All posts by Postępy Mikrobiologii

Krezole a drobnoustroje środowiska glebowego

Cresols and the microorganisms of the soil environment
M. Zaborowska
23 June 2017

1. Wstęp. 2. Naturalne i antropogeniczne źródła krezoli w środowisku. 3. Toksyczność krezoli. 4. Drobnoustroje uczestniczące w rozkładzie krezoli. 5. Tlenowy katabolizm krezoli. 6. Beztlenowy katabolizm krezoli. 7. Mikrobiologiczna degradacja krezoli w środowisku glebowym. 8. Podsumowanie

Abstract: Phenolic compounds, including cresols, in the soil environment are a result of natural processes such as: biodegradation of lignins and tannins, and anthropogenic activity. Cresols are present in disinfectants as well as in the wastewater from chemical, petrochemical, pharmaceutical, paper and textile industry. They are also used in the production of insecticides, herbicides, medicines and antioxidants and have been classified as hazardous substances. Exposure of microorganisms to cresols can bring about changes in the structure of their cell membranes, resulting in their growth inhibition and cell lysis. However, there is still an untapped bioremediation potential in microorganisms, which are able to participate in the catabolism of cresols, both under aerobic and anaerobic conditions. The typical strategies of the aerobic degradation of cresols include the use of monooxygenase and dioxygenase enzymes. Thanks to these enzymes, atoms of molecular oxygen initiate fission of the aromatic ring structure. Under anaerobic conditions, the mechanisms of cresol decomposition  currently focus on the addition of fumarate, hydroxylation or carboxylation. The effectiveness of microorganisms in the degradation of cresols is not only due to their occurrence in consortia. They are also effective as single strains. The only controversial aspect involves using genetically modified organisms (GMOs) or their genes in the bioaugmentation process. This is because they are strictly selected and target only specific substrates. Due to this, they do not compete with autochthonous microorganisms undergoing natural selection.

1. Introduction. 2. Natural and anthropogenic sources of cresols in the environment. 3. Toxicity of cresols. 4. The microorganisms participating in the distribution of cresols. 5. Aerobic catabolism of cresols. 6. Anaerobic catabolism of cresols. 7. Microbial degradation of cresols in the soil environment. 8. Summary

Autor: Postępy Mikrobiologii
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Probiotyki i ich potencjalne właściwości antyoksydacyjne

Probiotics and their potential antioxidative activity
N. Trojan, P. Satora
23 June 2017

1. Wprowadzenie. 2. Antyoksydanty pochodzące z żywności. 3. Probiotyki. 4. Metody analizy właściwości antyoksydacyjnych. 5. Potencjał antyoksydacyjny probiotyków. 5.1. Produkty spożywcze zawierające probiotyki. 6. Doświadczenia in vivo – modele zwierzęce. 7. Badania kliniczne. 8. Mechanizm działania probiotyków jako antyoksydantów. 9. Podsumowanie

Abstract: Human population in the  XXI century is struggling with the increasing incidence of such diseases as obesity, diabetes, cancers, food allergies and many others. Recent studies have shown that oxidative stress caused by reactive oxygen species and free radicals, may underlie the occurrence of many diseases. Probiotics are known for their beneficial effects on health and are established as dietary adjuncts. Researchers are trying to find potential probiotic strains which can exhibit antioxidant properties along other health benefits. In vitro and in vivo studies have indicated that probiotics exhibit antioxidant potential. Also, many studies have shown that consumption of probiotics as dietary supplements, may reduce oxidative damage and modify activity of crucial antioxidative enzymes in human cells. Incorporation of probiotics in foods can provide a good strategy to supply dietary antioxidants, but more studies are needed to standardize the methods and evaluate antioxidant properties of probiotics before they can be recommended for their antioxidant potential. This paper presents the latest news related to probiotics and their antioxidative potential.

1. Introduction. 2. Antioxidants from food. 3. Probiotics. 4. Methods for antioxidative activity testing. 5. Probiotics antioxidative potential. 5.1. Food products containing probiotics. 6. In vivo studies – animal models. 7. Clinical trials. 8. Probiotics as antioxidants. 9. Conclusions

 

Autor: Postępy Mikrobiologii
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Różnorodność gatunkowa bakterii związanych z grzybami z rodzaju Tuber (trufla)

Species diversity of bacteria associated with fungi of the genus Tuber (truffles)
M. Siebyła, D. Hilszczańska
30 June 2017

1. Charakterystyka trufli. 2. Różnorodność gatunkowa bakterii. 3. Podsumowanie

Abstract: Truffles (Tuber spp.) are ascomycete hypogeous fungi, which form ectomycorrhizae with roots of trees, shrubs and herbaceous plants. Their fruiting bodies are valued for their distinctive aroma. The aroma might be partially due to complex bacterial community which colonizes their fruiting bodies. Some bacterial species are also believed to promote the truffle’ fruitification due to the fixation of nitrogen inside the developing truffles. Although truffles, especially of the species Tuber aestivum, are getting more popular and are widely cultivated, little is still known about their biology, composition and the role of their associative microbes. The aim of this study was to present the current knowledge about the bacterial communities associated with black truffles and their potential influence on the truffle life cycle and maturation.

1. Characteristics of truffles. 2. Diversity of bacterial species. 3. Conclusion

Autor: Postępy Mikrobiologii
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Mikrobiom człowieka

The human microbiome
M. Malinowska, B. Tokarz-Deptuła, W. Deptuła
30 June 2017

1. Wprowadzenie 2. Mikrobiom skóry 3. Mikrobiom jamy ustnej 4. Mikrobiom przewodu pokarmowego 5. Mikrobiom dróg oddechowych 6. Mikrobiom układu moczowo-płciowego 7. Podsumowanie

Abstract: The human microbiome is represented by bacteria, archea, viruses, including bacteriophages, and fungi. These microorganisms colonize the human body and are necessary for the maintenance of homeostasis, including human immune status. Even though human microbiome is vital for the functioning of the human organism, it is still poorly understood, especially when it comes to archea, but also viruses and fungi. The aim of this study is to present the current state of knowlegde about the microorganisms inhabiting essential biotypes of the human body, i.e. the skin, the mouth and the digestive tract, as well as the respiratory and urogenital tract.

1. Introduction. 2. The skin microbiome. 3. The oral microbiome. 4. The digestive tract microbiome. 5. The respiratory tract microbiome. 6. The urinary tract microbiome. 7. Summary

Autor: Postępy Mikrobiologii
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Zastosowanie bakteryjnych pęcherzyków zewnątrzbłonowych w konstrukcji szczepionek

Application of the bacterial outer membrane vesicles in vaccine design
J. Klim, R. Godlewska
30 June 2017

1. Wprowadzenie. 2. Biogeneza pęcherzyków zewnątrzbłonowych. 3. Funkcje pęcherzyków zewnątrzkomórkowych. 3.1. Udział w odpowiedzi na czynniki stresogenne. 3.2. Udział w transporcie pozakomórkowym. 3.3. Udział w tworzeniu biofilmu. 4. Pęcherzyki zewnątrzbłonowe w konstrukcji szczepionek. 4.1. Neisseria meningitidis. 4.2. Vibrio cholerae. 4.3. Bordetella pertussis. 4.4. Chlamydia trachomatis. 4.5. Burkholderia pseudomallei. 4.6. Acinetobacter baumannii. 4.7. Francisella noatunensis. 4.8. Shigella spp. 4.9. Campylobacter jejuni. 5. Podsumowanie

Abstract: Outer membrane vesicles (OMVs) are extracellular structures produced by most gram‑negative bacteria, including pathogens of humans and animals. OMVs play an important role in the physiology of microorganisms and are an integral part of many biological processes. Following the discovery that they are able to transport many biomolecules, also these which have the ability to interact with the immune system, their potential use as non‑replicating vaccines has become an important aspect of immunotherapeutic researches. These nano-sized elements exhibit remarkable potential for immunomodulation of immune response, thanks to the ability to deliver naturally or artificially incorporated antigens within their structure. First vaccine based on outer membrane vesicles was developed almost 30 years ago against Neisseria meningitidis serogroup B. This review presents some basic information on biogenesis and functions of OMVs. It also provides examples of pathogens, whose OMVs (in natural or modified form) have been used in the development of immunogenic vaccines against the organisms from which the vesicles had been obtained. OMVs are proving to be more versatile than first conceived and may become important part of biotechnology research, not limited to medical applications.

1. Introduction. 2. Outer membrane vesicles biogenesis. 3. Biological functions of outer membrane vesicles. 3.1. Role in response to stressors. 3.2. Role in the extracellular transport. 3.3. Role in biofilm formation. 4. OMVs in vaccine construction. 4.1. Neisseria meningitidis. 4.2. Vibrio cholerae. 4.3. Bordetella pertussis. 4.4. Chlamydia trachomatis. 4.5. Burkholderia pseudomallei. 4.6. Acinetobacter baumannii. 4.7. Francisella noatunensis. 4.8. Shigella spp. 4.9. Campylobacter jejuni. 5. Conclusions

Autor: Postępy Mikrobiologii
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Current Issue

Current Issue

Advancements of Microbiology
Volume 63 (2024): Issue 3

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PTM

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