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1.
BMC Microbiol ; 23(1): 207, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37528354

RESUMO

BACKGROUND: The emergence of antibiotic resistance in pathogenic bacteria has become a global threat, encouraging the adoption of efficient and effective alternatives to conventional antibiotics and promoting their use as replacements. Titanium dioxide nanoparticles (TiO2 NPs) have been reported to exhibit antibacterial properties. In this study, we synthesized and characterized TiO2 NPs in anatase and rutile forms with surface modification by geraniol (GER). RESULTS: The crystallinity and morphology of modified TiO2 NPs were analyzed by UV/Vis spectrophotometry, X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) with elemental mapping (EDS). The antimicrobial activity of TiO2 NPs with geraniol was assessed against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli. The minimum inhibitory concentration (MIC) values of modified NPs ranged from 0.25 to 1.0 mg/ml against all bacterial strains, and the live dead assay and fractional inhibitory concentration (FIC) supported the antibacterial properties of TiO2 NPs with GER. Moreover, TiO2 NPs with GER also showed a significant decrease in the biofilm thickness of MRSA. CONCLUSIONS: Our results suggest that TiO2 NPs with GER offer a promising alternative to antibiotics, particularly for controlling antibiotic-resistant strains. The surface modification of TiO2 NPs by geraniol resulted in enhanced antibacterial properties against multiple bacterial strains, including antibiotic-resistant MRSA. The potential applications of modified TiO2 NPs in the biomedical and environmental fields warrant further investigation.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Antibacterianos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana
2.
BMC Microbiol ; 23(1): 288, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803300

RESUMO

OBJECTIVES: Resistance to antibiotics among bacteria of clinical importance, including Staphylococcus aureus, is a serious problem worldwide and the search for alternatives is needed. Some metal complexes have antibacterial properties and when combined with antibiotics, they may increase bacterial sensitivity to antimicrobials. In this study, we synthesized the iron complex and tested it in combination with ampicillin (Fe16 + AMP) against S. aureus. METHODS: An iron complex (Fe16) was synthesized and characterized using spectroscopy methods. Confirmation of the synergistic effect between the iron complex (Fe16) and ampicillin (AMP) was performed using ζ-potential, infrared spectra and FICI index calculated from the minimum inhibitory concentration (MIC) from the checkerboard assay. Cytotoxic properties of combination Fe16 + AMP was evaluated on eukaryotic cell line. Impact of combination Fe16 + AMP on chosen genes of S. aureus were performed by Quantitative Real-Time PCR. RESULTS: The MIC of Fe16 + AMP was significantly lower than that of AMP and Fe16 alone. Furthermore, the infrared spectroscopy revealed the change in the ζ-potential of Fe16 + AMP. We demonstrated the ability of Fe16 + AMP to disrupt the bacterial membrane of S. aureus and that likely allowed for better absorption of AMP. In addition, the change in gene expression of bacterial efflux pumps at the sub-inhibitory concentration of AMP suggests an insufficient import of iron into the bacterial cell. At the same time, Fe16 + AMP did not have any cytotoxic effects on keratinocytes. CONCLUSIONS: Combined Fe16 + AMP therapy demonstrated significant synergistic and antimicrobial effects against S. aureus. This study supports the potential of combination therapy and further research.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Ampicilina/farmacologia , Sinergismo Farmacológico , Antibacterianos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana
3.
Environ Microbiol ; 24(12): 5788-5808, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36054322

RESUMO

Psyllids are phloem-feeding insects that can transmit plant pathogens such as phytoplasmas, intracellular bacteria causing numerous plant diseases worldwide. Their microbiomes are essential for insect physiology and may also influence the capacity of vectors to transmit pathogens. Using 16S rRNA gene metabarcoding, we compared the microbiomes of three sympatric psyllid species associated with pear trees in Central Europe. All three species are able to transmit 'Candidatus Phytoplasma pyri', albeit with different efficiencies. Our results revealed potential relationships between insect biology and microbiome composition that varied during psyllid ontogeny and between generations in Cacopsylla pyri and C. pyricola, as well as between localities in C. pyri. In contrast, no variations related to psyllid life cycle and geography were detected in C. pyrisuga. In addition to the primary endosymbiont Carsonella ruddii, we detected another highly abundant endosymbiont (unclassified Enterobacteriaceae). C. pyri and C. pyricola shared the same taxon of Enterobacteriaceae which is related to endosymbionts harboured by other psyllid species from various families. In contrast, C. pyrisuga carried a different Enterobacteriaceae taxon related to the genus Sodalis. Our study provides new insights into host-symbiont interactions in psyllids and highlights the importance of host biology and geography in shaping microbiome structure.


Assuntos
Hemípteros , Microbiota , Pyrus , Humanos , Animais , Hemípteros/microbiologia , RNA Ribossômico 16S/genética , Simbiose , Enterobacteriaceae/genética , Insetos , Microbiota/genética
4.
Microb Ecol ; 82(3): 602-612, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33547531

RESUMO

Anaplasma phagocytophilum is an important tick-borne zoonotic agent of human granulocytic anaplasmosis (HGA). In Europe, the Ixodes ticks are the main vector responsible for A. phagocytophilum transmission. A wide range of wild animals is involved in the circulation of this pathogen in the environment. Changes in populations of vertebrates living in different ecosystems impact the ecology of ticks and the epidemiology of tick-borne diseases. In this study, we investigated four species, Western European hedgehog (Erinaceus europaeus), northern white-breasted hedgehog (Erinaceus roumanicus), Eurasian red squirrel (Sciurus vulgaris), and the common blackbird (Turdus merula), to describe their role in the circulation of A. phagocytophilum in urban and periurban ecosystems. Ten different tissues were collected from cadavers of the four species, and blood and ear/skin samples from live blackbirds and hedgehogs. Using qPCR, we detected a high rate of A. phagocytophilum: Western European hedgehogs (96.4%), northern white-breasted hedgehogs (92.9%), Eurasian red squirrels (60%), and common blackbirds (33.8%). In the groEL gene, we found nine genotypes belonging to three ecotypes; seven of the genotypes are associated with HGA symptoms. Our findings underline the role of peridomestic animals in the ecology of A. phagocytophilum and indicate that cadavers are an important source of material for monitoring zoonotic pathogens. Concerning the high prevalence rate, all investigated species play an important role in the circulation of A. phagocytophilum in municipal areas; however, hedgehogs present the greatest anaplasmosis risk for humans. Common blackbirds and squirrels carry different A. phagocytophilum variants some of which are responsible for HGA.


Assuntos
Anaplasma phagocytophilum , Ixodes , Doenças Transmitidas por Carrapatos , Anaplasma phagocytophilum/genética , Animais , Ecossistema , Ouriços , Humanos
5.
Foodborne Pathog Dis ; 18(1): 49-55, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32762548

RESUMO

Salmonella enterica serovar Typhimurium is a pathogen harbored by livestock and shed in their feces, which serves as an acquisition source for adult house flies. This study used a green fluorescent protein (GFP) expressing strain of Salmonella Typhimurium to assess its acquisition by and survival within house flies, and transmission from and between flies in the presence or absence of cantaloupe. Female house flies were exposed to manure inoculated with either sterile phosphate-buffered saline or GFP-Salmonella Typhimurium for 12 h, then used in four experiments each performed over 24 h. Experiment 1 assessed the survival of GFP-Salmonella Typhimurium within inoculated flies. Experiment 2 determined transmission of GFP-Salmonella Typhimurium from inoculated flies to cantaloupe. Experiment 3 assessed fly acquisition of GFP-Salmonella Typhimurium from inoculated cantaloupe. Experiment 4 evaluated transmission of GFP-Salmonella Typhimurium between inoculated flies and uninoculated flies in the presence and absence of cantaloupe. GFP-Salmonella Typhimurium survived in inoculated flies but bacterial abundance decreased between 0 and 6 h without cantaloupe present and between 0 and 6 h and 6 and 24 h with cantaloupe present. Uninoculated flies acquired GFP-Salmonella Typhimurium from inoculated cantaloupe and bacterial abundance increased in cantaloupe and flies from 6 to 24 h. More uninoculated flies exposed to inoculated flies acquired GFP-Salmonella Typhimurium when cantaloupe was present than when absent. We infer that the presence of a shared food source facilitated the transfer of GFP-Salmonella Typhimurium from inoculated to uninoculated flies. Our study demonstrated that house flies acquired, harbored, and excreted viable GFP-Salmonella Typhimurium and transferred bacteria to food and each other. Understanding the dynamics of bacterial acquisition and transmission of bacteria between flies and food helps in assessing the risk flies pose to food safety and human health.


Assuntos
Cucumis melo/microbiologia , Moscas Domésticas/microbiologia , Salmonella typhimurium/patogenicidade , Animais , Feminino , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Proteínas de Fluorescência Verde/metabolismo
6.
Int J Syst Evol Microbiol ; 70(12): 6482-6490, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33125314

RESUMO

Strain CS-1T, a novel facultative anaerobic bacterium, was isolated from the larval gastrointestinal tract of the biting midge, Culicoides sonorensis, a vector of the epizootic haemorrhagic disease virus and the bluetongue virus. Cells were Gram-stain-positive, non-motile, non-spore-forming, pleomorphic rods. Optimal growth occurred at pH 7.5 and 37 °C. The G+C content of the genomic DNA was 38.3 mol%, estimated by using HPLC. The dominant cellular fatty acids were C14 : 0 (45.9 %) and C16 : 0 (26.6 %). The polar lipid profile comprised glycolipids, diphosphatidylglycerol, phospholipids and phosphoglycolipids. Respiratory quinones were not detected. Strain CS-1T had very low 16S rRNA gene similarity to members of the phylum Firmicutes: Macrococcus canis KM45013T (85 % similarity) and Turicibacter sanguinis MOL361T (88 % similarity). Phylogenetic analysis based on 16S rRNA, rpoB, gyrB genes, and conserved protein sequences of the whole genome revealed that strain CS-1T was related to members of the classes Bacilli and Erysipelotrichia within the phylum Firmicutes. Furthermore, average nucleotide identity and digital DNA-DNA hybridization analyses of the whole genome revealed very low sequence similarity to species of Bacilli and Erysipelotrichaceae (Macrococcus canis KM45013T and Turicibacter sp. H121). These results indicate that strain CS-1T belongs to the phylum Firmicutes and represents a new species of a novel genus, family, order and class. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic characteristics, we propose the novel taxon Culicoidibacter larvae gen. nov., sp. nov. with the type strain CS-1T (=CCUG 71726T=DSM 106607T) within the hereby new proposed novel family Culicoidibacteraceae fam. nov., new order Culicoidibacaterales ord. nov. and new class Culicoidibacteria classis nov. in the phylum Firmicutes.


Assuntos
Ceratopogonidae/microbiologia , Firmicutes/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Firmicutes/genética , Trato Gastrointestinal/microbiologia , Larva/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
7.
Microb Ecol ; 77(4): 1091, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30915517

RESUMO

The original published version of this article had mistakes in figure legends. Correct figure legends are presented below.

8.
Microb Ecol ; 77(4): 1082-1090, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30806729

RESUMO

The digestive tract of medicinal leeches from commercial suppliers has been investigated previously and comprises of a relatively simple bacterial community. However, the microbiome of medicinal leeches collected directly from the natural habitat has not been examined. In this study, we characterized the bacterial community in the digestive tract (anterior crop, posterior crop, and intestine) of the European medicinal leech, Hirudo verbana, collected from the Danube river using culture-independent and culture-dependent approaches. Culture-independent approach confirmed that the digestive tract of H. verbana carries a relatively simple bacterial community with species richness in the individual samples ranging from 43 to164. The dominant bacterial taxon was Mucinivorans sp. (49.7% of total reads), followed by Aeromonas sp. (18.7% of total reads). Several low abundance taxa, new for H. verbana, such as Phreatobacter, Taibaiella, Fluviicola, Aquabacterium, Burkholderia, Hydrogenophaga, Wolinella, and unidentified Chitinophagia, were also detected. The aerobic culturing approach showed Aeromonas veronii (Proteobacteria), the known leech symbiont, as the most dominant taxon followed by several Pseudomonas and Acidovorax spp. No significant differences in the bacterial community composition were detected among different parts of the digestive tract of individual leeches. However, the overall composition of the bacterial community among individual specimen varied significantly and this is possibly due to differences in leech age, feeding status, and blood source. Our results showed that the core bacterial community of H. verbana collected from the natural habitat is similar to that reported from the digestive tract of commercially supplied leeches maintained in the laboratory.


Assuntos
Bactérias/classificação , Microbioma Gastrointestinal , Sanguessugas/microbiologia , Animais , Bactérias/genética , Trato Gastrointestinal/microbiologia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Rios , Romênia
9.
Cell Microbiol ; 19(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28580630

RESUMO

For many arthropod vectors, the diverse bacteria and fungi that inhabit the gut can negatively impact pathogen colonization. Our attempts to exploit antibiotic treatment of colonized Phlebotomus duboscqi sand flies in order to improve their vector competency for Leishmania major resulted instead in flies that were refractory to the development of transmissible infections due to the inability of the parasite to survive and to colonize the anterior midgut with infective, metacyclic stage promastigotes. The parasite survival and development defect could be overcome by feeding the flies on different symbiont bacteria but not by feeding them on bacterial supernatants or replete medium. The inhibitory effect of the dysbiosis was moderated by lowering the concentration of sucrose (<30% w/v) used in the sugar feeds to maintain the colony. Exposure of promastigotes to 30% sucrose was lethal to the parasite in vitro. Confocal imaging revealed that the killing in vivo was confined to promastigotes that had migrated to the anterior plug region, corresponding to the highest concentrations of sucrose. The data suggest that sucrose utilization by the microbiota is essential to promote the appropriate osmotic conditions required for the survival of infective stage promastigotes in vivo.


Assuntos
Leishmania major/fisiologia , Microbiota/fisiologia , Phlebotomus/microbiologia , Phlebotomus/parasitologia , Psychodidae/microbiologia , Psychodidae/parasitologia , Animais , Insetos Vetores/microbiologia , Leishmania major/efeitos dos fármacos , Pressão Osmótica/efeitos dos fármacos , Pressão Osmótica/fisiologia , Sacarose/farmacologia
10.
Proc Natl Acad Sci U S A ; 112(51): 15678-83, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26644557

RESUMO

Aggregation of the German cockroach, Blattella germanica, is regulated by fecal aggregation agents (pheromones), including volatile carboxylic acids (VCAs). We demonstrate that the gut microbial community contributes to production of these semiochemicals. Chemical analysis of the fecal extract of B. germanica revealed 40 VCAs. Feces from axenic cockroaches (no microorganisms in the alimentary tract) lacked 12 major fecal VCAs, and 24 of the remaining compounds were represented at extremely low amounts. Olfactory and aggregation bioassays demonstrated that nymphs strongly preferred the extract of control feces over the fecal extract of axenic cockroaches. Additionally, nymphs preferred a synthetic blend of 6 fecal VCAs over a solvent control or a previously identified VCA blend. To test whether gut bacteria contribute to the production of fecal aggregation agents, fecal aerobic bacteria were cultured, isolated, and identified. Inoculation of axenic cockroaches with individual bacterial taxa significantly rescued the aggregation response to the fecal extract, and inoculation with a mix of six bacterial isolates was more effective than with single isolates. The results indicate that the commensal gut microbiota contributes to production of VCAs that act as fecal aggregation agents and that cockroaches discriminate among the complex odors that emanate from a diverse microbial community. Our results highlight the pivotal role of gut bacteria in mediating insect-insect communication. Moreover, because the gut microbial community reflects the local environment, local plasticity in fecal aggregation pheromones enables colony-specific odors and fidelity to persistent aggregation sites.


Assuntos
Blattellidae/fisiologia , Trato Gastrointestinal/microbiologia , Feromônios/fisiologia , Animais , Comunicação , Fezes/microbiologia
11.
Environ Microbiol ; 19(5): 2025-2036, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28276133

RESUMO

American crow (Corvus brachyrhynchos) faeces were tested for Escherichia coli with plasmid-mediated quinolone resistance (PMQR), extended-spectrum beta-lactamases (ESBL) and AmpC beta-lactamases. A total of 590 faecal samples were collected at four roosting sites in the USA and cultivated on selective media. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were performed to assess clonality. Transferability of resistance genes was studied using conjugation and transformation bioassays. In total, 78 (13%, n = 590) cefotaxime-resistant isolates were obtained, of which 66 and 12 displayed AmpC and ESBL phenotypes, respectively. Fifty-four AmpC-producing isolates carried blaCMY-2 . Isolates producing ESBLs contained genes blaCTX-M-27 (5 isolates), blaCTX-M-15 (4), blaCTX-M-14 (2) and blaCTX-M-1 (1). Ninety isolates (15%, n = 590) with reduced susceptibility to ciprofloxacin were obtained, among which 14 harboured PMQR genes aac(6')-Ib-cr (4 isolates), qnrB19 (3), qnrS1 (2), qnrA1 (2), qnrB2 (1), qnrB6 (1) and qnrD3 (1). High genetic diversity was revealed by PFGE and MLST. Epidemiologically important E. coli clones (e.g., ST131, ST405) were identified. Plasmids carrying blaCMY-2 were assigned predominantly to IncA/C (8 plasmids), IncI1/ST23 (5) and IncI1/ST12 (3). The study demonstrates a widespread occurrence of E. coli with ESBL, AmpC and PMQR genes associated with clinically important multidrug-resistant clones and epidemic plasmids, in American crows.


Assuntos
Proteínas de Bactérias/genética , Cefotaxima/farmacologia , Ciprofloxacina/farmacologia , Corvos/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , beta-Lactamases/genética , Animais , Antibacterianos , Doenças das Aves/microbiologia , Eletroforese em Gel de Campo Pulsado , Infecções por Escherichia coli , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Plasmídeos/genética , Estados Unidos
12.
Foodborne Pathog Dis ; 13(2): 65-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26650821

RESUMO

BACKGROUND AND OBJECTIVE: Stable flies (Stomoxys calcitrans L.) are very common around confined and pastured cattle, and due to their painful bites they are very important animal pests. Cattle are asymptomatic reservoirs of foodborne pathogens, Escherichia coli O157:H7 and other Shiga-toxigenic E. coli serotypes (STEC). In the present study, the potential of stable flies to carry STEC in a beef cattle feedlot was assessed. METHODS: Stable flies (n = 180) were collected over 3 summer months and processed individually for STEC-8 that included the serotype O157 and seven non-O157 serotypes (O26, O45, O103, O104, O111, O121, and O145). Isolation and detection of STEC was based on direct plating as well as the enrichment/immunomagnetic separation approach. Modified Posse agar (mP) was used for culturing non-O157 serotypes and sorbitol MacConkey agar with cefixime and potassium tellurite (CT-SMAC) for E. coli O157. Multiplex polymerase chain reactions were used for differentiation of individual serotypes and detection of virulence genes (stx1, stx2, eae, and ehxA). RESULTS AND CONCLUSIONS: Of 180 stable flies, 67 (37.2%) carried enterics on mP (mean: 3.6 ± 1.05 × 10(6) colony-forming units [CFU]/fly) and 55/180 (30.5%) were positive for bacteria on CT-SMAC (mean: 1.2 ± 1.08 × 10(4) CFU/fly). However, stable flies positive for E. coli serotypes of interest were very rare (prevalence: 1.1%). The three serotype-positive isolates, two E. coli O26 and one E. coli O45, were recovered from two flies and neither of them harbored the virulence genes. We conclude that stable flies likely do not play a role as a biological vector and/or reservoir of STEC-8 in cattle feedlots.


Assuntos
Bovinos/microbiologia , Trato Gastrointestinal/microbiologia , Muscidae/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Adesinas Bacterianas/análise , Ágar , Animais , Técnicas de Cultura de Células , Meios de Cultura , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Proteínas de Escherichia coli/análise , Proteínas Hemolisinas/análise , Separação Imunomagnética , Reação em Cadeia da Polimerase Multiplex , Sorogrupo , Toxina Shiga I/análise , Toxina Shiga II/análise , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Fatores de Virulência/genética
13.
Antonie Van Leeuwenhoek ; 107(5): 1281-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25772302

RESUMO

Coraciiform birds hoopoe (Upupa epops), common kingfisher (Alcedo atthis) and European roller (Coracius garrulus) were examined for enterococci in their cloacae and uropygial glands. The enterococcal isolates were identified at the species level using several genomic and proteomic methods, screened for antibiotic susceptibility and genotyped by pulsed-field gel electrophoresis (PFGE). Clonality of isolates from the common kingfisher was also assessed by multi-locus sequence typing (MLST). Using selective media, putative enterococcal isolates (n = 117) were recovered from 74% (32 out of a total of 43) of the bird samples and 114 isolates were confirmed as enterococci. Overall, among the total of 6 different species detected, Enterococcus faecalis was dominant (59%) in all three bird species. The second most frequently isolated species was Enterococcus casseliflavus (32%). PFGE revealed great diversity of strains from different bird species and anatomic location. Closely related strains were found only from nestlings from the same nest. No genes conferring resistance to vancomycin (vanA, vanB, vanC1 and van C2/C3) or erythromycin (erm A, ermB and mefA/E) were detected. MLST analysis and eBURST clustering revealed that sequence types of E. faecalis from the common kingfisher were identical to those of isolates found previously in water, chickens, and humans.


Assuntos
Biodiversidade , Aves/microbiologia , Enterococcus/isolamento & purificação , Animais , Antibacterianos/farmacologia , Eletroforese em Gel de Campo Pulsado , Enterococcus/classificação , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , Prevalência
14.
Environ Microbiol ; 16(4): 939-49, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23919480

RESUMO

We studied the vanA-carrying vancomycin-resistant enterococci (VRE) isolated from American crows in the United States during the winter 2011/2012. Faecal samples from crows were cultured selectively for VRE and characterized. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to examine epidemiological relationships of vanA-containing VRE. Isolates were tested in vitro for their ability to horizontally transfer the vancomycin resistance trait. VRE with the vanA gene were found in 15 (2.5%) of 590 crows samples, from which we obtained 22 different isolates. Enterococcal species were Enterococcus faecium (14) and E. faecalis (8). One, two and 19 isolates originated from Kansas, New York State and Massachusetts, respectively. Based on MLST analysis, E. faecium isolates were grouped as ST18 (6 isolates), ST555 (2), and novel types ST749 (1), ST750 (3), ST751 (1), ST752 (1). Enterococcus faecalis isolates belonged to ST6 (1), ST16 (3) and ST179 (4). All isolates were able to transfer the vancomycin resistance trait via filter mating with very high transfer range. Clinically important enterococci with the vanA gene occur in faeces of wild American crows throughout the United States. These migrating birds may contribute to the dissemination of VRE in environment over large distances. [Correction added after first online publication on 06 August 2013: The number of E. faecium ST752 isolate is now amended to '1', consistent with that shown in the 'Results' section and Figure 2.].


Assuntos
Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Corvos/microbiologia , Enterococcus faecalis/genética , Enterococcus faecium/genética , Resistência a Vancomicina/genética , Animais , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/isolamento & purificação , Fezes/microbiologia , Transferência Genética Horizontal , Tipagem de Sequências Multilocus , Estados Unidos
15.
Appl Environ Microbiol ; 80(12): 3562-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24705326

RESUMO

Antibiotic-resistant bacterial infections result in higher patient mortality rates, prolonged hospitalizations, and increased health care costs. Extensive use of antibiotics as growth promoters in the animal industry represents great pressure for evolution and selection of antibiotic-resistant bacteria on farms. Despite growing evidence showing that antibiotic use and bacterial resistance in food animals correlate with resistance in human pathogens, the proof for direct transmission of antibiotic resistance is difficult to provide. In this review, we make a case that insects commonly associated with food animals likely represent a direct and important link between animal farms and urban communities for antibiotic resistance traits. Houseflies and cockroaches have been shown to carry multidrug-resistant clonal lineages of bacteria identical to those found in animal manure. Furthermore, several studies have demonstrated proliferation of bacteria and horizontal transfer of resistance genes in the insect digestive tract as well as transmission of resistant bacteria by insects to new substrates. We propose that insect management should be an integral part of pre- and postharvest food safety strategies to minimize spread of zoonotic pathogens and antibiotic resistance traits from animal farms. Furthermore, the insect link between the agricultural and urban environment presents an additional argument for adopting prudent use of antibiotics in the food animal industry.


Assuntos
Bactérias/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Infecções Bacterianas/veterinária , Farmacorresistência Bacteriana , Insetos/microbiologia , Gado/microbiologia , Animais , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Bacterianas/transmissão , Ecossistema , Humanos , Zoonoses/microbiologia , Zoonoses/transmissão
16.
J Med Entomol ; 51(1): 63-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24605454

RESUMO

House flies are among the most important nonbiting insect pests of medical and veterinary importance. Larvae develop in decaying organic substrates and their survival strictly depends on an active microbial community. House flies have been implicated in the ecology and transmission of enterococci, including multi-antibiotic-resistant and virulent strains of Enterococcus faecalis. In this study, eight American Type Culture Collection type strains of enterococci including Enterococcus avium, Enterococcus casseliflavus, Enterococcus durans, Enterococcus hirae, Enterococcus mundtii, Enterococcus gallinarum, Enterococcusfaecalis, and Enterococcusfaecium were evaluated for their significance in the development of house flies from eggs to adults in bacterial feeding assays. Furthermore, the bacterial colonization of the gut of teneral flies as well as the importance of several virulence traits of E. faecalis in larval mortality was assessed. Overall survival of house flies (egg to adult) was significantly higher when grown with typically nonpathogenic enterococcal species such as E. hirae (76.0% survival), E. durans (64.0%), and E. avium (64.0%) compared with that with clinically important species E. faecalis (24.0%) and E. faecium (36.0%). However, no significant differences in survival of house fly larvae were detected when grown with E. faecalis strains carrying various virulence traits, including isogenic mutants of the human clinical isolate E. faecalis V583 with in-frame deletions of gelatinase, serine protease, and capsular polysaccharide serotype C. Enterococci were commonly detected in fly puparia (range: 75-100%; concentration: 103-105 CFU/puparium);however, the prevalence of enterococci in teneral flies varied greatly: from 25.0 (E. casseliflavus) to 89.5% (E. hirae). In conclusion, depending on the species, enterococci variably support house fly larval development and colonize the gut of teneral adults. The human pathogenic species, E. faecalis and E. faecium, poorly support larval development and are likely acquired in nature by adult flies during feeding. House fly larvae do not appear to be a suitable model organism for assessment of enterococcal virulence traits.


Assuntos
Enterococcus/fisiologia , Moscas Domésticas/microbiologia , Animais , Enterococcus/patogenicidade , Moscas Domésticas/crescimento & desenvolvimento , Humanos , Larva/crescimento & desenvolvimento , Larva/microbiologia
17.
Vet Parasitol Reg Stud Reports ; 50: 101007, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38644036

RESUMO

The brown dog tick, Rhipicephalus sanguineus is a complex of tick species with an unsettled species concept. In Europe, R. sanguineus is considered mainly a Mediterranean tick with sporadic findings in central and northern Europe. R. sanguineus is known as a vector of a range of pathogens of medical and veterinary importance, most of which not yet reported as autochthonous in Hungary. A total of 1839 ticks collected by veterinarians from dogs and cats were obtained in Hungary. The study aims at precise determination of ticks identified as R. sanguineus and detection of pathogens in collected ticks. All ticks were morphologically determined and 169 individuals were identified as R. sanguineus. A subset of 15 ticks was selected for molecular analysis (16S rDNA, 12S rDNA, COI). Phylogenetic analyses invariably placed sequences of all three markers into a single haplotype identified as R. sanguineus sensu stricto. All 169 brown dog ticks were tested for the presence of A. platys, E. canis, R. conorii, B. vogeli and H. canis. None of the investigated ticks was positive for the screened pathogens, though A. phagocytophilum sequence was detected in a single tick.


Assuntos
Anaplasma , Doenças do Cão , Filogenia , RNA Ribossômico , Rhipicephalus sanguineus , Infestações por Carrapato , Animais , Cães , Hungria , Rhipicephalus sanguineus/microbiologia , Doenças do Cão/parasitologia , Doenças do Cão/diagnóstico , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Feminino , Masculino , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Rickettsia conorii/isolamento & purificação , Rickettsia conorii/genética , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Gatos/parasitologia , Ehrlichia canis/isolamento & purificação , Ehrlichia canis/genética
18.
Parasit Vectors ; 17(1): 196, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685096

RESUMO

BACKGROUND: Ixodes inopinatus was described from Spain on the basis of morphology and partial sequencing of 16S ribosomal DNA. However, several studies suggested that morphological differences between I. inopinatus and Ixodes ricinus are minimal and that 16S rDNA lacks the power to distinguish the two species. Furthermore, nuclear and mitochondrial markers indicated evidence of hybridization between I. inopinatus and I. ricinus. In this study, we tested our hypothesis on tick dispersal from North Africa to Southern Europe and determined the prevalence of selected tick-borne pathogens (TBPs) in I. inopinatus, I. ricinus, and their hybrids. METHODS: Ticks were collected in Italy and Algeria by flagging, identified by sequencing of partial TROSPA and COI genes, and screened for Borrelia burgdorferi s.l., B. miyamotoi, Rickettsia spp., and Anaplasma phagocytophilum by polymerase chain reaction and sequencing of specific markers. RESULTS: Out of the 380 ticks, in Italy, 92 were I. ricinus, 3 were I. inopinatus, and 136 were hybrids of the two species. All 149 ticks from Algeria were I. inopinatus. Overall, 60% of ticks were positive for at least one TBP. Borrelia burgdorferi s.l. was detected in 19.5% of ticks, and it was significantly more prevalent in Ixodes ticks from Algeria than in ticks from Italy. Prevalence of Rickettsia spotted fever group (SFG) was 51.1%, with significantly greater prevalence in ticks from Algeria than in ticks from Italy. Borrelia miyamotoi and A. phagocytophilum were detected in low prevalence (0.9% and 5.2%, respectively) and only in ticks from Italy. CONCLUSIONS: This study indicates that I. inopinatus is a dominant species in Algeria, while I. ricinus and hybrids were common in Italy. The higher prevalence of B. burgdorferi s.l. and Rickettsia SFG in I. inopinatus compared with that in I. ricinus might be due to geographical and ecological differences between these two tick species. The role of I. inopinatus in the epidemiology of TBPs needs further investigation in the Mediterranean Basin.


Assuntos
Ixodes , Rickettsia , Animais , Ixodes/microbiologia , Itália/epidemiologia , Argélia/epidemiologia , Rickettsia/isolamento & purificação , Rickettsia/genética , Rickettsia/classificação , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Prevalência , Borrelia/genética , Borrelia/isolamento & purificação , Borrelia/classificação , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Anaplasma phagocytophilum/classificação , Feminino , Hibridização Genética , Masculino , RNA Ribossômico 16S/genética , Borrelia burgdorferi/genética , Borrelia burgdorferi/isolamento & purificação , Borrelia burgdorferi/classificação
19.
Environ Microbiol ; 15(2): 548-56, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23116146

RESUMO

This study's aims were to assess the prevalence of, and to characterize, vancomycin-resistant enterococci (VRE) from rooks (Corvus frugilegus) wintering in Europe during 2010/2011. Faeces samples were cultivated selectively for VRE and characterized. Pulsed-field gel electrophoresis and multilocus sequence typing (MLST) were used to examine epidemiologic relationships of vanA-containing VRE. The vanA-carrying VRE were tested in vitro for mobility of vancomycin resistance traits. VRE were found in 62 (6%) of 1073 rook samples. Enterococcal species diversity comprised Enterococcus gallinarum (48 isolates), followed by E. faecium (9) and E. faecalis (5). Eight VRE harboured the vanA and ermB genes. Seven vanA-carrying VRE originated from the Czech Republic and one from Germany. All vanA-carrying VRE were identified as E. faecium. Based on MLST analysis, six vanA-positive isolates were grouped as ST92 type, one isolate belonged to ST121, and the remaining one was described as a novel type ST671. Seven out of eight isolates were able to transfer the vancomycin resistance trait via filter mating with a transfer rate of 8.95 ± 3.25 × 10(-7) transconjugants per donor. In conclusion, wintering rooks in some European countries may disseminate clinically important enterococci and pose a risk for environmental contamination.


Assuntos
Antibacterianos/farmacologia , Corvos/microbiologia , Reservatórios de Doenças/microbiologia , Enterococcus/efeitos dos fármacos , Enterococcus/fisiologia , Resistência a Vancomicina , Vancomicina/farmacologia , Animais , Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Análise por Conglomerados , Corvos/genética , Eletroforese em Gel de Campo Pulsado , Enterococcus/genética , Enterococcus/isolamento & purificação , Europa (Continente) , Fezes/microbiologia , Transferência Genética Horizontal/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Resistência a Vancomicina/genética
20.
J Clin Microbiol ; 51(11): 3567-78, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23966487

RESUMO

Approximately 15% of foster kittens die before 8 weeks of age, with most of these kittens demonstrating clinical signs or postmortem evidence of enteritis. While a specific cause of enteritis is not determined in most cases, these kittens are often empirically administered probiotics that contain enterococci. The enterococci are members of the commensal intestinal microbiota but also can function as opportunistic pathogens. Given the complicated role of enterococci in health and disease, it would be valuable to better understand what constitutes a "healthy" enterococcal community in these kittens and how this microbiota is impacted by severe illness. In this study, we characterized the ileum mucosa-associated enterococcal community of 50 apparently healthy and 50 terminally ill foster kittens. In healthy kittens, Enterococcus hirae was the most common species of ileum mucosa-associated enterococci and was often observed to adhere extensively to the small intestinal epithelium. These E. hirae isolates generally lacked virulence traits. In contrast, non-E. hirae enterococci, notably Enterococcus faecalis, were more commonly isolated from the ileum mucosa of kittens with terminal illness. Isolates of E. faecalis had numerous virulence traits and multiple antimicrobial resistances. Moreover, the attachment of Escherichia coli to the intestinal epithelium was significantly associated with terminal illness and was not observed in any kitten with adherent E. hirae. These findings identify a significant difference in the species of enterococci cultured from the ileum mucosa of kittens with terminal illness compared to the species cultured from healthy kittens. In contrast to prior case studies that associated enteroadherent E. hirae with diarrhea in young animals, these controlled studies identified E. hirae as more often isolated from healthy kittens and adherence of E. hirae as more common and extensive in healthy kittens than in sick kittens.


Assuntos
Biota , Doenças do Gato/microbiologia , Enterite/veterinária , Enterococcus/isolamento & purificação , Escherichia coli/isolamento & purificação , Íleo/microbiologia , Mucosa Intestinal/microbiologia , Animais , Animais Recém-Nascidos , Biofilmes/crescimento & desenvolvimento , Doenças do Gato/mortalidade , Gatos , Enterite/microbiologia , Enterite/mortalidade , Enterococcus/fisiologia , Escherichia coli/fisiologia
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