Surface mucus of a freshwater fish, Alburnus alburnus (bleak), caught from Lake Mogan, situated in south of Ankara, was collected in different seasons. The total cultivable bacteria were enumerated by spread plate method on nine different media. Bacteria were isolated based on colony morphologies and pigmentation. A total of sixty bacterial isolates obtained. The mucus-dwelling bacteria were first tested for resistance against ampicillin and kanamycin / then streptomycin and chloramphenicol were added to the experimental set up. The resistance levels of isolates were determined in terms of four antibiotics by tube dilution method. About 90% of the isolates were resistant to chloramphenicol, about 84% to kanamycin, about 88% to streptomycin and about 98% to ampicillin. These high levels of antibiotic resistance are rather interesting from a standpoint that the lake has no record of antibiotics exposure of any sort. The plasmid isolations were carried out to determine if the multiple antibiotic resistance could be attributed to plasmids for starting assumption. But we found no direct relationship between the presence of plasmids and multiple antibiotic resistance. Our study indicated that multiple antibiotic resistance at high levels is among the current phenotypes of the fish mucus-dwelling bacterial populations in Lake Mogan.

To gain a better understanding of contaminating bacteria in bioethanol industry, we profiled the bacterial community structure in corn-based bioethanol fermentations and evaluated its correlation to environmental variables. Twenty-three batches of corn-mash sample were collected from six bioethanol facilities. The V4 region of the collective bacterial 16S rRNA genes was analyzed by Illumina Miseq sequencing to investigate the bacterial community structure. Non-metric multidimensional scaling (NMDS) ordination plots were constructed to visualize bacterial community structure groupings among different samples, as well as the effects of multiple environmental variables on community structure variation. Our results suggest that bacterial community structure is facility-specific, although there are two core bacterial phyla, Firmicutes and Proteobacteria. Feedstock, facility, and fermentation technology may explain the difference in community structure between different facilities. Lactic acid, the most important environmental variable that influences bacterial community structure grouping, could be utilized as an indicator of bacterial contamination. We also identified genes responsible for the multiple antibiotic-resistance phenotype of an Enterobacter cloacae strain isolated from a bioethanol fermentation facility. We performed PCR assays and revealed the presence of canonical genes encoding resistance to penicillin and erythromycin. However, a gene encoding resistance to virginiamycin was not detected.

Bakgrund: ESBL är ett enzym som kan produceras av bakterier i tarmens normalflora och gör bakterien motståndskraftig –resistent- mot många antibiotika. För den enskilde individen får det konsekvenser vid en infektion orsakad av ESBL-bildande tarmbakterier, och då behandling krävs. De som infekteras med dessa bakterier riskerar att svara dåligt på behandling med våra vanligaste antibiotika, och det kan krävas inläggning på sjukhus även vid banala infektioner. Syfte: Att fördjupa kunskapen om vad det innebär för den enskilda individen att drabbas av ESBL-bildande tarmbakterier. Metod. En modifierad variant av Grounded Theory användes som analysmetod av sju öppna intervjuer. Resultat: I analysen växte kärnkategorin Att bli utkastad i det skrämmande och okända utan karta och kompass fram. Samtliga informanter upplevde att de fått bristande information, eller ingen information alls om sin diagnos. Informationsvägen från läkaren var antingen via telefon eller genom ett brev via posten. Konsekvensen blev att det uppstod många tankar och funderingar efteråt, och det innefattade även frågan om hur man blivit smittad; genom sjukvården eller om de själva orsakat att bli smittade. I mötet med sjukvården upplevdes att okunskapen hos personalen i vissa fall orsakade stigmatisering. Här förekom såväl extrema hygienåtgärder i form av “skyddsmundering“ som alltför bristande hygienrutiner. Därutöver framkom också upplevda attitydproblem från personalens sida, nonchalans, bristande förståelse, ingen villighet eller tid att svara på frågor. Allt detta ledde till att informanterna i sin egen vardag fick ta saken i egna händer. Samtliga försökte skaffa sig information på annat sätt, exempelvis via internet. I oron för att smitta andra konstruerades egna åtgärder av kvinnorna i studien, exempelvis att instruera andra om handtvätt, att själv desinfektera föremål vid vårdbesök och i bostaden, att inte åka med tunnelbana eller buss, att inte umgås med andra och att själv uppleva informationsplikt om sin smitta. Männen i studien vidtog, trots bristande eller ingen information alls, inte några speciella åtgärder i sitt vardagsliv, de fortsatte att leva som tidigare. Ingen ville oroa sina anhöriga/närstående. Det förekom att barnen ej informerats alls om diagnosen. Konklusion: För att kunna hantera sin livssituation är det av stor betydelse att den som drabbas av en ESBL-bildande bakterie får en god information av patientansvarig läkare. / Background: Extended spectrum beta lactamase (ESBL), an enzyme produced by bacteria in normal intestinal flora, renders such bacteria resistant to many antibiotics. Some patients infected with ESBL respond poorly to antibiotic treatment, and even trivial infections may require hospitalization.Purpose: To increase understanding of the emotional impact of ESBL-producing intestinal bacteria.Method: This study used a modified version of grounded theory during seven open interviews to analyze coping mechanisms for ESBL infection.Results: Our analysis identified a core category (i.e., being thrown into scary and unknown territory without a map and compass). All respondents felt they received no or insufficient information about the diagnosis, and reported that any information they did receive arrived only by phone or letter. Consequently, respondents questioned whether they had been infected through medical care or through their own actions. They believed that lack of knowledge and attitude problems among healthcare providers (perceived as carelessness, lack of understanding, and unwillingness or lack of time to answer questions) stigmatizes patients. Such deficits led respondents to take matters into their own hands as they tried to obtain information by other means (e.g., the Internet). Respondents described extreme hygiene measures as a "protective suit" against inadequate hygiene. Female respondents constructed individual coping mechanisms (e.g., instructing others about hand washing technique, disinfecting objects during healthcare visits and at home, avoiding metro or bus travel, avoiding social interactions, and informing others of the infection). Conversely, male respondents took no special measures and lived as they did before infection. No one wanted to worry relatives/significant others, and no one told their children about the diagnosis.Conclusion: It is to important that attending doctors provide good information to individuals infected by ESBL-producing bacteria. Moreover, such individuals must develop good life management and coping skills. / <p>ISBN 978-91-86739-12-6</p>

Contamination of groundwater that is suitable for drinking is of growing concern as the water supply of South Africa is becomingincreasingly limited. This is especially the case in the North West province, with its semi – arid climate and variable rainfall patterns. The aim of the study was to evaluate the microbiological and physico – chemical qualities of groundwater obtained from selected DWA (Department of Water Affairs) monitoring boreholes in the Mooi River and Harts River catchment areas. Physico -chemical parameters included temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), sulphate and nitrate concentrations. Physical parameters were measured using a calibrated submerge-able multimeter and chemical parameters using specialised kits and a spectrophotometer. Microbiological parameters included heterotrophic plate counts and total and faecal coliform enumeration. Membrane filtration and culture based methods were followed for enumeration of bacteria. During the identification procedures multiplex PCR for E. coli identification and 16S rRNA gene sequencing for identification of heterotrophic plate count bacteria and amoeba resistant bacteria were used. For antibiotic resistance, the Kirby- Bauer (1996) disk diffusion method was used. During the warm and wet season high electrical conductivity and salinity were observed in the Trimpark (65.3 mS/m; 325 ppm), School (125.1 mS/m; 644 ppm), Warrenton (166.9 mS/m; 867 ppm) and Ganspan (83.3 mS/m; 421 ppm) boreholes. Warrenton borehole had a high sulphate level (450 mg/l) as well. High chemical oxygen demand was observed in the Blaauwbank (62 mg/l) and Warrenton (98.5 mg/l) boreholes. In the dry and cold season similar observations were made for the various boreholes. Electrical conductivity and salinity levels remained high for the Trimpark (70.1 mS/m; 427.5 ppm), School (127 mS/m; 645 ppm), Warrenton (173.3 mS/m; 896.5 ppm) and Ganspan (88.1 mS/m; 444.5 ppm) boreholes. Nitrate levels for the Trimpark (14.1 mg/l) and School (137 mg/l), as well as sulphate levels for the Warrenton (325 mg/l) borehole were also high. Total coliforms, faecal streptococci and HPC bacteria were enumerated from water samples from all boreholes, except Blaauwbank where no faecal streptococci were enumerated. Faecal coliforms were enumerated from 5 of the possible 7 boreholes during a warm and wet season (Trimpark – 42 cfu/100ml; School – 2 cfu/100ml; Cemetery – 175 cfu/100ml; Warrenton – 3.84 x 10³ cfu/100ml; Ganspan – 1.9 x 10³ cfu/100ml). Indicator bacteria (FC, TC, HPC) exceeded target water quality ranges (TWQR) for drinking water in each case. During the cold and dry sampling season, faecal coliforms were enumerated mainly from the Trimpark (11 cfu/100ml) borehole. Total coliforms, faecal streptococci and HPC bacteria were enumerated from all the boreholes, except for Blaauwbank that contained no faecal streptococci or total coliforms. Enumerated indicator bacteria levels again exceeded TWQR for domestic use. Total coliform counts for the Pad dam borehole, however, complied with TWQR for domestic use. Identified E. coli were resistant to Erythromycin, Cephalothin and Amoxicillin and susceptible to Ciprofloxacin. Escherichia coli isolated from the Mooi River catchment shared the same antibiotic resistance phenotype. The most abundant HPC bacterial genus identified was Pseudomonas spp. (7 isolates). Opportunistic pathogens isolated included Pseudomonas aeruginosa, Acinetobacter, Aeromonas, Alcaligenes, Flavobacterium, Bacillus cereus and Mycobacterium spp. Varying degrees of antibiotic resistance were observed. Generally, the same pattern between the same genera were observed. All HPC isolates were resistant to Cephalothin and Amoxicillin and a lower degree Erythromycin and Streptomycin. The most abundant amoeba resistant bacteria was identified as Pseudomonas spp. Other isolates included Alcaligenes faecalis and Ochrobactrum sp. and Achromobacter sp. All of these are opportunistic pathogens, except for Achromobacter. Resistance to more antibiotics (Streptomycin, Chloramphenicol, Cephalothin, and Amoxicillin) was observed in ARBs compared to HPC (Cephalothin, Amoxicillin) from bulk water from the same borehole. The water of all the aquifers sampled is of very poor physico - chemical or microbiological quality or both. Water may be used for irrigation or livestock watering only in the case where these boreholes comply with TWQR for said purposes. Results obtained indicate that the groundwater is faecally contaminated. Amongst the bacteria, opportunistic pathogens displaying various degrees of antibiotic resistance were frequently isolated. These results indicate health risks if untreated groundwater is consumed. Therefore groundwater needs to be treated before distribution especially if the water is for human consumption. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

Contamination of groundwater that is suitable for drinking is of growing concern as the water supply of South Africa is becomingincreasingly limited. This is especially the case in the North West province, with its semi – arid climate and variable rainfall patterns. The aim of the study was to evaluate the microbiological and physico – chemical qualities of groundwater obtained from selected DWA (Department of Water Affairs) monitoring boreholes in the Mooi River and Harts River catchment areas. Physico -chemical parameters included temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), sulphate and nitrate concentrations. Physical parameters were measured using a calibrated submerge-able multimeter and chemical parameters using specialised kits and a spectrophotometer. Microbiological parameters included heterotrophic plate counts and total and faecal coliform enumeration. Membrane filtration and culture based methods were followed for enumeration of bacteria. During the identification procedures multiplex PCR for E. coli identification and 16S rRNA gene sequencing for identification of heterotrophic plate count bacteria and amoeba resistant bacteria were used. For antibiotic resistance, the Kirby- Bauer (1996) disk diffusion method was used. During the warm and wet season high electrical conductivity and salinity were observed in the Trimpark (65.3 mS/m; 325 ppm), School (125.1 mS/m; 644 ppm), Warrenton (166.9 mS/m; 867 ppm) and Ganspan (83.3 mS/m; 421 ppm) boreholes. Warrenton borehole had a high sulphate level (450 mg/l) as well. High chemical oxygen demand was observed in the Blaauwbank (62 mg/l) and Warrenton (98.5 mg/l) boreholes. In the dry and cold season similar observations were made for the various boreholes. Electrical conductivity and salinity levels remained high for the Trimpark (70.1 mS/m; 427.5 ppm), School (127 mS/m; 645 ppm), Warrenton (173.3 mS/m; 896.5 ppm) and Ganspan (88.1 mS/m; 444.5 ppm) boreholes. Nitrate levels for the Trimpark (14.1 mg/l) and School (137 mg/l), as well as sulphate levels for the Warrenton (325 mg/l) borehole were also high. Total coliforms, faecal streptococci and HPC bacteria were enumerated from water samples from all boreholes, except Blaauwbank where no faecal streptococci were enumerated. Faecal coliforms were enumerated from 5 of the possible 7 boreholes during a warm and wet season (Trimpark – 42 cfu/100ml; School – 2 cfu/100ml; Cemetery – 175 cfu/100ml; Warrenton – 3.84 x 10³ cfu/100ml; Ganspan – 1.9 x 10³ cfu/100ml). Indicator bacteria (FC, TC, HPC) exceeded target water quality ranges (TWQR) for drinking water in each case. During the cold and dry sampling season, faecal coliforms were enumerated mainly from the Trimpark (11 cfu/100ml) borehole. Total coliforms, faecal streptococci and HPC bacteria were enumerated from all the boreholes, except for Blaauwbank that contained no faecal streptococci or total coliforms. Enumerated indicator bacteria levels again exceeded TWQR for domestic use. Total coliform counts for the Pad dam borehole, however, complied with TWQR for domestic use. Identified E. coli were resistant to Erythromycin, Cephalothin and Amoxicillin and susceptible to Ciprofloxacin. Escherichia coli isolated from the Mooi River catchment shared the same antibiotic resistance phenotype. The most abundant HPC bacterial genus identified was Pseudomonas spp. (7 isolates). Opportunistic pathogens isolated included Pseudomonas aeruginosa, Acinetobacter, Aeromonas, Alcaligenes, Flavobacterium, Bacillus cereus and Mycobacterium spp. Varying degrees of antibiotic resistance were observed. Generally, the same pattern between the same genera were observed. All HPC isolates were resistant to Cephalothin and Amoxicillin and a lower degree Erythromycin and Streptomycin. The most abundant amoeba resistant bacteria was identified as Pseudomonas spp. Other isolates included Alcaligenes faecalis and Ochrobactrum sp. and Achromobacter sp. All of these are opportunistic pathogens, except for Achromobacter. Resistance to more antibiotics (Streptomycin, Chloramphenicol, Cephalothin, and Amoxicillin) was observed in ARBs compared to HPC (Cephalothin, Amoxicillin) from bulk water from the same borehole. The water of all the aquifers sampled is of very poor physico - chemical or microbiological quality or both. Water may be used for irrigation or livestock watering only in the case where these boreholes comply with TWQR for said purposes. Results obtained indicate that the groundwater is faecally contaminated. Amongst the bacteria, opportunistic pathogens displaying various degrees of antibiotic resistance were frequently isolated. These results indicate health risks if untreated groundwater is consumed. Therefore groundwater needs to be treated before distribution especially if the water is for human consumption. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

Formål: Formålet med dette studie var at udforske og beskrive hvordan sundhedspersonale opfatter og håndterer risiko for smittespredning, både hos isolationspatienter og patienter, som ikke er isoleret. Desuden var formålet at afdække, om en eventuel særlig opfattelseaf smitterisiko hos isolationspatienter påvirker sundhedspersonalets opfattelse af betydningen af de generelle infektionshygiejniske forholdsregler. Metode:Studiet er et kvalitativt studie, hvor det empiriske materiale blev indsamlet i otte fokusgruppeinterviews, hvor deltagerne var sundhedspersonale.Som analysemetode blev anvendtsystematisk tekstkondensering. Den konceptuelle ramme omfatter antibiotikaresistens i et folkesundhedsperspektiv, en beskrivelseaf rammerne for infektionsforebyggelse i Danmark samt en teoretisk ramme bestående af risikobegrebet, sundhedspædagogik og et perspektiv på samarbejde. Resultater:Studiet viste, at sundhedspersonalet vurderede smitterisikoforskelligt, både ved isolationspatienterog ved ikke-isolerede patienter. De opfattede, at deres hygiejne ved isolations-patienter var bedre, fordi de tænkte sig bedre om og arbejdede mere struktureret. Samarbejde var en vigtig motivationsfaktor for arbejdet på isolationsstuer. Hos ikke-isolerede patienter opfattede sundhedspersonalet det som risikosituationer, når patienter delte stue og toilet. De oplevede selv brist i egen smitteafbrydelse og at patienters og pårørendes adfærd udgjorde en smitterisiko. Sundheds-personalet læste og forholdt sig forskelligt til infektionshygiejniske forholdsregler, hvilket kunne give anledning til forvirring og misforståelser. Det blev betragtet som en udfordring at skulle forholde sig til,at viden og praksis ændrede sig over tid og at ny udvikling skabte nye infektionshygiejniske udfordringer. Konklusion:Sundhedspersonale opfatter smitterisiko forskelligt, både i forhold til smitterisiko ved isolerede og ikke-isolerede patienter og arbejdet med at pleje og behandle isolationspatienter kunne være forbundet med stor angst for at sprede smitte. Forskelle i videns-og erfaringsgrundlag samt individuelle risikovurderinger ses som medvirkende årsager til,at sundhedspersonale opfatter og håndterer smitterisiko forskelligt / Aim:This study aimed to explore and describe how healthcare workers (HCWs) perceive and handle the risk of infection in isolated and non-isolated patients.The study also sought to determinewhetherany specialperceived risk of infection in isolated patients affects how HCWsperceive the importance of general infection control measures. Method:This was a qualitative study. Data was collected from eight HCW focus groups and analyzed using a systematic textcondensation method. The conceptual framework includes antibiotic resistance in a public health perspective, adescription of the context of infection controland prevention in Denmark, a theoretical framework consisting of the concept of risk, health education and a perspective on cooperation. Results: The study showed that HCWsassessed risk differently inisolated and in non-isolated patients. HCWs perceivedthat they prevented infection more effectively in isolated patients, due to greater attentiveness and a more structured approach.Cooperation was an important motivation in isolation rooms. HCWsperceived special risk situations among non-isolated patients who shared rooms and toilets. The HCWs experienced flaws in their own infection control measures andin the behaviour of patients and their relatives. HCWs read and interpreted infection control protocols differently leading to confusion and misunderstandings. It was a challenge keeping up the changing of knowledge and practice over time as well as new development caused new infection control challenges. Conclusion:HCWsperceive the risk of infection differently in isolated and non-isolated patients. Further, HCWs often associatethe work of caring for and treating isolated patients with fear of spreading infection. Differences in knowledge base, experience level and individualrisk assessments contribute to the explanation of differing perceptions and approaches to handle infection control / <p>ISBN 978-91-86739-49-2</p>

As one of the mechanisms of antibiotic resistance, bacteria use several families of membrane-embedded α-helical transporters to remove cytotoxic molecules from the cell. The small multidrug resistance protein family (SMR) is one such group of drug transporters that because of their relative small size [ca. 110 residues with four transmembrane (TM) helices] must form at the minimum dimers to efflux drugs. We have used the SMR homologue Hsmr from Halobacterium salinarum to investigate the oligomerization properties of the protein family at TM helix 4. We produced point mutations along the length of the TM4 helix in the full length Hsmr protein and assayed their dimerization and functional properties via SDS-PAGE and bacterial cell growth assays. We found that Hsmr forms functionally dependent dimers via an evolutionarily conserved 90GLxLIxxGV98 small residue heptad repeat. Upon investigation of the large hydrophobic residues in this motif by substituting each large residue to Ile, Leu, Met, Phe, and Val, we determined that Hsmr efflux function relies on an optimal level of dimerization. While some substitutions led to either decreased or increased dimer and substrate-binding strength, several Ile94 and Val98 mutants were equal to wild type dimerization levels but were nonfunctional, leading to the hypothesis of a mechanistic role at TM4 in addition to the locus of dimerization. The functionally sensitive TM4 dimer represents a potential target for SMR inhibition using a synthetic TM4 peptide mimetic. Using exponential decay measurements from a real-time cellular efflux assay, we observed the efflux decay constant was decreased by up to ~60% after treatment with the TM4 peptide inhibitor compared to control peptide treatments. Our results suggest that this approach could conceivably be used to design hydrophobic peptides for disruption of key TM-TM interactions of membrane proteins, and represent a valuable route to the discovery of new therapeutics.

Despite the large arsenal of antibiotics available on the market, treatment of bacterial infections becomes more challenging in view of the fact that microbes develop resistance against existing drugs. There is an obvious need for novel drugs acting on both old and new targets in bacteria. In this thesis we have employed a whole cell bacterial assay for screening and identification of type III secretion system (T3SS) inhibitors in Yersinia pseudotuberculosis. The T3SS is a common virulence mechanism utilized by several clinically relevant Gram-negative bacteria including Salmonella, Shigella, Pseudomonas aeruginosa, Chlamydiae and Escherichia coli. Several components in the T3SS have proved to be conserved and hence data generated with Y. pseudotuberculosis as model might also be valid for other bacterial species. We have screened a 9,400 commercial compound library for T3S inhibitors in Y. pseudotuberculosis using a yopE reporter gene assay. The initial ~ 30 hits were followed up in a growth inhibition assay resulting in 26 interesting compounds that were examined in more detail. Three of the most interesting compounds, salicylanilides, 2-hydroxybenzylidene-hydrazides and 2-arylsulfonamino-benzanilides, were selected for continued investigations. The inhibitor classes show different profiles regarding the effects on T3SS in Yersinia and their use as research tools and identification of the target proteins using a chemical biology approach will increase our understanding of bacterial virulence. The 2-hydroxybenzylidene-hydrazides have been extensively studied in vitro and show potential as selective T3S inhibitors in several Gram-negative pathogens besides Y. pseudotuberculosis. The data obtained suggest that this inhibitor class targets a conserved protein in the secretion apparatus. In cell-based ex vivo infection models T3SS was inhibited to the advantage of the infected eukaryotic cells. The salicylanilides and 2-arylsulfonamino-benzanilides have been further investigated by statistical molecular design (SMD) followed by synthesis and biological evaluation in the T3SS linked reporter gene assay. Multivariate QSAR models were established despite the challenges with data obtained from assays using viable bacteria. Our results indicate that this SMD QSAR strategy is powerful in development of virulence inhibitors targeting the T3SS.

O objetivo deste estudo foi caracterizar bactérias multirresistentes (MDR) isoladas de cavalos saudáveis (fezes) e doentes no Brasil e na França. De março de 2012 a dezembro de 2014, amostras clínicas coletadas de cavalos saudáveis e doentes no Brasil foram selecionadas para pesquisa da presença de bactérias MDR. A investigação sobre as amostras franceses foi restria a isolados de Escherichia coli (EC) recuperados a partir de amostras clínicas coletadas entre 2014 e 2015. Nos cavalos brasileiros, a análise de amostras de fezes de animais saudáveis revelou a presença de clones de EC não relacionados pertencentes aos filogrupos A, D ou B2 que carreavam genes como: blaCTX-M-1, blaCMY-2, qnr- e genes add-tipo (amino-transferases); enquanto que nos cavalos doentes foram encontradas EC, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa e Serratia marcescens carreando genes blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA metilase, qnr-tipo, aac(6´)-Ib-cr e aad-tipo. Nos cavalos doentes franceses de EC MDR foram positivas para CTX-M-1, seguido de M-2- e M-9. Estes resultados destacam a importância de cavalos como um novo reservatório de bactérias MDR. / The aim of this study was to characterize multidrug-resistant (MDR) bacteria isolated from healthy and infected horses in Brazil and France. From March 2012 to December 2014, clinical samples collected from healthy and infected horses, in Brazil, were screened for the presence of MDR bacteria. Investigation on French isolates was restricted to E. coli strains recovered from clinical samples collected between 2014 and 2015. In Brazilian horses, the analysis of fecal samples from healthy animals revealed the presence of clonally unrelated A, D or B2 phylogroups of E. coli strains carrying blaCTX-M-1, blaCMY-2, qnr- and aminoglycoside adenyl transferase (aad)-type genes, whereas in infected horses, E. coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Serratia marcescens isolates carrying blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA methylase, qnr-type, aac(6´)-Ib-cr and aad-type genes. In French infected horses, most MDR E. coli isolates were positive for CTX-M-1-, followed by CTX-M-2- and CTX-M-9-type extended-spectrum beta-lactamases. These results highlight the importance of horses as a new reservoir of MDR bacteria.

This study focuses on the question of the epidemiology of resistance to antibiotics in Acinetobacter baumannii, which is nowadays one of the most problematic bacterial patho- gens associated with failing antimicrobial therapy. Its aim was to define population-genetic properties, epidemiology and the nature of multidrug resistance for a sample of the current population of A. baumannii from Czechia. A total of 55 isolates were collected in eight medi- cal facilities in central Bohemia from October 2016 to May 2018. The isolates were assessed for their identity at the species, clonal and strain levels as well as resistance phenotype and genotype; they were classified into five clonal groups, each of which encompassed isolates that were likely to be epidemiologically related. The 55 isolates studied belonged, nearly exclusively, to global clone ECII, with 53 % of them forming a genetically relatively homoge- neous group characterized by extensive resistance to antibiotics (susceptible only to col- istin), the presence of genes encoding ArmA a OXA-23 (resistance to all aminoglycosides and carbapenems) and spread in all locations. The in-depth epidemiological analysis of isolates from the city of Příbram and its vicinity indicated the regional spread of two strains, one of which belonged to the...