All posts by Postępy Mikrobiologii

Chorobotwórczość Lactobacillus sp. – czynniki ryzyka, identyfikacja, antybiotykooporność

Pathogenicity of Lactobacillus sp. – risk factors, identification, antibiotic resistance
M. Kłos
1 July 2017

1. Wstęp. 2. Czynniki zwiększające ryzyko infekcji Lactobacillus sp. 3. Identyfikacja Lactobacillus sp. 4. Chorobotwórczość Lactobacillus sp. 5. Podsumowanie

Abstract: Lactobacilli are found in the mucous membrane of the mouth, in the gastrointestinal tract (GIT) and in the genitourinary tract. It is known that lactobacilli have a beneficial effect on our health and are used in the production of fermented milk, yoghurts, cheese, and probiotics. However, in this article I show that lactic acid bacteria also cause many diseases. Lactobacilli produce lactic acid which acidifies the environment. There are some factors increasing the risk of infection caused by lactobacilli, such as neutropenia in immunocompromised patients and certain underlying diseases, especially diabetes. Also, lactobacilli have a natural resistance to some antibiotics, especially vancomycin. The identification of lactobacilli can be very difficult due to the number of species, subspecies and genotypic or phenotypic traits. The most advanced procedures are molecular DNA-based techniques. Conventional biochemical tests can be also used to determine some differences. Lactobacilli infection can affect both a single organ and the whole organism, causing for example lactobacillemia. The main disease caused by lactobacilli is endocarditis.

1. Introduction. 2. Risk factors. 3. Identification. 4. Pathogenicity. 5. Conclusions

Autor: Postępy Mikrobiologii
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Francisella tularensis – podstępny patogen

Francisella tularensis – a deceitful pathogen
K. Formińska, A.A. Zasada
1 July 2017

1. Wstęp. 2. Chorobotwórczość, źródła i drogi zakażenia. 3. Występowanie choroby. 4. Wewnątrzkomórkowy cykl życiowy F. tularensis. 5. Czynniki zjadliwości F. tularensis. 5.1. Otoczka. 5.2. Lipopolisacharyd (LPS). 5.3. Pili typu IV. 5.4. Regulator MglA. 5.5. Francisella Pathogenity Island (FPI). 5.6. Białka błony zewnętrznej. 5.7. Białka wydzielnicze i systemy sekrecji. 6. Podsumowanie

Abstract: Francisella tularensis is an intracellular bacterial pathogen which causes a potentially lethal disease named tularemia. Some studies have been conducted to describe and identify the virulence factors of F. tularensis. This pathogen is able to infect a variety of cells of various hosts, including wild animals, especially rabbits, hares and rodents, and humans. This may suggest that genes of F. tularensis must adapt to many different intraorganismal environments. Still, little is known about the virulence of F. tularensis. This review focuses on the main virulence factors of F. tularensis which are involved in intramacrophage replication and its survival mechanisms during infection.

1. Introduction. 2. Pathogenicity and source of infection. 3. Epidemiology. 4. Intracellular life cycle. 5. Virulence factors. 5.1. Capsule. 5.2. LPS. 5.3. Type IV Pili (Tfp). 5.4. Regulator MglA. 5.5. Francisella Pathogenity Island (FPI). 5.6. Outer membrane proteins (OMP). 5.7. Secreted proteins and secretion systems. 6. Summary

Autor: Postępy Mikrobiologii
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Czynniki warunkujące zdolności adhezyjne bakterii z rodzaju Lactobacillus

Factors determing the adhesive capacity of Lactobacillus bacteria
A. Paliwoda, A. Nowak
1 July 2017

1. Wstęp. 2. Etapy adhezji bakterii Lactobacillus do nabłonka jelitowego. 3. Czynniki uczestniczące w adhezji. 3.1. Czynniki białkowe. 3.2. Czynniki niebiałkowe. 3.3 Czynniki środowiskowe. 3.4. Tworzenie agregatów oraz oddziaływania hydrofobowe. 4. Podsumowanie

Abstract: The ability of Lactobacillus to adhere to the intestinal epithelium is one of the most important criterion in the selection of probiotic strains. Adherence allows microorganisms to survive and temporarily colonize the digestive system, which is necessary to induce beneficial effects on the host. Adhesion is a very complex, multistep process and, although there are many proposed theories, the exact mechanism is still not fully understood. A crucial role in the formation of the adhesive interactions plays the bacterial cell wall and its components, such as exopolisaccharydes, lipoteichoic acids and various proteins e.g. S-layer proteins.

1. Introduction. 2. Stages of Lactobacillus adhesion to intestinal epithelium 3. Adhesion factors. 3.1. Protein factors 3.2. Non-protein factors. 3.3. Environmental factors. 3.4. Aggregation and hydrophobic interactions. 4. Summary

Autor: Postępy Mikrobiologii
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Niepandemiczne koronawirusy człowieka – charakterystyka i diagnostyka

Non-pandemic human coronaviruses – characteristics and diagnostics
E. Abramczuk, K. Pancer, W. Gut, B. Litwińska
1 July 2017

1. Historia. 2. Taksonomia i występowanie. 3. Struktura i namnażanie się koronawirusów. 4. Receptory komórkowe wykorzystywane przez koronawirusy człowieka. 5. Zakażenie człowieka – transmisja, objawy, charakterystyka. 6. Diagnostyka. 7. Podsumowanie

Abstract: In this article, the characteristics of human coronaviruses (HCoV) are presented. Currently, six human coronaviruses are known: HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1, HCoV-SARS and HCoV-MERS. The first human coronaviruses were described in the sixties of the twentieth century, the last one, HCoV-MERS, in 2012 y. Coronaviruses can cause mild, asymptomatic infections as well as severe respiratory diseases, like pneumonia and bronchiolitis. The symptoms of HCoV infection are mainly: fever, nasopharyngitis, cough, bronchiolitis, pneumonia. Infections due to HCoV occur during the whole human life, but aremost frequent in children. They can occur throughout the year, but are most common in the winter season. Treatment of HCoV infections is usually symptomatic. Diagnosis of HCoV is mainly based on molecular technics such as quantitative PCR. Serological tests are only used for epidemiological purposes.

1. History. 2. Taxonomy and occurrence. 3. The structure and amplification of human coronaviruses. 4. Cell receptors used by human coronaviruses. 5. Human infection – transmission, symptoms, characteristics. 6. Diagnostics. 7. Summary

Autor: Postępy Mikrobiologii
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Plazmidy jako wektory do terapii genowej

Plasmids – vectors for gene therapy
P. Zaleski, P. Wawrzyniak, A. Sobolewska, G. Płucienniczak
1 July 2017

1. Wstęp. 2. Naturalna modyfikacja DNA jako przeszkoda w stosowaniu plazmidów w terapii genowej. 3. Bezpieczeństwo użycia plazmidowego DNA. 4. Wprowadzenie pDNA do komórek eukariotycznych. 5. Los plazmidowego DNA po wprowadzeniu do komórek eukariotycznych. 6. Terapie genowe bazujące na pDNA. 7. Inne kierunki rozwoju terapii genowych opartych na plazmidowym DNA. 7.1 Baktofekcja. 7.2. Alternatywna terapia genowa (Alternative Gene Therapy – AGT). 7.3. Hydrożele. 7.4. Minikoliste DNA. 7.5. Mininici DNA. 8. Podsumowanie

Abstract: The first confirmed transfer of genetic material in human was performed in 1990. Ever since, gene therapy was considered to be one of the best promising treatments of genetic diseases. The sine qua non of successful gene therapy are efficient genetic vectors. Recently, the most frequently used vectors in clinical trials for genetic therapies are virus-based and plasmid-based. A range of features makes plasmids useful for gene therapy, however, they have also some characteristics which make it difficult to consider plasmids as ideal vectors. The main goal of this article is to address and describe these unfavourable factors.

1. Introduction. 2. Natural modification of DNA as an obstacle to the use of plasmids for gene therapy. 3. Plasmid DNA usage safety. 4. Plasmid DNA entry into eucaryotic cells. 5. Post-entry fate of plasmid DNA in eucaryotic cells. 6. pDNA-based gene therapies. 7. Alternative routes of development of pDNA-based gene therapies. 7.1. Baktofection. 7.2. Alternative Gene Therapy – AGT. 7.3. Hydrogels. 7.4. DNA minicircles. 7.5. DNA ministrings. 8. Summary

Autor: Postępy Mikrobiologii
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Advancements of Microbiology
Volume 63 (2024): Issue 3

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PTM

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