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Removal of antibiotics from wastewater by advanced oxidation technologies
Macsek, Tomáš ; Rusník,, Igor (referee) ; Bodík,, Igor (referee) ; Hlavínek, Petr (advisor)
Antibiotics are substances that inhibit the growth of microorganisms and are widely used in modern medicine. High consumption of antibiotics correlates with their elevated occurence in sewage systems, from where they are further released into the environment. The threat of their occurrence in the environment is in triggering the formation and spread of antibiotic resistance. This thesis focuses on the removal of selected antibiotics and partly on the antibiotic resistance from wastewater by advanced oxidation processes (AOPs). AOPs are based on the creation of highly reactive hydroxyl radicals, which are able to oxidize even highly persistent substances. The thesis focuses on the purification of effluents from municipal wastewater treatment plants (WWTP), which are identified as the main source of pharmaceutical pollution in the environment, by AOPs mainly based on ozonation. These processes were tested under laboratory conditions on model water as well as under real conditions as the tertiary stage of the treatment at Brno-Modřice WWTP under various operating states. As the results of the performed experiments show, it could be concluded that the studied AOPs are capable of effective degradation of studied antibiotics from the treated medium. Under real conditions, the antibiotics sulfamethoxazole, trimethoprim, azithromycin and clarithromycin were monitored. Output concentrations in each operational state were achieved to be below the limit of detection for all four antibiotics. The application of AOPs based on ozonation as the tertiary step of the treatment also had a positive effect on the reduction of microbial contamination and antibiotic resistance. Within the pilot plant experiments, a reduction of up to 4 orders of magnitude of E.coli, coliform microorganisms and a reduction of their resistant strains in the range of 1.4 - 4.0 logs were observed, compared to the effluent from the WWTP.
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Výskyt antimikrobiální rezistence u streptokoků (převážně beta-hemolytických) z ran pacientů
Kuropata, Daniel
Recently, a frequent occurrence of antibiotic resistance has been observed, and is still increasing. Therefore, it is important to constantly monitor this resistance, which was the aim of this work for Streptococcus genera. The literature review is focused on the selected species of streptococci (S. agalactiae, S. dysga-lactiae subsp. equisimilis, S. pyogenes, S. mitis and S. oralis), antibiotics, including their mechanism of action, and antibiotic resistance with an emphasis on its emergence, spread, mechanisms, determining genes and the risks it presents. In the experimental part, the occurrence of resistance in streptococci (especially beta-haemolytic) isolated from patients’ wounds at the Trauma Hospital in Brno was monitored. For this purpose, determination of the minimum inhibitory concentration (MIC), analysis of the resistance phenotype to macrolides, lincosamides and streptogramin B (MLS) using the D-test and resistance gene screening by polymerase chain reaction (PCR) were used. Among the 31 clinical isolates the prevalence of resistance to cotrimoxazole (96.8%), ciprofloxacin (71%), tetracycline (29%), erythromycin (25.5%), clidamycin (16 .1%), ampicillin (3.2%) and oxacillin (3.2%) was found by using MIC. Resistance to chloramphenicol, gentamicin, vancomycin, teicoplanin, linezolid, tigecycline and nitrofurantoin has not been detected. The D-test was performed with erythromycin-resistant isolates. The constitutive (cMLS) phenotype was detected in 62.5% of erythromycin-resistant isolates, inducible (iMLS) in 25% and M phenotype in 12.5%. The PCR method confirmed the presence of selected resistance genes, namely ermA (16.1%), ermB (6.5%), mefA (3.2%), tetO (3.2%), tetM (25.8%) and intTn (32.3%). This study demonstrated that all streptococcal isolates from patients’ wounds are resistant to some of the tested antibiotics. Moreover, multiresistance was detected in some isolates.
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Horizontální přenos genů rezistence mezi bakteriemi
Valach, Radek
Transfer of bacterial antibiotic resistence is highly discussed topic in past years. Its spreading is reason of creating super-resistant bacterial strains, that are resistant to a wide range of conventionally used drugs. Zinc oxide, used in pig farming as a feed supplement, has in recent years replaced antibiotics, given to prevent gastrointestinal disease and to promote growth. These substituent may increase transfer of genetic elements carying antibiotic resistence genes. This thesis is focussed on possible influence of zinc oxide and its nanoparts on Enterococcus faecalis bacteria. The aim of this work was to investigate whether the action of ZnO and ZnONPs would increase the transfer of a resistance gene plasmid between bacteria through the process of conjugation.
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Antibiotic resistance profile determination in hybrid assembled bacterial genomes
Dzurčaninová, Natália ; Škutková, Helena (referee) ; Nykrýnová, Markéta (advisor)
Antibiotická rezistencia je vážny problém vo väčšine spôsobený zmenami v bakteriálnom genóme. Získavanie a uchovávanie spoľahlivých bakteriálnych genomických dát je preto nevyhnutné pre štúdium mechanizmov a prenosu antibiotickej rezistencie. Táto práca popisuje bakteriálny genóm, antibiotickú rezistenciu a nástroje pre jej identifikáciu spolu s procesmi nevyhnutnými pre zisk genómov, sekvenáciu a skladanie. Sústreďuje sa na hybridné skladanie genómov spravidla vysoko rezistentných baktérií Klebsiella pneumoniae a ich nasledujúcich analýz. Cieľom týchto analýz je skonštruovať profily antibiotických rezistencií a určiť fylogenetickú príbuznosť genómov.
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Antibiotic resistance profile determination in hybrid assembled bacterial genomes
Dzurčaninová, Natália ; Škutková, Helena (referee) ; Nykrýnová, Markéta (advisor)
Antibiotická rezistencia je vážny problém vo väčšine spôsobený zmenami v bakteriálnom genóme. Získavanie a uchovávanie spoľahlivých bakteriálnych genomických dát je preto nevyhnutné pre štúdium mechanizmov a prenosu antibiotickej rezistencie. Táto práca popisuje bakteriálny genóm, antibiotickú rezistenciu a nástroje pre jej identifikáciu spolu s procesmi nevyhnutnými pre zisk genómov, sekvenáciu a skladanie. Sústreďuje sa na hybridné skladanie genómov spravidla vysoko rezistentných baktérií Klebsiella pneumoniae a ich nasledujúcich analýz. Cieľom týchto analýz je skonštruovať profily antibiotických rezistencií a určiť fylogenetickú príbuznosť genómov.
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Cellular factors influencing the antibiotic resistance by ABC-F proteins
Kýr, Jan ; Balíková Novotná, Gabriela (advisor) ; Dolejšová, Tereza (referee)
Antibiotic resistance is one of the main problems modern medicine has to face. In order to control it, it is important first to understand the mechanisms by which resistant pathogens bypass antibiotic treatment. One of the important protein families conferring resistance to 50S binding antibiotics is the ARE ABC-F protein family. A member of this protein family is the MsrA protein, which confers resistance to 14- and 15-membered macrolides. Loss-of-function mutations in the non-essential chaperone ClpX were found to a significant ly enhance the action of the MsrA protein. This leads to the significant increase in the resistance conferred by this protein. The exact mechanism by which ClpX affects MsrA function is still unknown. In this the diploma thesis was demonstrated that chaperone protein ClpX affects the resistance to erythromycin conferred by MsrA protein, due to the interaction with an unknown essential protein, which is mediated by a functional N-terminal zinc-binding domain of the chaperone. Furthermore, it was demonstrated in this work that loss of GluTR function influence the MsrA ability to confer resistance. The results of this work will bet he basis for further reasearch, which will lead to a more detailed understanding of the mechanism of resistance conferred by these proteins and...
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Faktory ovlivňující informovanost veřejnosti o antibiotikách
TUNKOVÁ, Barbora
Adequate knowledge of antibiotic use is one of the main prerequisites for preventing the spread of antibiotic resistance, which has become a public health threat in today's world. The aim of this study was to assess the impact of gender, education, and industry (food industry, agriculture, or healthcare) on awareness of antibiotics and antibiotic resistance through a questionnaire survey (n=799) and to compare antibiotic consumption (defined daily dose per 1000 inhabitants per year, DDD) in 16 European countries for the reporting period. Women were found to be more knowledgeable about the effects of antibiotics than men (p <0,0010). There was a statistically significant effect of education level and relevant discipline on knowledge regarding antibiotic resistance (p <0,0010). The highest average antibiotic consumption (21.97 DDD) was found in southern Europe, while the lowest antibiotic consumption was found in the Nordic countries (15,62 DDD).
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Diagnostics and therapy of polyresistant bacteria in the Hospital Havlíčkův Brod
KOSTKOVÁ, Monika
Antibiotic resistance is a problem not only in our country but also in the world. The incidence of polyresistant bacterial species, which cause serious and difficult-to-treat infections, is increasing. This issue has implications for both patients' health and healthcare costs. The practical part of my bachelor thesis was performed in the Laboratory of clinical mikrobiology (ONHB). Samples were taken from ONHB, from the Psychiatric Hospital and from general practitioners from around Havlíčkův Brod. In my work, I visited strains of Klebsiella pneumoniae and Pseudomonas aeruginosa, which are often the cause of nosocomial infections. The first step was the correct isolation and diagnosis of bacteria and examination of the susceptibility of bacteria to antibiotics, where I used the disk diffusion method, the minimum inhibitory concentration and methods for the detection of broad-spectrum -lactamases. The aim of this work was to determine the representation of the number of these bacteria in the community and in the hospital environment, where I assumed that the incidence of resistant bacteria in the hospital environment is higher. I also dealt with the development of resistance of these bacteria to given antibiotics in the period 2017-2022. In conclusion, I drew attention to the correct principles of antibiotics and thus to the prevention of antibiotic resistance, as well as the possibilities of prevention and treatment of nosocomial infections.
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Competition of cells within the population of yeast colony
Očková, Veronika ; Váchová, Libuše (advisor) ; Gášková, Dana (referee)
Competition is a very important natural phenomenon, which causes the rivalry of organisms, in cases such as space limitation or lack of nutrients. It occurs mainly in situations where organisms, including microorganisms live in large populations. Multicellular yeast colonies represent an example of such a population. After the population of yeast cells spends nutrients from the environment, the cells in colonies are able to respond to these changes by production of ammonia functioning as a signaling molecule. Subsequently, the cells are able to change their morphology and metabolism and, dependently on their location within the colony, to create a subpopulation of cells with specific characteristics and functions. It is likely that in the case of mixed colonies formed by the two different strains, a competition between the cells of these two strains could exist. Such rivalry can result in changes in the ratio of cells of the two strains within the colony population, so that the cells of one strain outweigh the other. In this diploma thesis, I compared the growth and development of giant colonies and competition between the cells of selected pairs of strains forming mixed colonies. I focused on the parental strain Saccharomyces cerevisiae BY and its variants labeled with fluorescent proteins. For...
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