rss_2.0Postępy Mikrobiologii - Advancements of Microbiology FeedSciendo RSS Feed for Postępy Mikrobiologii - Advancements of Microbiologyępy Mikrobiologii - Advancements of Microbiology Feed More than Just a Bacterial Hunter<abstract> <title style='display:none'>Abstract</title> <p><italic>Bdellovibrio bacteriovorus</italic> is a predatory gram-negative delta-proteobacteria that preys on other gram-negative bacterial species. With the surge in the cases of Anti-Microbial Resistance and the demand to replace conventional antibiotics, this predatory attribute of <italic>B. bacteriovorus</italic> has led to a vast number of studies in the last decade alone. These studies demonstrated various aspects of predation and proposed using <italic>B. bacteriovorus</italic> as an alternative new approach to conventional antibiotics in humans. Here we review the current progress made in this promising new area of research to develop novel antibacterial approaches.</p> </abstract>ARTICLEtrue Przewodu Pokarmowego Człowieka – Wybrane Dane<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>The paper presents new data indicating the composition of the human gastrointestinal microbiome, consisting of bacteria, archaea, viruses (including bacteriophages), as well as eukaryotic and heterotrophic organisms such as fungi – the existence of which in the gastrointestinal tract is referred to as the mycobiome. The human digestive tract, divided into the oral cavity, pharynx, esophagus, stomach, and small and large intestine, inhabited by the microorganisms mentioned above, forms a specific qualitative and quantitative, rich and diverse specific ecosystem. Thanks to the use of bioinformatic and molecular methods, including metagenomic sequencing, it is still being discovered. In this review, systematic groups of bacteria, archaea, viruses, and fungi occurring in individual sections of the gastrointestinal tract are presented, and enterotypes of the large intestine are indicated. Considering the amounts of the above-mentioned groups of microorganisms in individual sections of the gastrointestinal tract of the human, the environment of the large intestine and oral cavity are the richest parts of the microbiome, while the throat and esophagus are the poorest. Among the microbiome of the digestive tract of the human, the most numerous group are bacteria located in the mouth and small intestine, while the the most limited group of bacteria is registered in the pharynx and esophagus. Archaea, on the other hand, have been described most frequently in the large intestine and stomach, and were not found in the throat and small intestine. Most viruses in the gastrointestinal tract were found in the large intestine and the oral cavity, while they were absent in the stomach. The fungi found in the microbiome were most abundant in the large intestine and stomach, and the smallest amount in the throat and small intestine.</p> </trans-abstract>ARTICLEtrue Organic Acids as Leaching Agents for Metal Recovery Processes<abstract> <title style='display:none'>Abstract</title> <p>Minerals have been important throughout history, but nowadays, their use has increased, as well as their extraction needs. Therefore, due to the growing demand for metals, and both the depletion of high-grade ores and their related environmental concerns, the mining industry has been forced to leave behind the past traditional techniques of metal recovery (use of inorganic acids), and adopt eco-friendlier alternatives, such as the utilization of weaker leaching agents, such as organic acids. Thus, the present review is focused on the use of microbially-produced organic acids as a promising alternative to conventional techniques in the mining industry, with emphasis on the following topics: a) the advantages and disadvantages of the use of organic acids for leaching purposes, b) the main microorganisms studied for the production of these organic acids, c) a summary of the latest reports on bioleaching as well as a comparison of the existent techniques; d) the explanation of leaching mechanisms where organic acids may be involved, to fulfill metal recovery; and, e) interactions between metallic ions and organic acids. The review of the current knowledge regarding the use of organic acids for leaching purposes seeks the visualization of relevant strategies that may be improved for metal-recovery processes, intending to develop circular economy practices that may have the potential to be implemented at an industrial scale.</p> </abstract>ARTICLEtrue i Współczesne Metody Stabilizacji Wina<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Enology, a science dealing with issues related to wine production, combines ancient tradition with the present time. It was not until Louis Pasteur proved that vinification does not happen by itself and that microorganisms are responsible for this process. It was a beginning for a branch of enology focused on the microbiology of wine, which led to gradual evolution of production methods and the development of advanced techniques for wine stabilization. Nevertheless, alternative methods that can replace or modify the sulfation process as wine preservation are still sought. Physical and chemical methods can be found among them. Also, nanotechnology offers process improvements to enology. This article describes the past and the current wine stabilization methods and summarizes the directions for developing this interdisciplinary branch of knowledge.</p> </trans-abstract>ARTICLEtrueółczesne Metody Identyfikacji Białkowych Antygenów Szczepionkowych<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Advancements in modern genomics driven by the continuous DNA sequencing of complete microbial genomes, including pathogenic microorganisms, have revolutionised the approach to the process of designing new generation vaccine antigens. Genomic data is the source of hypotheses about potential antigen immunogenicity, reversing the standard science research process. As a result, it is possible to analyse thousands of genes regardless of their <italic>in vivo</italic> expression levels. On this basis, we can choose the pool of protein candidates to examine further, mapping their epitopes recognised by the elements of the human immune system. The acquired information on the structure of the selected antigen and its interactions with the immune system may be used to design and synthesise new immunogenic molecules, optimising time and resources needed to introduce new vaccines to the market.</p> </trans-abstract>ARTICLEtrueływania Pomiędzy Małymi, Regulatorowymi RNA a Dwuskładnikowymi Systemami Transdukcji Sygnału u Bakterii Gram-Ujemnych<trans-abstract xml:lang="en"> <title style='display:none'>Summary</title> <p>Small, regulatory RNA molecules (sRNAs) together with two-component signal transduction systems (TCSs) are part of extensive networks for controlling bacterial gene expression. By interacting with each other, they ensure a swift and precise response of bacteria to changing living conditions. They control many processes, including the composition of the bacterial cell envelope and biofilm formation. Very often, sRNAs are the missing links between TCSs and their target genes or other regulatory systems in response to complex environmental stimuli. TCS-sRNA interaction is now considered a global regulatory feature in many prokaryotes. Learning about these control mechanisms paves the way to developing new strategies to combat pathogens.</p> </trans-abstract>ARTICLEtrueóżne Oblicza Sławnego Odkrywcy Pamięci Ludwika Pasteura w 200. Rocznicę Urodzin<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Louis Pasteur is considered one of the world’s greatest scientists. However, some cracks in the Pasteur’s monument have been spotted. His character and certain activities are subject to criticism or at least controversy. The review of achievements of the French scientist, contained in this article, prepared on the occasion of the bicentenary of his birth, shows that, despite the accusations formulated from different sides, Pasteur fully deserves to be called a “benefactor of mankind”.</p> </trans-abstract>ARTICLEtrue Pathogens of the Genus in Louis Pasteur Days and in 200th Anniversary of his Birth<abstract> <title style='display:none'>Abstract</title> <p>This year we are celebrating the 200th anniversary of the birth of Louis Pasteur, one of the fathers of microbiology. Interestingly, the time when Pasteur disproved the doctrine of „spontaneous generation” and announced the “germ theory of disease” coincides with the discovery of <italic>Cryptococcus neoformans</italic> and its role in cryptococcosis. Today, only in the realm of guesswork can remain the correct answer to the question „whether the observed parallelism of these events was accidental?” or „whether Pasteur’s discoveries constituted a solid foundation of the research on the etiological factors of cryptococcosis?”. Until recently, it might seem that all major virulence factors of pathogenic fungi of the <italic>Cryptococcus</italic> species complex have been thoroughly described. Meanwhile, the simultaneous publication in 2018 of three <italic>in vitro</italic> protocols for the induction of Titan cells, also known as giant cells, opened up new possibilities for research on the relatively uncharacterized virulence factor that is crucial for <italic>Cryptococcus</italic> spp. Research on the titanization process makes us realize how little we know about the virulence factors of these fungi, and how much more can be improved in the context of the treatment and prevention of cryptococcosis. The following review is not only a historical outline of research on <italic>Cryptococcus</italic> spp. and cryptococcosis, but also synthetically describes the virulence factors of these basidiomycetous yeasts, with particular emphasis on the titanization process. The phenomenon of titanization as a process of a specific morphological transformation, like Titan cells, are completely new terms in Polish literature, which will be introduced to readers here. We live in a post-antibiotic era where the lack of effective and non-toxic drugs affects patients all over the world. Specifically, the availability of only fluconazole, amphotericin B and flucytosine in therapy of cryptococcosis constitutes a significant limitation. For this reason, research on the virulence factors of <italic>Cryptococcus</italic> spp. will allow to find new effective antimycotics, including inhibitors of the titanization process.</p> </abstract>ARTICLEtrue Oparzeniowa – Procesy Jej Rozwoju Oraz Wybrane Czynniki Etiologiczne Zakażenia<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Although the topic of burns appears to be relatively well understood in the literature, there is still an apparent discontinuity in the understanding of the correlation of the pathomechanism of thermal injury with the key issue of infection within it. From the analysis of the literature, an intriguing picture emerges for both clinicians and microbiologists. Microbiological diagnosis is extremely important in burn wound infections. The correct sampling and performance of microbiological cultures allows for the identification of the etiological agent of infection and the appropriate choice of targeted antibiotic therapy based on the results of microbiological tests. This is particularly important in the era of increasing resistance of microorganisms and frequent isolation of multi-drug resistant strains. A burn, especially extensive, is a unique environment which, together with ill-considered or ineffective therapy, determines the acquisition of antibiotic resistance in microorganisms. The consequence of physiological defense of the body against injury leads to a situation where in the center of the burn wound antimicrobials may not reach MIC/MBC, which drastically reduces the chances of therapeutic success.</p> </trans-abstract>ARTICLEtrue i Analizy Genomiczne Bakterii z Rodzaju<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Bacteria belonging to the genus <italic>Azotobacter</italic> are the subject of many studies conducted both in Poland and around the world. The interest in this group of bacteria is largely related to their properties being very useful for agriculture. Recent studies are based on advanced molecular methods and genomic sequence of the two species: <italic>Azotobacter vinelandii</italic> and <italic>Azotobacter chroococcum</italic>. In 2009, Setubal et al. published the complete genome sequence of <italic>Azotobacter vinelandii</italic> DJ, while the full sequence of <italic>Azotobacter chroococcum</italic> 8003 genome was published by Robson <italic>et al</italic>. in publication from 2015. Both bacteria have a single, circular chromosome of 5,355,318 bp and 5,192,291 bp respectively. Understanding and comparing the genome sequence of <italic>Azotobacter vinelandii</italic> DJ and <italic>Azotobacter chroococcum</italic> 8003 answered many questions about the evolution, diversity and location of these bacteria in the environment. The sequencing of a larger number of genomes of other <italic>A. chroococcum</italic> and <italic>A. vinelandii</italic> strains would bring many benefits and would help to organize the existing knowledge about them.</p> </trans-abstract>ARTICLEtrue – Virulence Factors and Epidemiology of Infections<abstract> <title style='display:none'>Abstract</title> <p><italic>Acinetobacter baumannii</italic> is a Gram-negative saprophytic rod inhabiting both moist niches and dry surfaces. The wide spread of the microbe in the environment by means of minimal nutritional requirements and exceptional survival capabilities give the opportunities to occupy hospital niches, and thus to create threats for hospitalized patients. This bacterium may be a part of the human microbiota as an opportunistic pathogen which upon the host’s weakening, causes less or more serious diseases. <italic>A. baumannii</italic> is an etiological factor of ventilator-associated pneumonia, which is especially dangerous for patients in intensive care units (in Poland every fifth patient suffers from such infection). Due to the increasing multidrug resistance of <italic>A. baumannii</italic>, this bacterium belongs to the group of priority pathogens. Fighting such dangerous bacteria is difficult due to their natural resistance as well as acquired resistance mechanisms in response to environmental threats. The unique ability of <italic>A. baumannii</italic> to cause diseases and acquire resistance to numerous antibiotics, make it necessary to control and prevent these infections.</p> </abstract>ARTICLEtrue European Medicines Agency Approved the New Antibacterial Drugs – Response to the 2017 Who Report on the Global Problem of Multi-Drug Resistance<abstract> <title style='display:none'>Abstract</title> <p>The growing problem of antimicrobial resistance has been classified by the World Health Organization (WHO) as one of the top ten threats to mankind. In a special report published in 2017, the WHO presented a list of microorganisms for which the search for new therapeutic options is a priority. The highest (critical) priority was given to the search for new antibiotics active against carbapenem-resistant strains of <italic>Acinetobacter baumannii</italic> and <italic>Pseudomonas aeruginosa</italic> as well as against carbapenem- and third-generation-cephalosporin-resistant <italic>Enterobacterales</italic> strains (so-called critical priority pathogens). Whereas the second (high) priority was given among others to the search for new antibiotics active against methicillin- and vancomycin-resistant strains of <italic>Staphylococcus aureus</italic> (MRSA and VRSA) and vancomycin-resistant strains of <italic>Enterococcus faecium</italic> (VRE). Since the publication of the WHO report the European Medicines Agency has approved 6 novel, broad-spectrum antibiotics, from 6 different groups, addressing the priority pathogens to a different extent. Two of them are new combinations of carbapenems with non-β-lactam inhibitors of β-lactamases (active also against carbapenemases), belonging to two novel groups of inhibitors: diazabicyclooctanes (relebactam, combined with imipenem) and boronates (vaborbactam, combined with meropenem). The third new drug is a siderophore cephalosporin (cefiderocol) with an innovative mechanism of penetration into the bacterial cell. The next two antibiotics are the new fluoroquinolone (delafloxacin) and the new tetracycline (eravacycline), designed and synthesized to be more active than older members of these groups. The last innovative antibiotic is lefamulin – the first pleuromutilin approved for systemic use in humans. New approvals have expanded the number of available therapeutic options in the treatment of complicated urinary tract infections (meropenem/vaborbactam, cefiderocol), complicated intra-abdominal infections (meropenem/vaborbactam, eravacycline), nosocomial pneumonia (meropenem/vaborbactam, imipenem/relebactam), acute bacterial skin and skin structure infections (delafloxacin) and community-acquired pneumonia (lefamulin).</p> </abstract>ARTICLEtrueływ Higieny Rąk Personelu Medycznego na Transmisję Czynników Etiologicznych Zakażeń Związanych z Opieką Zdrowotną<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Appropriate hand washing and disinfection procedures among medical employees are one of the basic principles of preventing healthcare-associated infections (HAI), which can significantly extend hospitalization and generate higher costs. The aim of the study was to review the available literature on the sources and transmission of HAI in the context of medical staff hand hygiene, to evaluate, whether these procedures are performed correctly and whether the hands and nails contribute to the transmission of microorganisms in the hospital environment. Medical literature was searched in PubMed and Google Schoolar databases by entering appropriate keywords. The collected literature clearly show how important is the correct hand washing procedure, short and unpainted nails and no jewellry on the hands of hospital staff in breaking the chain of nosocomial infections.</p> </trans-abstract>ARTICLEtrue OF: Sebastian Gnat, Dominik Łagowski, Mariusz Dyląg, Aneta Nowakiewicz: Ludzki mykobiom w stanach normobiozy i dysbiozy– charakterystyka i metody analizy. OF: Sebastian Gnat, Dominik Łagowski, Aneta Nowakiewicz, Mariusz Dyląg: Molekularne metody diagnostyki dermatomykoz – przegląd dostępnych technik oraz ocena ich zalet i wad w implementacji do rutynowego stosowania. OF: Dominik Łagowski, Sebastian Gnat, Aneta Nowakiewicz: Mechanizmy powstawania oporności dermatofitów na substancje przeciwgrzybicze. OF: Sebastian Gnat, Dominik Łagowski, Aneta Nowakiewicz: Zastosowanie techniki MALDI-TOF MS do identyfikacji dermatofitów. OF: Sebastian Gnat, Aneta Nowakiewicz, Przemysław Zięba: Taxonomy of dermatophytes – the classification systems may change but the identification problems remain the same. Review of Probiotic Applications in Poultry: Improving Immunity and Having Beneficial Effects on Production and Health<abstract> <title style='display:none'>Abstract</title> <p>A new class of feed additives and nutritional supplements, known as probiotics, include bacterial, fungal, and yeast cultures from various sources. Overall, probiotics are believed to promote the health and well-being of animals, birds, and humans in a variety of settings. Incorporating probiotics into the diets of cattle and poultry has been demonstrated to improve growth, feed conversion efficiency, immunological responses, and the animal's ability to manage enteric infections. The use of probiotic-enriched chicken feed has been shown to enhance egg production by as much as 30% among laying chickens. Probiotics may be used to fight off harmful microorganisms, create antibacterial compounds (such as bacteriocins or colicins), and alter the immunological response of the host, according to the National Institutes of Health. Pathogenic microbial strains such as <italic>Lactobacillus</italic>, <italic>Streptococcus</italic>, <italic>Bacillus</italic>, <italic>Enterococcus</italic>, <italic>Pediococcus</italic>, <italic>Aspergillus</italic>, and <italic>Saccharomyces</italic> are employed in the making of chicken products. The use of subtherapeutic doses of antimicrobial agents, including antibiotics, to combat or remove harmful bacteria and promote animal growth and feed efficiency has resulted in the accumulation of antibiotic residues in animal feed as well as the emergence of drug-resistant microbes in the feed supply chain. As a result of public health concerns, there has been a renewed emphasis on the use of probiotics in chicken production rather than antibiotics in recent years. This research examines the effects of probiotics and direct-fed microorganisms (DFM) on chicken health and performance, with a particular emphasis on the favourable effects they have on poultry health and performance.</p> </abstract>ARTICLEtrue I „Efekt Czerwonej Królowej”<trans-abstract xml:lang="en"> <title style='display:none'>Abstract</title> <p>Whooping cough is a contagious and typically childhood disease transmitted via droplets. Pertussis is especially dangerous for infants, but adults have become more susceptible. A pathognomonic symptom of pertussis is a severe spasmodic and unproductive cough that worsens at night and is accompanied by vomiting, apnea and cyanosis. The symptoms among vaccinated children, adolescents and adults, are milder, less characteristic, and therefore more difficult to diagnose. Whole-cell pertussis vaccine (DTwP) has been highly effective in reducing morbidity and mortality. However, in many countries DTwP vaccines, due to their reactogenicity, have been completely or partly replaced, by acellular pertussis vaccines (DTaP) that contain several purified bacterial protein antigens. In spite of the sustained high coverage of vaccinations, there is an increase of whooping cough cases in all age groups. The main cause of the increase is the lack of full protection from acellular vaccine in preventing transmission of <italic>Bordetella pertussis</italic>, which is the main etiological factor of whooping cough. Moreover, new diagnostic methods allow to identify other <italic>Bordetella</italic> species that cause pertussis-like symptoms, i.e. <italic>B. parapertussis</italic> and <italic>B. holmesii</italic>. The currently used vaccines do not provide a cross-protection against <italic>B. holmesii</italic> that has now become the second etiological factor of pertussis. Imperfections of existing vaccines are the reason for an intense development of improved anti-pertussis vaccines. Several research directions can be distinguished, such as identifying new components, designing an acellular vaccine based on the outer membrane vesicles or the renewed interest in whole cell vaccines.</p> </trans-abstract>ARTICLEtrue