badań. 3. Występowanie winorośli i drożdży 4. Różnicowanie drożdży Saccharomyces cerevisiae 5. Wyodrębnianie gatunków w grupie Saccharomyces sensu stricto. 6. Budowa hybrydowa. 6.1. Drożdże piwowarskie lager. 6.2. Drożdże piwowarskie ale. 6.3. Drożdże winiarskie. 6.4. Drożdże do produkcji cydru. 7. Zmiany w budowie genomu. 7.1. Duże rearanżacje chromosomalne. 7.2. Zmienna liczby kopii genów. 7.3. Polimorfizm sekwencji. 7.4. Transfer DNA. Introgresje. 7.5. Sekwencje powtórzone. 8. Pangenom drożdży Saccharomyces sensu stricto. Różnorodność szczepów w obrębie grupy. 9. Modele ewolucji u drożdży Saccharomyces cerevisiae
Abstract: Saccharomyces sensu stricto yeasts includes important strains for many biotechnological procesess, specially in wine and brewery fermentation. Their plasticity and adaptation to different industrial niches may be result of complex genomic construction, polyploidy, chromosomal rearragements, DNA transfer, SNP occurrence. “Mixed” genetic lines known as hybrids, have more adaptation “abilities” than “pure” lines. Genomic datas from the first strain yeast S288c, sequencing in 1996, and from many others sequencing strains from different origins and applications was obtained. Adaptative evolution of industrial yeast using different molecular tools became as important area to research in last few years.
1. Introduction. 2. History of investigation. 3. Biogeography of grape and yeasts. 4. Differentiation of Saccharomyces cerevisiae yeasts. 5. Identification of yeasts in Saccharomyces cerevisiae group. 6. Hybrids. 6.1. Lager brewers yeasts. 6.2. Ale brewers yeasts. 6.3. Wine yeasts. 6.4. Cidr yeasts. 7. Changes in genome construction. 7.1. Gross chromosomal rearagements. 7.2. Variable number of gene copies 7.3. Sequence polymorphism. 7.4. DNA transfer. Introgressions. 7.5. Repeated sequences. 8. Pangenom of Saccharomyces sensu stricto yeasts. Biodiversity of strains in this group. 9. Evolution models in Saccharomyces cerevisiae yeasts
Differentiation of staphylococcal cassette chromosome mec (SCCmec) in methicillin-resistant coagulase-negative staphylococci
28 July 2017
1. Wstęp. 2. Budowa kaset SCCmec. 3. Występowanie kaset SCCmec u gronkowców koagulazo-ujemnych. 3.1. Zróżnicowanie kaset SCCmec u Staphylococcus epidermidis. 3.2. Identyfikacja kaset występujących u szczepów Staphylococcus haemolyticus. 3.3. Charakterystyka kaset u Staphylococcus hominis. 3.4. Występowanie kaset SCCmec u gronkowców sporadycznie izolowanych od chorych ludzi. 3.5. Charakterystyka kaset SCCmec obecnych u szczepów izolowanych od zwierząt. 4. Podsumowanie
Abstract: Staphylococcal chromosomal cassette mec (SCCmec) is a mobile genetic element that harbors the mec genes which encode resistance to methicillin and almost all β-lactam antibiotics. Also resistance genes for aminoglycosides, macrolides, tetracyclines can accrue on SCCmec elements. Coagulase-negative staphylococci are thought to be a reservoir of diverse SCCmec elements that can spread to Staphylococcus aureus or other species of Staphylococcus. A diversity of SCCmec types, with many new combinations of the mec and ccr gene complex as well as nontypeable types were recognized among the MR-CNS strains.
1. Introduction. 2. The structure of SCCmec elements. 3. Distribution of SCCmec types in coagulase-negative staphylococci. 3.1. Differentiation of SCCmec types in Staphylococcus epidermidis. 3.2. Identification of SCCmec in Staphylococcus haemolyticus. 3.3. Characteristics of SCCmec in Staphylococcus hominis. 3.4 Distribution of SCCmec types in sporadic staphylococcal isolates from patients. 3.5 Characteristics of SCCmec types in bacterial strains isolated from animal sources. 4. Summary
Pathogenesis and treatment of fungal infections by Candida spp.
28 July 2017
1. Wprowadzenie. 2. Epidemiologia kandydoz. 3. Czynniki zjadliwości Candida albicans. 3.1. Adhezja. 3.2. Proteazy aspartylowe. 3.3. Pleomorfizm. 4. Leczenie zakażeń o etiologii Candida spp. 5. Nowe trendy w poszukiwaniu antymikotyków. 6. Podsumowanie
Abstract: Candida albicans normally exists as harmless commensal inhabiting mucosal surfaces of healthy individuals. Yet, this opportunistic pathogen in immunocompromised hosts causes superficial or invasive life treating infections with high mortality rate. The incidence of candidiasis appeared to have several predisposing factors such as immunosuppressant or steroids treatments, long-term catheterization, invasive medical procedures, treatment with broad-spectrum antibiotic, destruction of skin by deep skin burns, local disorders of the gastrointestinal tract, diabetes mellitus, premature very low birth weight infants, immunologically compromised individuals, spread of HIV infection. This serious problem causes a need for better understanding of C. albicans virulence and antifungal treatment. This review features characterization of chosen virulence factors i.e.: adhesion, pleomorphism and enzymatic activity. Currently natural antifungal substances as well as synthetic derivatives are used at broad scale in candidiasis treatment. Recently, an increase of resistance to antifungal agents commonly used in fungal infection management has been observed. This world-scale problem generated a need for a search for novel antifungals.
1. Introduction. 2. Epidemiology of candidiasis. 3. Virulence factors of Candida albicans. 3.1. Adhesion. 3.2. Secreted aspartyl proteases. 3.3. Pleomorphism. 4. Candidiasis management. 5. New trends in the search for novel antifungal agents. 6. Summary
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