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Alina Wieliczko - One of the best experts on this subject based on the ideXlab platform.
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Prevalence of Chlamydia psittaci and Other Chlamydia Species in Wild Birds in Poland.
Vector-borne and Zoonotic Diseases, 2015Co-Authors: Marta Krawiec, Tomasz Piasecki, Alina WieliczkoAbstract:Abstract Avian chlamydiosis is a zoonotic disease occurring in humans, poultry, and exotic birds. It has been suggested that some wild bird species play an important role as reservoirs for Chlamydia, especially Chlamydia psittaci. Whereas C. psittaci is the predominant Chlamydial agent in birds, in the present study we have determined the prevalence of different species of Chlamydia among selected wild bird species in Poland using a rapid and sensitive real-time PCR method. In total, 369 free-living birds from 35 bird species and 15 orders were examined. Samples from 27 birds (7.3%) were positive for Chlamydial DNA in the PCR; 22 positive samples (81.5%) belonged to C. psittaci, three to Chlamydia trachomatis (11.1%), and two (7.4%) classified only to the genus Chlamydia. Most of C. psittaci–positive samples belonged to five orders: Anseriformes, Columbiformes, Gruiformes, Phasianiformes, and Passeriformes. All C. trachomatis samples were obtained from Eurasian coots (Gruiformes). Two Chlamydia-positive s...
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Prevalence of Chlamydia psittaci and Other Chlamydia Species in Wild Birds in Poland.
Vector-Borne and Zoonotic Diseases, 2015Co-Authors: Marta Krawiec, Tomasz Piasecki, Alina WieliczkoAbstract:Avian chlamydiosis is a zoonotic disease occurring in humans, poultry, and exotic birds. It has been suggested that some wild bird species play an important role as reservoirs for Chlamydia, especially Chlamydia psittaci. Whereas C. psittaci is the predominant Chlamydial agent in birds, in the present study we have determined the prevalence of different species of Chlamydia among selected wild bird species in Poland using a rapid and sensitive real-time PCR method. In total, 369 free-living birds from 35 bird species and 15 orders were examined. Samples from 27 birds (7.3%) were positive for Chlamydial DNA in the PCR; 22 positive samples (81.5%) belonged to C. psittaci, three to Chlamydia trachomatis (11.1%), and two (7.4%) classified only to the genus Chlamydia. Most of C. psittaci-positive samples belonged to five orders: Anseriformes, Columbiformes, Gruiformes, Phasianiformes, and Passeriformes. All C. trachomatis samples were obtained from Eurasian coots (Gruiformes). Two Chlamydia-positive samples not classified to any Chlamydia species were obtained from a common wood pigeon (Columbiformes) and a common buzzard (Accipitriformes). Detection of C. psittaci and C. trachomatis in free-living bird populations force to think on significance of birds as reservoir of varied Chlamydia species and their epidemiological importance.
Nicole Borel - One of the best experts on this subject based on the ideXlab platform.
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Novel Chlamydia species isolated from snakes are temperature-sensitive and exhibit decreased susceptibility to azithromycin
Scientific Reports, 2018Co-Authors: Eveline Staub, Gilbert Greub, Manuela Donati, Hanna Marti, Roberta Biondi, Aurora Levi, Cory Ann Leonard, Trestan Pillonel, Helena M. B. Seth-smith, Nicole BorelAbstract:Chlamydia species have recently been recognized as emerging pathogens in snakes. However, isolation of novel snake Chlamydiae is critical and their growth characteristics are largely unknown. In this study, two novel Chlamydial species are described: Chlamydia serpentis and Chlamydia poikilothermis , isolated after attempts on 23 cloacal and choanal swabs from 18 PCR-positive captive snakes originating from different Swiss snake collections. Isolation success, growth curve and infectivity rates over a 48-hour time period were dependent on temperature (37 °C for C . serpentis , 28 °C for C . poikilothermis ). C . serpentis and C . poikilothermis were sensitive to tetracycline and moxifloxacin during evaluation by in vitro antibiotic susceptibility assay but intermediate to resistant (2–4 μg/ml) to azithromycin. Whole genome sequencing of the isolates provided proof of the novel species status, and gives insights into the evolution of these branches of genus Chlamydia .
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Culture-independent genomic characterisation of Candidatus Chlamydia sanzinia, a novel uncultivated bacterium infecting snakes
BMC Genomics, 2016Co-Authors: Alyce Taylor-brown, Nathan L. Bachmann, Nicole Borel, Adam PolkinghorneAbstract:Background Recent molecular studies have revealed considerably more diversity in the phylum Chlamydiae than was previously thought. Evidence is growing that many of these novel Chlamydiae may be important pathogens in humans and animals. A significant barrier to characterising these novel Chlamydiae is the requirement for culturing. We recently identified a range of novel uncultured Chlamydiae in captive snakes in Switzerland, however, nothing is known about their biology. Using a metagenomics approach, the aim of this study was to characterise the genome of a novel Chlamydial taxon from the choana of a captive snake. In doing so, we propose a new candidate species in the genus Chlamydia ( Candidatus Chlamydia sanzinia) and reveal new information about the biological diversity of this important group of pathogens. Results We identified two Chlamydial genomic contigs: a 1,113,073 bp contig, and a 7,504 bp contig, representing the chromosome and plasmid of Ca . Chlamydia sanzinia strain 2742-308, respectively. The 998 predicted coding regions include an expanded repertoire of outer membrane proteins (Pmps and Omps), some of which exhibited frameshift mutations, as well as several Chlamydial virulence factors such as the translocating actin-recruitment phosphoprotein (Tarp) and macrophage inhibition potentiator (Mip). A suite of putative inclusion membrane proteins were also predicted. Notably, no evidence of a traditional Chlamydial plasticity zone was identified. Phylogenetically, Ca . Chlamydia sanzinia forms a clade with C. pneumoniae and C. pecorum , distinct from former “ Chlamydophila ” species. Conclusions Genomic characterisation of a novel uncultured Chlamydiae from the first reptilian host has expanded our understanding of the diversity and biology of a genus that was thought to be the most well-characterised in this unique phylum. It is anticipated that this method will be suitable for characterisation of other novel Chlamydiae.
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culture independent genomic characterisation of candidatus Chlamydia sanzinia a novel uncultivated bacterium infecting snakes
BMC Genomics, 2016Co-Authors: Alyce Taylorbrown, Nathan L. Bachmann, Nicole Borel, Adam PolkinghorneAbstract:Background Recent molecular studies have revealed considerably more diversity in the phylum Chlamydiae than was previously thought. Evidence is growing that many of these novel Chlamydiae may be important pathogens in humans and animals. A significant barrier to characterising these novel Chlamydiae is the requirement for culturing. We recently identified a range of novel uncultured Chlamydiae in captive snakes in Switzerland, however, nothing is known about their biology. Using a metagenomics approach, the aim of this study was to characterise the genome of a novel Chlamydial taxon from the choana of a captive snake. In doing so, we propose a new candidate species in the genus Chlamydia (Candidatus Chlamydia sanzinia) and reveal new information about the biological diversity of this important group of pathogens.
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Chlamydial Antibiotic Resistance and Treatment Failure in Veterinary and Human Medicine
Current Clinical Microbiology Reports, 2016Co-Authors: Nicole Borel, Cory Leonard, Jessica Slade, Robert V. SchoborgAbstract:The Chlamydiaceae are widespread pathogens of both humans and animals. Chlamydia trachomatis infection causes blinding trachoma and reproductive complications in humans. Chlamydia pneumoniae causes human respiratory tract infections and atypical pneumonia. Chlamydia suis infection is associated with conjunctivitis, diarrhea, and failure to gain weight in domestic swine. Chlamydial infections in humans and domesticated animals are generally controlled by antibiotic treatment—particularly macrolides (usually azithromycin) and tetracyclines (tetracycline and doxycycline). Tetracycline-containing feed has also been used to limit infections and promote growth in livestock populations, although its use has decreased because of growing concerns about antimicrobial resistance development. Because Sandoz and Rockey published an elegant review of Chlamydial anti-microbial resistance in 2010, we will review the following: (i) antibiotic resistance in C. suis , (ii) recent evidence for acquired resistance in human Chlamydial infections, and (iii) recent non-genetic mechanisms of antibiotic resistance that may contribute to treatment failure.
Adam Polkinghorne - One of the best experts on this subject based on the ideXlab platform.
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Culture-independent genomic characterisation of Candidatus Chlamydia sanzinia, a novel uncultivated bacterium infecting snakes
BMC Genomics, 2016Co-Authors: Alyce Taylor-brown, Nathan L. Bachmann, Nicole Borel, Adam PolkinghorneAbstract:Background Recent molecular studies have revealed considerably more diversity in the phylum Chlamydiae than was previously thought. Evidence is growing that many of these novel Chlamydiae may be important pathogens in humans and animals. A significant barrier to characterising these novel Chlamydiae is the requirement for culturing. We recently identified a range of novel uncultured Chlamydiae in captive snakes in Switzerland, however, nothing is known about their biology. Using a metagenomics approach, the aim of this study was to characterise the genome of a novel Chlamydial taxon from the choana of a captive snake. In doing so, we propose a new candidate species in the genus Chlamydia ( Candidatus Chlamydia sanzinia) and reveal new information about the biological diversity of this important group of pathogens. Results We identified two Chlamydial genomic contigs: a 1,113,073 bp contig, and a 7,504 bp contig, representing the chromosome and plasmid of Ca . Chlamydia sanzinia strain 2742-308, respectively. The 998 predicted coding regions include an expanded repertoire of outer membrane proteins (Pmps and Omps), some of which exhibited frameshift mutations, as well as several Chlamydial virulence factors such as the translocating actin-recruitment phosphoprotein (Tarp) and macrophage inhibition potentiator (Mip). A suite of putative inclusion membrane proteins were also predicted. Notably, no evidence of a traditional Chlamydial plasticity zone was identified. Phylogenetically, Ca . Chlamydia sanzinia forms a clade with C. pneumoniae and C. pecorum , distinct from former “ Chlamydophila ” species. Conclusions Genomic characterisation of a novel uncultured Chlamydiae from the first reptilian host has expanded our understanding of the diversity and biology of a genus that was thought to be the most well-characterised in this unique phylum. It is anticipated that this method will be suitable for characterisation of other novel Chlamydiae.
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culture independent genomic characterisation of candidatus Chlamydia sanzinia a novel uncultivated bacterium infecting snakes
BMC Genomics, 2016Co-Authors: Alyce Taylorbrown, Nathan L. Bachmann, Nicole Borel, Adam PolkinghorneAbstract:Background Recent molecular studies have revealed considerably more diversity in the phylum Chlamydiae than was previously thought. Evidence is growing that many of these novel Chlamydiae may be important pathogens in humans and animals. A significant barrier to characterising these novel Chlamydiae is the requirement for culturing. We recently identified a range of novel uncultured Chlamydiae in captive snakes in Switzerland, however, nothing is known about their biology. Using a metagenomics approach, the aim of this study was to characterise the genome of a novel Chlamydial taxon from the choana of a captive snake. In doing so, we propose a new candidate species in the genus Chlamydia (Candidatus Chlamydia sanzinia) and reveal new information about the biological diversity of this important group of pathogens.
Marta Krawiec - One of the best experts on this subject based on the ideXlab platform.
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Prevalence of Chlamydia psittaci and Other Chlamydia Species in Wild Birds in Poland.
Vector-borne and Zoonotic Diseases, 2015Co-Authors: Marta Krawiec, Tomasz Piasecki, Alina WieliczkoAbstract:Abstract Avian chlamydiosis is a zoonotic disease occurring in humans, poultry, and exotic birds. It has been suggested that some wild bird species play an important role as reservoirs for Chlamydia, especially Chlamydia psittaci. Whereas C. psittaci is the predominant Chlamydial agent in birds, in the present study we have determined the prevalence of different species of Chlamydia among selected wild bird species in Poland using a rapid and sensitive real-time PCR method. In total, 369 free-living birds from 35 bird species and 15 orders were examined. Samples from 27 birds (7.3%) were positive for Chlamydial DNA in the PCR; 22 positive samples (81.5%) belonged to C. psittaci, three to Chlamydia trachomatis (11.1%), and two (7.4%) classified only to the genus Chlamydia. Most of C. psittaci–positive samples belonged to five orders: Anseriformes, Columbiformes, Gruiformes, Phasianiformes, and Passeriformes. All C. trachomatis samples were obtained from Eurasian coots (Gruiformes). Two Chlamydia-positive s...
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Prevalence of Chlamydia psittaci and Other Chlamydia Species in Wild Birds in Poland.
Vector-Borne and Zoonotic Diseases, 2015Co-Authors: Marta Krawiec, Tomasz Piasecki, Alina WieliczkoAbstract:Avian chlamydiosis is a zoonotic disease occurring in humans, poultry, and exotic birds. It has been suggested that some wild bird species play an important role as reservoirs for Chlamydia, especially Chlamydia psittaci. Whereas C. psittaci is the predominant Chlamydial agent in birds, in the present study we have determined the prevalence of different species of Chlamydia among selected wild bird species in Poland using a rapid and sensitive real-time PCR method. In total, 369 free-living birds from 35 bird species and 15 orders were examined. Samples from 27 birds (7.3%) were positive for Chlamydial DNA in the PCR; 22 positive samples (81.5%) belonged to C. psittaci, three to Chlamydia trachomatis (11.1%), and two (7.4%) classified only to the genus Chlamydia. Most of C. psittaci-positive samples belonged to five orders: Anseriformes, Columbiformes, Gruiformes, Phasianiformes, and Passeriformes. All C. trachomatis samples were obtained from Eurasian coots (Gruiformes). Two Chlamydia-positive samples not classified to any Chlamydia species were obtained from a common wood pigeon (Columbiformes) and a common buzzard (Accipitriformes). Detection of C. psittaci and C. trachomatis in free-living bird populations force to think on significance of birds as reservoir of varied Chlamydia species and their epidemiological importance.
Walter E. Stamm - One of the best experts on this subject based on the ideXlab platform.
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horizontal transfer of tetracycline resistance among Chlamydia spp in vitro
Antimicrobial Agents and Chemotherapy, 2009Co-Authors: Robert J Suchland, Walter E. Stamm, Kelsi M Sandoz, Brendan M Jeffrey, Daniel D RockeyAbstract:Members of the Chlamydiae are obligately intracellular bacteria that cause serious diseases in a wide variety of hosts (19). In humans, Chlamydia trachomatis causes trachoma and a variety of sexually transmitted conditions, diseases that affect millions of people around the world (25). Two related species, Chlamydia suis and Chlamydia muridarum, cause diseases of mucosal membranes in pigs and mice, respectively. A second genus within the Chlamydiae includes the more distantly related guinea pig pathogen Chlamydophila caviae and the human pathogen Chlamydophila pneumoniae. While the members of the Chlamydiae are generally similar in many aspects of basic biology, including genome order and gene content, there are differences in their intracellular survival strategies. One of these differences is the ability to form fusogenic inclusions. Wild-type strains of the Chlamydia spp. form intracellular vacuoles (termed inclusions) that undergo homotypic fusion (30), while no tested strains of these species form inclusions that fuse with inclusions of Chlamydophila caviae or Chlamydophila pneumoniae (23) (see Fig. Fig.1)1) (unpublished data). FIG. 1. Immunofluorescence images of McCoy cells coinfected with C. suis R19/tetR and C. muridarum MoPn/oflR (A) or with C. suis R19/tetR and Chlamydophila caviae GPIC/rifR (B). In both panels, C. suis R19/tetR is labeled red, while the alternate species is labeled ... The genome sequences of most Chlamydial species do not contain examples of recent horizontal acquisition of DNA. To date, the only reported example of a genomic island within any species of Chlamydia is the tet(C) island of C. suis. This island contains a C. suis-specific insertion element (IScs605), plasmid sequence with roots in gram-negative bacteria, and a tet(C) resistance gene (10). The tetracycline-resistant strains are common in swine herds in the United States (1) and recently have been identified in pigs from Italy (8). The strains carrying this island are the only examples of naturally acquired antibiotic resistance in any Chlamydial species. The C. suis tetracycline-resistant strains are also resistant to doxycycline, one of two contemporary front-line drugs of choice against Chlamydial infection in humans. Because of its low cost, tetracycline is also used to treat millions of cases of trachoma in developing countries (20). Although there are reports of drug resistance in strains collected from patients suffering treatment failure, documented stable homotypic drug resistance to antibiotics used for treating acute human Chlamydial infections is controversial (18, 24, 28). Transfer of a stable tetracycline-resistant phenotype to human clinical Chlamydiae would represent a significant public health challenge. The very limited examples of horizontally acquired DNA in the Chlamydiae support a hypothesis that recombination might be rare in this system. However, accumulating sequence data indicate that Chlamydia spp. are actively recombinogenic within a species. Early sequencing studies identified ompA variants that encode protein sequences from different classical serovars and showed that recombination may also occur at other locations in the chromosome (2, 11, 17, 21). Additionally, recent studies demonstrated conclusively that lateral gene transfer can be selected for in C. trachomatis in cell culture following coinfection with strains that have dissimilar drug resistance markers (6, 7). The mechanism of transfer in any of these recombination events remains to be elucidated. In order to explore possible tools for the development of a workable genetic system for directed mutagenesis of Chlamydia DNA, and to investigate the possibility of tetracycline resistance acquisition in human strains of C. trachomatis, we conducted in vitro recombination experiments using rifampin (rifampicin)-, ofloxacin-, and tetracycline-resistant strains as donors and recipients. Our results demonstrate that recombination can be readily demonstrated within and among species of the genus Chlamydia and that tetracycline resistance can be manifested by C. trachomatis following coculture with tetracycline-resistant C. suis strains. Tetracycline resistance was not successfully transferred to Chlamydophila caviae, suggesting a biological barrier that does not allow recombination across these genera.
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Rifalazil Pretreatment of Mammalian Cell Cultures Prevents Subsequent Chlamydia Infection
Antimicrobial Agents and Chemotherapy, 2006Co-Authors: Robert J Suchland, David M. Rothstein, Kara Brown, Walter E. StammAbstract:Chlamydia species are widely disseminated obligate intracellular pathogens that primarily cause urogenital, ocular, and respiratory infections. In these studies, we show that exposing mammalian cells to antibacterial agents prior to Chlamydia inoculation protects the host cells against subsequent challenge by Chlamydiae (the protective effect [PE]). Rifalazil exhibited a considerably stronger PE than did azithromycin, rifampin, doxycycline, and ofloxacin. Specifically, 0.002 μg/ml rifalazil incubated for 1 day with a monolayer of McCoy cells was sufficient to protect against a challenge 2 days later with Chlamydia trachomatis serovar D (UW-3). The PE was observed with five different mammalian cell lines and with a variety of C. trachomatis and Chlamydia pneumoniae isolates. The duration of the PE was 6 to 12 days for rifalazil (depending on the cell line), a maximum of 3 days for azithromycin, and less than a day for the other drugs tested. For rifalazil, the PE was shown to be mediated by inhibition of the Chlamydial RNA polymerase since mutants with altered RNA polymerases had correspondingly altered PEs. These results suggest that rifalazil may be unique in its ability to prevent infection with obligate intracellular pathogens for a considerable time after treatment. This characteristic may be of particular public health value in reducing reinfection with Chlamydiae.
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Use of a urine enzyme immunoassay as a diagnostic tool for Chlamydia trachomatis urethritis in men.
Journal of Clinical Microbiology, 1991Co-Authors: Jane R. Schwebke, Agnes M Clark, M B Pettinger, P Nsubga, Walter E. StammAbstract:We collected first-voided urine specimens from 659 males attending a sexually transmitted disease clinic and performed both enzyme immunoassay (EIA) for detection of Chlamydial antigen and leukocyte esterase testing on these urine samples. The overall prevalence of Chlamydial urethritis in the study population as determined by culture of urethral swabs was 11%. However, 46% of all men in the study had no symptoms of urethritis. Compared with urethral cultures for Chlamydiae, the urine EIA had a sensitivity of 42% and a specificity of 99%. The sensitivity of the EIA strongly correlated with the amount of antigen present in culture as assessed by numbers of inclusion-forming units. The sensitivity of the leukocyte esterase test compared with that of Chlamydia culture was 88%. We conclude that in this population of men, which included many patients without symptoms of urethritis, the urine EIA was a relatively insensitive means of screening for Chlamydial infection.