All posts by Postępy Mikrobiologii

Beztlenowe ziarenkowce Gram-dodatnie (GPAC) – diagnostyka i znaczenie kliniczne

Gram-positive anaerobic cocci (GPAC) – diagnostic and clinical significance
M. Kierzkowska, A. Majewska, A. Sawicka-Grzelak, G. Młynarczyk
10 August 2017

1. Wstęp. 2. Systematyka beztlenowych ziarenkowców Gram-dodatnich. 3. Znaczenie kliniczne GPAC. 4. Diagnostyka laboratoryjna. 4.1. Hodowla. 4.2. Identyfikacja fenotypowa. 4.3. Identyfikacja genotypowa. 5. Podsumowanie

Abstract: Among the Gram-positive anaerobic bacteria associated with clinical infections, the Gram-positive anaerobic cocci (GPAC) are the most predominant and account for approximately 25–30% of all isolated anaerobic bacteria from clinical specimens. They can be cultured from a wide variety of sites, particularly abscesses and infections of the mouth, skin and soft tissues, bone and joints and upper respiratory and female genital tracts. Most infections involving GPAC are polymicrobial. Still, routine culture and identification of these slowly growing anaerobes to the species level has been limited in the diagnostic laboratory, mainly due to the requirement of prolonged incubation times and time-consuming phenotypic identification. The development of molecular methods such as PCR, multiplex PCR, sequencing of the 16S rRNA gene have led to improved identification of GPAC. In recent years, MALDI-TOF MS has been implemented in routine laboratories and utilized as a completely new approach for the identification of bacteria. Data from molecular methods have led to extensive taxonomic changes during the last decades and also to the occurrence of new genera and species. This review describes clinical significance of GPAC and virulence factors one of the most pathogenic species – Finegoldia magna.

1. Introduction. 2. Taxonomy of Gram-positive anaerobic cocci. 3. Clinical significance of GPAC. 4. Laboratory diagnostic. 4.1. Culture. 4.2. Phenotypic identification. 4.3. Genotypic identification. 5. Summary

Autor: Postępy Mikrobiologii
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Ukierunkowana ewolucja enzymów pochodzenia mikrobiologicznego

Directed evolution of microbial enzymes
K. Hupert-Kocurek, A. Banaś, D. Wojcieszyńska, U. Guzik
10 August 2017

1. Wprowadzenie. 2. Udoskonalanie enzymów metodami nierekombinacyjnymi. 3. Udoskonalanie enzymów metodami rekombinacyjnymi. 4. Podsumowanie

Abstract: Enzymes of microbial origin are extensively used in different industrial processes. However, very often these biocatalysts do not meet the requirements for a large-scale application and its properties have to be optimized. This includes not only the chemoselectivity, regioselectivity and stereoselectivity, but also long-term stability of the biocatalyst at certain temperatures or pH-values and activity in the presence of high substrate concentrations. Protein engineering has emerged as an important tool to overcome the limitations of natural enzymes as biocatalysts. There are two general strategies for protein engineering, rational design and directed evolution. In rational design detailed knowledge of the structure and function of the protein is used to make desired changes. Directed evolution involves either a random mutagenesis of the gene encoding the enzyme (e.g. by error-prone PCR) or recombination of gene fragments derived from DNase degradation, random priming recombination, random chimeragenesis on transient templates or recombined extension on truncated templates. In this review the essential methods for directed evolution of enzymes are described and various examples for the application of these protein engineering tools are provided.

1. Introduction. 2. Improvement of enzymes using non-recombinant methods. 3. Improvement of enzymes using gene-recombination methods. 4. Summary

Autor: Postępy Mikrobiologii
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Rola i znaczenie proteinaz związanych z powierzchnią komórek bakterii Lactobacillus helveticus

The role and significance of cell – envelope associated proteinases of Lactobacillus helveticus bacteria
K. Skrzypczak, W. Gustaw, A. Waśko
10 August 2017

1. Wstęp. 2. Właściwości peptydaz związanych z powierzchnią komórek (CEP) bakterii Lactobacillus helveticus. 2.1. Budowa i charakterystyka białek CEP. 2.2. Mechanizm katalitycznego działania CEP’s. 2.3. Geny kodujące białka CEP oraz mechanizmy kontrolujące ich biosyntezę. 3. Mechanizm działania systemu proteolitycznego Lactobacillus helveticus. 4. Znaczenie i możliwości praktycznego wykorzystania systemu proteolitycznego bakterii Lactobacillus helveticus. 5. Podsumowanie

Abstract: The authors present the current state of knowledge about the proteolytic system of Lactobacillus helveticus and compare it with system presents in other lactic acid bacteria (LAB). The proteolytic activity of these bacteria is used in food production, where the degradation of the protein is responsile for flavor, aroma and texture. From all lactic acid bacteria L. helveticus have the highest proteolytic activity, which directly involved the cell envelope associated proteinases (CEPs). This also contribute to a formation of bioactive peptides referring to value of health promoting food. L. helveticus bacteria seem to be unique in terms of variation of the number of genes CEP proteins of all lactic acid bacteria. This paper review focuses on the genetic basis determining the properties of CEP proteins occurring in L. helveticus and possibilities of practical application of these bacterial strains.

1. Introduction. 2. Properties of Cell – Envelope associated Proteinases (CEPs) of Lactobacillus helveticus. 2.1. Structure and characterization of CEPs. 2.2. The mechanism of the catalytic activity of CEP’s 2.3. Genes encoding CEPs and their biosynthesis control mechanisms. 3. The mechanism of proteolytic system in Lactobacillus helveticus. 4. The importance and possibilities of practical use the proteolytic system of Lactobacillus helveticus. 5. Summary

Autor: Postępy Mikrobiologii
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Mikrobiologiczna degradacja niesteroidowych leków przeciwzapalnych

Microbial degradation non-steroidal anti-inflammatory drugs
U. Guzik, K. Hupert-Kocurek, D. Wojcieszyńska
10 August 2017

1. Wprowadzenie. 2. Charakterystyka niesteroidowych leków przeciwzapalnych. 3. Degradacja niesteroidowych leków przeciwzapalnych metodami fizyko-chemicznymi. 4. Szlaki biologicznej degradacji niesteroidowych leków przeciwzapalnych. 5. Podsumowanie

Abstract: In the recent years, commonly used non-steroidal anti-inflammatory drugs (NSAIDs) are widely detected in the environment. These biologically active substances and their continuous inflow into the environment may lead to their accumulation in the environment and chronic exposure of organisms. This in turn may cause the potential negative effects on living organisms. While the transformation mechanisms of non-steroidal anti-inflammatory drugs in the human body and in other animals have been extensively studied, degradation of these drugs by bacteria (including their degradation pathways and degradation products) has seldom been investigated and are largely unknown. Therefore, the objective of this paper is presentation actual stage of knowledge about microbiological degradation pathways of NSAIDs such as naproxen, ibuprofen, diclofenac, paracetamol.

1. Introduction, 2. Characterization of non-steroidal anti-inflammatory drugs, 3. Degradation of non-steroidal anti-inflammatory drugs by physicochemical methods, 4. Pathways of biological degradation of non-steroidal anti-inflammatory drugs, 5. Conclusion

Autor: Postępy Mikrobiologii
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Grzyby z rodzaju Neotyphodium – endofity traw

Grass endophytes of the Neotyphodium genus
B. Wiewióra
10 August 2017

1. Wprowadzenie. 2. Charakterystyka grzybów z rodzaju Neotyphodium. 3. Metody identyfikacji. 4. Alkaloidy wytwarzane przez endofity. 5. Choroby zwierząt wywoływane przez alkaloidy produkowane przez grzyby z rodzaju Neotyphodium. 6. Wpływ alkaloidów na odporność traw na stresy. 6.1. Stresy abiotyczne. 6.2. Stresy biotyczne. 7. Występowanie endofitów w Polsce i na świecie. 8. Podsumowanie

Abstract: Endophytes are fungi of the genus Neotyphodium, that live in symbiosis with grasses. The effects of this symbiosis can be both negative and positive. The negative effect may be due to alkaloids produced by endophytes, that in higher concentrations are toxic to animals. On the other hand, the effect of symbiosis can be beneficial to plants, because the grass becomes more resistant to biotic and abiotic stresses such as drought, pests or diseases. The most common alkaloid produce by Neotyphodium fungi are ergovaline and lolitrem B.
Current state of knowledge on the settlement of grasses by these fungi in Poland is rather small. These fungi are usually present in the seeds of Festuca ovina, F. pratensis, F. arundinacea and Lolium perenne. Endophytes were found in plants of permanent grasslands. The most often infected plants were from: Festuca pratensis, F. arundinacea, F. rubra, F. ovina and Lolium perenne. Traces of endophyte presence was also found in the ecotypes of Deschampsia caespitosa, F. capillata, F. gigantea, L. multiflorum, Poa pratensis and Phleum pratense. It was observed that fungi from the genus Neotyphodium occurring in the pasture sward can produce alkaloids, but its production is a variable trait, even within a single ecotype. The average ergovaline content in grass from the permanent pasture in some areas exceeded the threshold level above which disease symptoms in animals may occur.

1. Introduction. 2. Characterization of fungi from Neotyphodium genus. 3. Identification methods. 4. Alkaloids produced by endophytes. 5. Animal diseases caused by alkaloids produced by fungi of the genus Neotyphodium. 6. Effect of alkaloids on grass resistance to stress. 6.1. Abiotic stresses. 6.2. Biotic stresses. 7. The occurrence of endophytes in Poland and in the world. 8. Summary

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Advancements of Microbiology
Volume 63 (2024): Issue 3

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