All posts by Postępy Mikrobiologii

Filowirusy – wirusy obecne od milionów lat – dlaczego teraz wybuchła tak wielka epidemia?

Filoviruses – viruses existing for millions of years – why do we have such a big outbreak now?
K. Pancer, W. Gut, B. Litwińska

1. Rys historyczny i charakterystyka. 2. Struktura i zmienność EBOV. 3. Rezerwuar zwierzęcy filowirusów. 4. Podstawowe etapy cyklu życiowego wirusa Ebola w komórce. 5. Wybrane mechanizmy patogenności wirusa Ebola. 6. Paleowirusologia. 7. Podsumowanie

Abstract: Ebola virus, discovered in 1976, caused the largest epidemic among humans in 2014. In this paper, we have discussed the systematic position of Ebolavirus, the ecology of these viruses, the essential elements of pathogenesis of infections as well as comparative characteristics of Filoviruses infectious biology. According to the paleovirological data, these features were developed during millions of years of the co-evolution process and co-existence of pathogens and hosts. It is likely that changes of Ebola virus biology are not the reason for such substantial changes in the epidemiology of Ebola virus infections. Analysis of factors associated with the characteristics of the present epidemic (size, region) indicate that the main reason for such big epidemic may be the changes related to both humans activity, mainly transformation of the environment, and the ability of bats (natural hosts of Filoviruses) to adapt to the new ecological conditions. These processes may cause more outbreaks in the future, also on a large scale, and require taking appropriate actions to reduce the risks.

1. History and characteristics of filoviruses. 2. The structure and variability of EBOV. 3. Animal reservoir of Filoviruses. 4. Basics of the Ebola virus life cycle in the cell. 5. Selected mechanisms of pathogenicity of Ebola virus. 6. Filovirus paleovirology. 7. Summary

Koncepcja chromidu i jej znaczenie dla klasyfikacji pozachromosomowych replikonów bakterii

The concept of chromid and its influence on the classification of bacterial extrachromosomal replicons
J. Czarnecki, D. Bartosik

1. Wprowadzenie. 2. Nazewnictwo replikonów niezbędnych. 3. Koncepcja chromidu. 4. Identyfikacja i klasyfikacja chromidów. 5. Chromidy w genomach bakterii. 6. Ewolucyjne korzyści wynikające z obecności chromidów. 7. Podsumowanie

Abstract: Extrachromosomal replicons are common components of bacterial genomes. While the genetic information essential for growth and division of bacterial cells is located within the chromosome, the extrachromosomal replicons, usually classified as plasmids, can provide functions which are critical for the survival of a bacterium in a specific environment; however, they are not indispensable for the viability of the host cells. Comparative genomic studies revealed that in many bacterial genomes some chromosomal genes had been transferred into the co-occurring plasmids. This phenomenon has led to the generation of essential extrachromosomal replicons, called chromids, sharing features of both chromosomes and plasmids. The prevalence of chromids in bacteria and their conserved character within certain taxonomic groups suggest an important role for these replicons in the evolution of bacteria.

1. Introduction. 2. Nomenclature of essential replicons. 3. The concept of chromid. 4. Identification and classification of chromids. 5. Chromids in bacterial genomes. 6. Evolutionary significance of chromids. 7. Summary

Mikrobiosensory beleczkowe w mikrobiologii

Application of cantilever-based microbiosensors in microbiology
A. Wańczyk, B. Łabędź, Z. Rajfur

1. Wstęp. 2. Przystosowanie układu do precyzyjnych pomiarów biologiczno-chemicznych. 3. Zastosowanie mikrobiosensorów beleczkowych w pomiarach  biologicznych. 3.1. Mikrobiologia. 3.1.1. Wykrywanie mikroorganizmów. 3.1.2. Określanie masy mikroorganizmów. 3.1.3.Badanie wzrostu mikroorganizmów. 3.2. Proteomika. 3.3. Inne zastosowania mikrobiosensorów beleczkowych. 4. Podsumowanie

Abstract: This paper presents applications of cantilever-based microbiosensors in microbiology and other biological fields. These devices can be employed in a wide range of experiments due to their high sensitivity and capability of performing label-free and real-time measurements. Cantilever-based microbiosensors are employed in a variety of measurements, such as single cell mass, concentration of specific substances, their density and viscosity, fluid flow velocity, heat of reaction or detection of trace amounts of specified substances. All these applications ares possible, because cantilever surface can be specifically functionalized. In the last few years, the cantilever-based microbiosensors have been significantly improved to obtain even higher precision of measurement which allows for their new, unique applications with live biological systems.

1. Introduction. 2. Adaptation of the system for precise bio-chemical measurements. 3. Application of cantilever-based microbiosensors in biological  measurements. 3.1. Microbiology. 3.1.1. Detection of microorganisms. 3.1.2. Microorganism mass determination. 3.1.3. Microorganism growth studies. 3.2. Proteomics. 3.3. Other applications of cantilever-based microbiosensors. 4. Summary

Drożdże w bioindykacji zanieczyszczeń rolniczych

Yeast as bioindicators of agricultural pollution
U. Wachowska, A. D. Stasiulewicz-Paluch

1. Wstęp. 2. Drożdże. 3. Przydatność drożdży do oceny zanieczyszczeń środowiska. 3.1. Środki ochrony roślin w środowisku. 3.2. Biotesty w oparciu o hamowanie wzrostu. 3.3. Testy genotoksyczności. 3.4. Testy endokrynne. 4. Drożdże w toksykogenomice. 4.1. Zalety drożdży wykorzystywanych w toksykogenomice. 4.2. Narzędzia transkrypto-, proteo- i matabolomiczne stosowane w toksykogenomice drożdży. 4.3. Toksykogenomika funkcjonalna genów drożdży. 4.4.  Toksykogenomika drożdży w ocenie zanieczyszczenia środowiska rolniczego. 5. Podsumowanie

Abstract: This review paper discusses a new set of biotests used for toxicity assessment of plant protection products and their residues in agricultural ecosystems. Recent regulations have imposed restrictions on the use of animals for scientific purposes, and also the obligation to analyze auxiliary substances in plant protection products and to identify endocrine disrupters. The major characteristics of yeasts and their taxonomic classification are describedin the study. Commercial yeast-based biotests and potential uses of yeasts in environmental studies and toxicogenomics are also analyzed.

1. Introduction. 2. Yeast. 3. Yeast as indicators of environmental pollution. 3.1. Plant protection products in the environment. 3.2. Growth inhibition biotests. 3.3. Genotoxicity tests. 3.4. Endocrine tests. 4. Yeasts in toxicogenomics. 4.1. The advantages of using yeasts in toxicogenomics. 4.2. Transcriptomics, proteomics and metabolomics tools in yeast toxicogenomics. 4.3. Yeast functional toxicogenomics. 4.4. Yeast toxicogenomics in agricultural pollution assessment. 5. Conclusions

Udział czynników wirulencji Enterococcus faecalis w rozwoju chorób miazgi i tkanek okołowierzchołkowych

Virulence factors of Enterococcus faecalis in relation to pulp diseases and periapical infections
E. Prażmo, R. Godlewska, M. Kwaśny, A. Mielczarek

1. Wstęp. 2. Znaczenie E. faecalis w zakażeniach endodontycznych zębów. 3. Czynniki wirulencji E. faecalis. 4. Mechanizmy zjadliwości E. faecalis. 5. Podsumowanie

Abstract: Enterococci are Gram-positive, catalase-negative, facultative anaerobic bacteria. They inhabit the oral cavity and gastrointestinal tract in humans as normal commensals. However, they can also cause infections of the urinary tract, surgical wound infections, neonatal sepsis and endocarditis. Enterococcus faecalis is associated with great number of refractory endodontic infections. The prevalence of these bacteria ranges from 24 to 77% in teeth with failed endodontic treatment and E. faecalis very often coexists with chronic apical periodontitis. Understanding the virulence, ecology and epidemiology of E. faecalis is essential for limiting all kinds of diseases caused by this pathogen. This article focuses on the bacterial mechanisms related to endodontic infections and periradicular inflammatory response. The most explored virulence factors are: the aggregation substance, surface adhesins, lytic enzymes, lipoteicholic acid, sex pheromones. All of them are associated with specific stages of tissue invasion. E. faecalis has also developed elaborated mechanisms of antibiotic resistance, as well as the ability to organize in a biofilm and overcome low-nutrient conditions. These adaptations help in the modulation of host immune response and make E. faecalis very difficult to eradicate by available antibiotics and disinfectants. Recognition and understanding of the nature of this pathogen will help endodontic microbiology to completely eliminate endodontic infections for successful endodontic treatment.

1. Introduction. 2. Importance of E. faecalis in endodontic infections. 3. Virulence factors of E. faecalis. 4. Virulence mechanisms of E. faecalis. 5. Summary

Najnowszy numer

Najnowszy numer

2018, 57, 4

O Towarzystwie


Celem Polskiego Towarzystwa
Mikrobiologów jest propagowanie rozwoju nauk mikrobiologicznych

i popularyzowanie osiągnięć
mikrobiologii wśród członków Towarzystwa oraz szerokich kręgów społeczeństwa. Formami działalności jest organizowanie zjazdów, posiedzeń naukowych, kursów, wykładów
i odczytów oraz konkursów prac naukowych; wydawanie i popieranie wydawania czasopism naukowych, książek
i innych publikacji
z dziedziny mikrobiologii; opiniowanie o stanie i potrzebach mikrobiologii polskiej

i występowanie w jej sprawach wobec
władz państwowych; współpraca
z pokrewnymi stowarzyszeniami
w kraju i za granicą.