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Sanjay K. Shukla - One of the best experts on this subject based on the ideXlab platform.
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Complete Genome Sequence of a Staphylococcus epidermidis Bacteriophage Isolated from the Anterior Nares of Humans
Genome announcements, 2014Co-Authors: Vijay Aswani, Denise M. Tremblay, Sylvain Moineau, Sanjay K. ShuklaAbstract:ABSTRACT We report here the complete genome sequence of a virulent Staphylococcus epidermidis siphophage, phage 6ec, isolated from the Anterior Nares of a human. This viral genome is 93,794 bp in length, with a 3′ overhang cos site of 10 nucleotides, and it codes for 142 putative open reading frames.
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Staphylococcus epidermidis bacteriophages from the Anterior Nares of humans.
Applied and environmental microbiology, 2011Co-Authors: Vijay Aswani, Denise M. Tremblay, Sylvain Moineau, Sanjay K. ShuklaAbstract:The role of virulent bacteriophages in staphylococcal colonization of the human Anterior Nares is not known. This report of lytic bacteriophages against Staphylococcus epidermidis in the Anterior Nares of 5.5% of human subjects (n = 202) suggests their potential role in modulating staphylococcal colonization in this ecological niche.
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Prevalence of Staphylococcus aureus and Lack of Its Lytic Bacteriophages in the Anterior Nares of Patients and Healthcare Workers at a Rural Clinic
Clinical medicine & research, 2010Co-Authors: Vijay Aswani, Sanjay K. ShuklaAbstract:Background: Nearly 30% of people in the United States are colonized with Staphylococcus aureus and 1% to 2% with methicillin-resistant Staphylococcus aureus (MRSA) in the Anterior Nares. However, it is not known if lytic bacteriophages against S. aureus are present in the Anterior Nares, and if they are, what the prevalence rate is, or if they interfere with S. aureus colonization. The aim of this study was to determine the prevalence of nasal carriage of S. aureus and MRSA and to screen for S. aureus lytic bacteriophages in healthcare environment workers and ambulatory patients. Methods: We enrolled 202 individuals into this study. The Anterior Nares were swabbed to isolate S. aureus, MRSA, and any lytic S. aureus bacteriophages that may be present. Putative S. aureus colonies on blood agar plates were identified using gram stain, catalase and coagulase tests, and confirmed by S. aureus-specific PCR. Presence of staphylococcal lytic bacteriophages were screened by a plaque assay technique using a methicillin-sensitive reference S. aureus strain ATCC 29213. Results: Of the 49 (24%) individuals who screened positive for S. aureus, two (1%) were positive for MRSA. None of the samples were positive for lytic bacteriophages against S. aureus. Subgroup analysis found no significant difference in the prevalence of S. aureus in the house staff compared to other healthcare environment workers or ambulatory patients of the clinic. Similarly, no significant difference in colonization was noted across the population with respect to age, sex, body mass index, or presence of diabetes mellitus. Conclusion: The prevalence of nasal carriage of S. aureus and MRSA in the studied population was 24% and 1%, respectively, similar to the rate of prevalence in the United States. The study also showed that the Anterior Nares do not seem to harbor lytic bacteriophages against S. aureus.
Jaime Bustos-martínez - One of the best experts on this subject based on the ideXlab platform.
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Genotypic characterization of methicillin-resistant Staphylococcus aureus strains isolated from the Anterior Nares and catheter of ambulatory hemodialysis patients in Mexico
Folia Microbiologica, 2014Co-Authors: Gloria Paniagua-contreras, Eric Monroy-pérez, Raúl Gutiérrez-lucas, Teresita Sainz-espuñes, Jaime Bustos-martínez, Sergio VacaAbstract:Methicillin-resistant Staphylococcus aureus (MRSA) is the causal agent of multiple nosocomial infections worldwide, including catheter-associated bacteremia in hemodialysis patients. The purposes of this work were to genetically characterize a group of MRSA isolates from catheter-related infections of ambulatory Mexican hemodialysis patients and to determine whether the strains are the same as those carried by the patients in their Anterior Nares. Sixteen pairs of MRSA isolates from the catheter (cat) and Anterior Nares (N) of hemodialysis patients were compared using pulsed-field gel electrophoresis (PFGE), PCR detection of adhesion genes and other virulence markers, and an antibiogram. Three pairs of N/cat MRSA isolates (18.7 %) with identical resistograms also showed the same combination of PCR-detected markers and PFGE pattern; one additional pair showed only an identical electrophoretic PFGE pattern. Of the MRSA isolates, 75 % ( n = 24) were resistant to ≥7 antibiotics, 4 isolates were resistant to 11 antibiotics, and 7 isolates were resistant to the 12 antibiotics tested. The most frequent virulence marker combination found was spa , clfA , clfB , cna , bbp , ebps , map / eap , sdrC , sdrD , sdrE , ica , agr (65.6 %, n = 21). The SCC mec alleles of the 32 MRSA isolates were IV ( n = 20), I ( n = 7), II ( n = 4), and V ( n = 1), and no SCC mec type III MRSA was found. The genotypic characterization of the MRSA isolates studied in this work will contribute to a better understanding of the virulence gene makeup of catheter-colonizing S. aureus strains and will help to lower the infection risk in these patients.
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Characterization and Persistence of Staphylococcus aureus Strains Isolated from the Anterior Nares and Throats of Healthy Carriers in a Mexican Community
Journal of clinical microbiology, 2010Co-Authors: Aida Hamdan-partida, Teresita Sainz-espuñes, Jaime Bustos-martínezAbstract:Healthy carriers of Staphylococcus aureus strains have an important role in the dissemination of this bacterium. To investigate the presence of S. aureus in the throat and Anterior Nares, samples from 1,243 healthy volunteers in a Mexican community were examined. The percentage of healthy carriers was 59.8%. Results showed that colonization of the throat occurred more frequently than that of the Nares (46.5% versus 37.1%, P < 0.0001). Of the S. aureus carriers, 22.2% were exclusive nasal carriers and 38% were exclusive throat carriers. A total of 1,039 strains were isolated; 12.6% were shown to be methicillin-resistant S. aureus (MRSA). Of MRSA strains, 32.1% were isolated from exclusive throat carriers. Most of the strains isolated from the Anterior Nares and throat of the same carriers were the same or related; however, some were different. Pulsed-field gel electrophoresis (PFGE) pattern analysis of the MRSA strains isolated from the exclusive nasal carriers or exclusive throat carriers showed that they belong to different clusters. A 6-year prospective study was performed to investigate the persistence of S. aureus in the throat. Results showed that 13% of subjects were persistent carriers. Most of them were colonized with the same clone of S. aureus throughout the time of the study, and just three had different clones. Antimicrobial susceptibility testing showed that 91.1% of the strains were penicillin resistant. The presence of mecA and nucA genes (in order to confirm methicillin resistance) and of thermostable nuclease of S. aureus was examined. This study showed that some strains of S. aureus regularly colonized the throats of healthy people and could persist for years.
Georg Peters - One of the best experts on this subject based on the ideXlab platform.
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nasal carriage as a source of staphylococcus aureus bacteremia
The New England Journal of Medicine, 2009Co-Authors: Christof Von Eiff, Karsten Becker, Konstanze Machka, Holger Stammer, Georg PetersAbstract:Background The consequences of infection with Staphylococcus aureus can be severe, so strategies for prevention are important. We examined S. aureus isolates from blood and from nasal specimens to determine whether the organisms in the bloodstream originated from the patient's own flora. Methods In a multicenter study, swabs for culture were obtained from the Anterior Nares of 219 patients with S. aureus bacteremia. A total of 723 isolates were collected and genotyped. In a second study, 1640 S. aureus isolates from nasal swabs from 1278 patients were collected over a period of five years and then compared with isolates from the blood of patients who subsequently had S. aureus bacteremia. Results In the multicenter study of S. aureus bacteremia, the blood isolates were identical to those from the Anterior Nares in 180 of 219 patients (82.2 percent). In the second study, 14 of 1278 patients who had nasal colonization with S. aureus subsequently had S. aureus bacteremia. In 12 of these 14 patients (86 perce...
Vijay Aswani - One of the best experts on this subject based on the ideXlab platform.
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Complete Genome Sequence of a Staphylococcus epidermidis Bacteriophage Isolated from the Anterior Nares of Humans
Genome announcements, 2014Co-Authors: Vijay Aswani, Denise M. Tremblay, Sylvain Moineau, Sanjay K. ShuklaAbstract:ABSTRACT We report here the complete genome sequence of a virulent Staphylococcus epidermidis siphophage, phage 6ec, isolated from the Anterior Nares of a human. This viral genome is 93,794 bp in length, with a 3′ overhang cos site of 10 nucleotides, and it codes for 142 putative open reading frames.
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Staphylococcus epidermidis bacteriophages from the Anterior Nares of humans.
Applied and environmental microbiology, 2011Co-Authors: Vijay Aswani, Denise M. Tremblay, Sylvain Moineau, Sanjay K. ShuklaAbstract:The role of virulent bacteriophages in staphylococcal colonization of the human Anterior Nares is not known. This report of lytic bacteriophages against Staphylococcus epidermidis in the Anterior Nares of 5.5% of human subjects (n = 202) suggests their potential role in modulating staphylococcal colonization in this ecological niche.
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Prevalence of Staphylococcus aureus and Lack of Its Lytic Bacteriophages in the Anterior Nares of Patients and Healthcare Workers at a Rural Clinic
Clinical medicine & research, 2010Co-Authors: Vijay Aswani, Sanjay K. ShuklaAbstract:Background: Nearly 30% of people in the United States are colonized with Staphylococcus aureus and 1% to 2% with methicillin-resistant Staphylococcus aureus (MRSA) in the Anterior Nares. However, it is not known if lytic bacteriophages against S. aureus are present in the Anterior Nares, and if they are, what the prevalence rate is, or if they interfere with S. aureus colonization. The aim of this study was to determine the prevalence of nasal carriage of S. aureus and MRSA and to screen for S. aureus lytic bacteriophages in healthcare environment workers and ambulatory patients. Methods: We enrolled 202 individuals into this study. The Anterior Nares were swabbed to isolate S. aureus, MRSA, and any lytic S. aureus bacteriophages that may be present. Putative S. aureus colonies on blood agar plates were identified using gram stain, catalase and coagulase tests, and confirmed by S. aureus-specific PCR. Presence of staphylococcal lytic bacteriophages were screened by a plaque assay technique using a methicillin-sensitive reference S. aureus strain ATCC 29213. Results: Of the 49 (24%) individuals who screened positive for S. aureus, two (1%) were positive for MRSA. None of the samples were positive for lytic bacteriophages against S. aureus. Subgroup analysis found no significant difference in the prevalence of S. aureus in the house staff compared to other healthcare environment workers or ambulatory patients of the clinic. Similarly, no significant difference in colonization was noted across the population with respect to age, sex, body mass index, or presence of diabetes mellitus. Conclusion: The prevalence of nasal carriage of S. aureus and MRSA in the studied population was 24% and 1%, respectively, similar to the rate of prevalence in the United States. The study also showed that the Anterior Nares do not seem to harbor lytic bacteriophages against S. aureus.
Dietmar H. Pieper - One of the best experts on this subject based on the ideXlab platform.
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Bacterial community structure and effects of picornavirus infection on the Anterior Nares microbiome in early childhood
BMC Microbiology, 2019Co-Authors: Mahrrouz Caputo, Beate Zoch-lesniak, André Karch, Marius Vital, Frederic Meyer, Frank Klawonn, Armin Baillot, Dietmar H. Pieper, Rafael T. MikolajczykAbstract:Background Little is known regarding the nasal microbiome in early childhood and the impact of respiratory infection on the infants’ nasal microbial composition. Here we investigated the temporal dynamics and diversity of the bacterial composition in the Anterior Nares in children attending daycare centers. Results For our investigation, we considered 76 parental-taken nasal swabs of 26 children (aged 13 to 36 months) collected over a study period of 3 months. Overall, there was no significant age-specific effect or seasonal shift in the nasal bacterial community structure. In a sub-sample of 14 healthy children the relative abundance of individual taxa as well as the overall diversity did not reveal relevant changes, indicating a stable community structure over the entire study period. Moreover, the nasal bacterial profiles clustered subject-specific with Bray-Curtis similarities being elevated in intra-subject calculations compared to between-subject calculations. The remaining subset of 12 children provided samples taken during picornavirus infection (PVI) and either before or after a PVI. We detected an association between the relative abundance of members of the genus Streptococcus and PV when comparing both (i) samples taken during PVI with samples out of 14 healthy children and (ii) samples taken during PVI with samples taken after PVI within the same individual. In addition, the diversity was higher during PVI than after infection. Conclusions Our findings suggest that a personalized structure of the nasal bacterial community is established already in early childhood and could be detected over a timeframe of 3 months. Studies following infants over a longer time with frequent swab sampling would allow investigating whether certain parameter of the bacterial community, such as the temporal variability, could be related to viral infection.
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Bacterial community structure and effects of picornavirus infection on the Anterior Nares microbiome in early childhood.
BMC microbiology, 2019Co-Authors: Mahrrouz Caputo, Beate Zoch-lesniak, André Karch, Marius Vital, Frederic Meyer, Frank Klawonn, Armin Baillot, Dietmar H. Pieper, Rafael T. MikolajczykAbstract:Little is known regarding the nasal microbiome in early childhood and the impact of respiratory infection on the infants’ nasal microbial composition. Here we investigated the temporal dynamics and diversity of the bacterial composition in the Anterior Nares in children attending daycare centers. For our investigation, we considered 76 parental-taken nasal swabs of 26 children (aged 13 to 36 months) collected over a study period of 3 months. Overall, there was no significant age-specific effect or seasonal shift in the nasal bacterial community structure. In a sub-sample of 14 healthy children the relative abundance of individual taxa as well as the overall diversity did not reveal relevant changes, indicating a stable community structure over the entire study period. Moreover, the nasal bacterial profiles clustered subject-specific with Bray-Curtis similarities being elevated in intra-subject calculations compared to between-subject calculations. The remaining subset of 12 children provided samples taken during picornavirus infection (PVI) and either before or after a PVI. We detected an association between the relative abundance of members of the genus Streptococcus and PV when comparing both (i) samples taken during PVI with samples out of 14 healthy children and (ii) samples taken during PVI with samples taken after PVI within the same individual. In addition, the diversity was higher during PVI than after infection. Our findings suggest that a personalized structure of the nasal bacterial community is established already in early childhood and could be detected over a timeframe of 3 months. Studies following infants over a longer time with frequent swab sampling would allow investigating whether certain parameter of the bacterial community, such as the temporal variability, could be related to viral infection.
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Exploring the transcriptome of Staphylococcus aureus in its natural niche.
Scientific reports, 2016Co-Authors: Diego Chaves-moreno, Ruy Jauregui, Melissa L. Wos-oxley, Eva Medina, Andrew P. A. Oxley, Dietmar H. PieperAbstract:Staphylococcus aureus is an important human pathogen and commensal, where the human nose is the predominant reservoir. To better understand its behavior in this environmental niche, RNA was extracted from the Anterior Nares of three documented S. aureus carriers and the metatranscriptome analyzed by RNAseq. In addition, the in vivo transcriptomes were compared to previously published transcriptomes of two in vitro grown S. aureus strains. None of the in vitro conditions, even growth in medium resembling the Anterior Nares environment, mimicked in vivo conditions. Survival in the nose was strongly controlled by the limitation of iron and evident by the expression of iron acquisition systems. S. aureus populations in different individuals clearly experience different environmental stresses, which they attempt to overcome by the expression of compatible solute biosynthetic pathways, changes in their cell wall composition and synthesis of general stress proteins. Moreover, the expression of adhesins was also important for colonization of the Anterior Nares. However, different S. aureus strains also showed different in vivo behavior. The assessment of general in vivo expression patterns and commonalities between different S. aureus strains will in the future result in new knowledge based strategies for controlling colonization.
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The temporal dynamics of bacterial communities across human Anterior Nares.
Environmental microbiology reports, 2011Co-Authors: Amélia Camarinha-silva, Ruy Jauregui, Dietmar H. Pieper, Melissa L. Wos-oxleyAbstract:The Anterior Nares (nostrils), are an important niche for bacterial colonization by both commensals and opportunistic pathogens. Here the temporal dynamics and variation of the global nasal bacterial community across 25 healthy volunteers was evaluated over 15 months. Overall, there was a global seasonal shift in bacterial community structure. Such a temporal shift was also strongly evident in the abundances of species such as Propionibacterium acnes and Staphylococcus epidermidis. However, such species dynamics over time was also inter-individual-dependent, and both individuals with highly stable communities and those with highly flexible communities could be defined. Even though the bacterial community of individual volunteers was thus generally variable over time and permanent carriage of a given species was seldomly observed, various species previously defined as constituting the core bacterial community could be identified as persistent in a subset of the volunteers suggesting that these same species also constitute to a 'temporal' core community.
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Validating T-RFLP as a sensitive and high-throughput approach to assess bacterial diversity patterns in human Anterior Nares.
FEMS microbiology ecology, 2011Co-Authors: Amélia Camarinha-silva, Ruy Jauregui, Melissa L. Wos-oxley, Karsten Becker, Dietmar H. PieperAbstract:While recent works aimed to thoroughly characterize the bacterial community of the human Anterior Nares of a few candidates, this work sought to analyse a greater cross-section by sampling 100 volunteers. After optimizing and validating the method of terminal restriction fragment length polymorphism against six previously pyrosequenced samples, abundant species could be discriminated and their relative abundances measured in a high-throughput manner. The 100 volunteers could be statistically clustered into 12 groups, where two-thirds of volunteers shared more than 40% similarity in respect to their bacterial community structure, while the remaining third clustered into smaller groups being dominated by Dolosigranulum pigrum, Moraxella spp. or Staphylococcus aureus. Moraxella spp. was present predominantly in women rather than in men. The use of network analysis charting bacterial ecological co-occurrences revealed new evidence of likely positive associations between some core human nasal species. So, in the age of post ‘omics’ and ‘deep sequencing’, there is still a place for these well-tried and well-tested methods that can offer a rapid, reproducible and economical alternative, whereby also yielding valuable new information.