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Michel Drancourt - One of the best experts on this subject based on the ideXlab platform.
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Methanobrevibacter Smithii tonsillar phlegmon a case report
new microbes and new infections, 2021Co-Authors: K Djemai, Michel Drancourt, Frederique Gouriet, J Michel, T Radulesco, Ghiles GrineAbstract:Abstract Untreated tonsillar phlegmon is a life-threatening condition commonly caused by Streptococcus pyogenes and Fusobacterium necrophorum among other pathogens. Here using specific laboratory tools, we detected Methanobrevibacter Smithii in addition to S. pyogenes. This unprecedented observation questions the role of methanogens in phlegmon, and the optimal treatment of these mixed infection.
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meconial Methanobrevibacter Smithii suggests intrauterine methanogen colonization in preterm neonates
Current Research in Microbial Sciences, 2021Co-Authors: Youssouf Sereme, Michel Drancourt, Cheick Oumar Guindo, Anne Filleron, Pierre Corbeau, Tu Anh Tran, J Vitte, Ghiles GrineAbstract:ABSTRACT To understand the dynamics of methanogens in the human intestinal microbiota, we investigated the presence of methanogens in meconium using a polyphasic approach including microscopy and PCR-sequencing in 33 meconium samples collected from 33 pre-term neonates, in accordance with current ethics regulation. In the presence of negative controls, 90.9% samples were real-time PCR-positive for methanogens and 69.7 % were PCR-sequencing positive, identified as Methanobrevibacter (M.) Smithii. Further, auto-fluorescent analysis detected methanogens in the two meconium samples analyzed, with a morphology suggesting M. Smithii. Multispacer Sequence Typing found M. Smithii genotypes ST1 and ST2, previously described as intestinal microbiota inhabitants. C-section delivery and non-use of peripartum antibiotics significantly correlated with PCR-detection of methanogens in meconium. These data position M. Smithii among the early inhabitants of the human gut, detectable immediately after birth and suggest the contribution of methanogens to the perinatal development of intestinal microbiota and physiology.
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Methanobrevibacter Smithii tonsillar phlegmon: a case report
'Elsevier BV', 2021Co-Authors: K Djemai, Michel Drancourt, Frederique Gouriet, J Michel, T Radulesco, Ghiles GrineAbstract:Untreated tonsillar phlegmon is a life-threatening condition commonly caused by Streptococcus pyogenes and Fusobacterium necrophorum, among other pathogens. Here, using specific laboratory tools, we detected Methanobrevibacter Smithii in addition to S. pyogenes. This unprecedented observation questions the role of methanogens in phlegmon and the optimal treatment of this mixed infection
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Meconial Methanobrevibacter Smithii Suggests Intrauterine Methanogen Colonization in Preterm Neonates
SSRN Electronic Journal, 2021Co-Authors: Youssouf Sereme, Michel Drancourt, Cheick Oumar Guindo, Anne Filleron, Pierre Corbeau, Tu Anh Tran, J Vitte, Ghiles GrineAbstract:Background: Methanogens are part of the human microbiota, the intestinal and oral microbiota. They have even been found in colostrum and breast milk, in vagina only in case of vaginosis and in urinary tract during urinary tract infections. They are present in humans from birth. Accordingly, the detection of methanogens in the meconium has not been reported. The objective of this work was to investigate the presence of methanogens in meconium. Methods: We used a polyphasic approach including microscopy and PCR sequencing in 33 meconium samples taken from 33 premature newborns, in accordance with current ethical regulations. Results: In the presence of negative controls, 90.9% samples were real-time PCR-positive for methanogens and 69.7% were PCR-sequencing positive, identified as Methanobrevibacter (M.) Smithii. Further, auto-fluorescent analysis detected methanogens in the two meconium samples analyzed, with a morphology suggesting M. Smithii. Multispacer Sequence Typing found M. Smithii genotypes ST1 and ST2, previously described as intestinal microbiota inhabitants. C-section delivery and non-use of peripartum antibiotics significantly correlated with PCR-detection of methanogens in meconium. Conclusion: These data position M. Smithii among the early inhabitants of the human gut, detectable immediately after birth and suggest the contribution of methanogens to the perinatal development of intestinal microbiota and physiology. Trial Registration: NCT02738411. Funding Statement: YS and COG benefit from PhD grants from the Fondation Mediterranee Infection, Marseille, France. This work was supported by the French Government under the «Investissements d’avenir» (Investments for the Future) program managed by the Agence Nationale de la Recherche (ANR, fr: National Agency for Research), (reference: Mediterranee Infection 10-IAHU-03). Declaration of Interests: The authors declare no competing interests in relation to this study. Outside this study, JV reports speaker and consultancy fees in the past 5 years from Meda Pharma (Mylan), Novartis, Sanofi, Thermo Fisher Scientific, outside the submitted work. Ethics Approval Statement: Written informed parental consent was obtained for each preterm. This research project was approved by the Ethics Committee on Clinical Research of Nimes and Montpellier University Hospitals.
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Detection of Methanobrevobacter Smithii and Methanobrevibacter oralis in Lower Respiratory Tract Microbiota
Microorganisms, 2020Co-Authors: Yasmine Hassani, Michel Drancourt, F. Bregeon, Gérard Aboudharam, Ghiles GrineAbstract:Methanogens, the sole microbes producing methane, are archaea commonly found in human anaerobic microbiota. Methanogens are emerging as opportunistic pathogens associated with dysbiosis and are also detected and cultured in anaerobic abscesses. Their presence in the respiratory tract is yet unknown. As a preliminary answer, prospective investigation of 908 respiratory tract samples using polyphasic approach combining PCR-sequencing, real-time PCR, fluorescent in situ hybridization (FISH), and methanogens culture was carried out. Methanobrevibacter Smithii and Methanobrevibacter oralis DNA sequences, were detected in 21/527 (3.9%) sputum samples, 2/188 (1.06%) bronchoalveolar lavages, and none of 193 tracheo-bronchial aspirations. Further, fluorescence in situ hybridization detected methanogens in three sputum investigated specimens with stick morphology suggesting M. oralis and in another one bronchoalveolar lavage sample investigated, diplococal morphology suggesting M. Smithii. These observations extend the known territory of methanogens to the respiratory tract and lay the foundations for further interpretation of their detection as pathogens in any future cases of isolation from bronchoalveolar lavages and the lungs.
Didier Raoult - One of the best experts on this subject based on the ideXlab platform.
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co culture of Methanobrevibacter Smithii with enterobacteria during urinary infection
Social Science Research Network, 2019Co-Authors: Ghiles Grine, Romain Lotte, Alicia Chevalier, Daniela Chirio, Michel Drancourt, Didier Raoult, Raymond RuimyAbstract:Background: Urinary tract infections are known to be caused by bacteria, but the potential implications of archaea have never been studied in this context. Methods: In two different university hospital centres we used specific laboratory methods for the detection and culture of archaeal methanogens in 383 urine specimens prospectively collected for diagnosing urinary tract infection (UTI). Findings: Methanobrevibacter Smithii was detected by quantitative PCR and sequencing in 34 (9%) of the specimens collected from 34 patients. Escherichia coli, Klebsiella pneumoniae, Enterobacter sp., Enterococcus faecium and mixed cultures were detected along with M. Smithii in eighteen, six, three, one and six urine samples, respectively. Interestingly, using our specific culture method for methanogens, we also isolated M. Smithii in 31 (91%) of the 34 PCR positive urine samples. Genotyping the 31 isolates using multispacer sequence typing revealed three different genotypes which have been previously reported in intestinal microbiota. Antibiotic susceptibility testing found the 31 isolates to be in vitro susceptible to metronidazole (MIC: 1 mg/L) but resistant to fosfomycin, sulfamethoxazole-trimethoprim, amoxicillin-clavulanate and ofloxacin, commonly used to treat bacterial UTI. Finally, 19 (54%) of the 34 patients in whose urine samples M. Smithii was detected were diagnosed with UTIs, including cystitis, pyelonephritis and prostatitis. Interpretation: Our results show that M. Smithii is part of the urinary microbiota of some individuals and could play a role in community-acquired UTI in association with enteric bacteria. Funding: This study was supported by IHU Mediterranee Infection, Marseille, France. Declaration of Interest: The authors report no conflicts of interest. Ethical Approval: The study was approved by the Ethics Committee of the IHU Mediterranee Infection under n° 2016-01.
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Methanosphaera stadtmanae Detected in the Human Gut Using an Improved DNA Detection Protocol
2016Co-Authors: Amel Elkhéchine, Mireille Henry, Didier Raoult, Aix-marseille Université, Amel El Khéchine, Michel DrancourtAbstract:Background: The low and variable prevalence of Methanobrevibacter Smithii and Methanosphaera stadtmanae DNA in human stool contrasts with the paramount role of these methanogenic Archaea in digestion processes. We hypothesized that this contrast is a consequence of the inefficiencies of current protocols for archaeon DNA extraction. We developed a new protocol for the extraction and PCR-based detection of M. Smithii and M. stadtmanae DNA in human stool. Methodology/Principal Findings: Stool specimens collected from 700 individuals were filtered, mechanically lysed twice, and incubated overnight with proteinase K prior to DNA extraction using a commercial DNA extraction kit. Total DNA was used as a template for quantitative real-time PCR targeting M. Smithii and M. stadtmanae 16S rRNA and rpoB genes. Amplification of 16S rRNA and rpoB yielded positive detection of M. Smithii in 95.7 % and M. stadtmanae in 29.4 % of specimens. Sequencing of 16S rRNA gene PCR products from 30 randomly selected specimens (15 for M. Smithii and 15 for M. stadtmanae) yielded a sequence similarity of 99–100 % using the reference M. Smithii ATCC 35061 and M. stadtmanae DSM 3091 sequences. Conclusions/Significance: In contrast to previous reports, these data indicate a high prevalence of the methanogens M
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correlation between body mass index and gut concentrations of lactobacillus reuteri bifidobacterium animalis Methanobrevibacter Smithii and escherichia coli
International Journal of Obesity, 2013Co-Authors: Matthieu Million, Mireille Henry, M Maraninchi, R Valero, Bernard Vialettes, Emmanouil Angelakis, Roch Giorgi, Didier RaoultAbstract:Correlation between body mass index and gut concentrations of Lactobacillus reuteri , Bifidobacterium animalis , Methanobrevibacter Smithii and Escherichia coli
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a dna microarray for the versatile diagnosis of infectious diarrhea
Apmis, 2013Co-Authors: Emilie Donatin, Didier Raoult, Sylvain Buffet, Quentin Leroy, Michel DrancourtAbstract:Several bacteria, viruses, and parasites cause diarrhea as coinfecting pathogens. We designed a DNA microarray comprising 60-bp probes spotted 194 times for the multiplex detection of 33 enteropathogenic bacteria and seven enteropathogenic viruses, and the archaeon Methanobrevibacter Smithii was used as an internal positive control. Nine pathogen-free stool specimens were used as negative controls. One of these control specimens was further spiked with Salmonella enterica as a positive control. The microarray was then tested with 40 pathological stool specimens, comprising S. enterica (n = 30), Campylobacter jejuni (n = 4), pathogenic Escherichia coli (n = 2), and adenovirus (n = 4). M. Smithii was detected in 47/49 (95.9%) specimens, no pathogen was detected in negative controls and S. enterica was identified in the S. enterica-spiked positive control. The overall specificity was 100% and the overall sensitivity was 97.5% because one S. enterica sample was missed by the microarray. The multiplexed detection of C. jejuni spiked into an adenovirus-positive stool sample gave positive results, with fluorescence values of 14.3 and 9.1, respectively. These data indicate that using the protocol developed in this article, the DNA array allows for the multiplexed detection of some enteropathogens in stool samples.
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Growth monitoring of the five human-associated archaea strains by monitoring the CH4 production and H2 used by methanogens growing in culture medium SAB-medium or the standard DSMZ media.
2013Co-Authors: Saber Khelaifia, Didier Raoult, Michel DrancourtAbstract:A: Methanobrevibacter Smithii; B: Methanobrevibacter oralis; C: Methanosphaera stadtmanae; D: Methanomassilicoccus luminyensis; E: Methanobrevibacter arboriphilicus (Triplicate experiment).
Mark Pimentel - One of the best experts on this subject based on the ideXlab platform.
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methane and hydrogen positivity on breath test is associated with greater body mass index and body fat
The Journal of Clinical Endocrinology and Metabolism, 2013Co-Authors: Ruchi Mathur, Gillian M Barlow, M Amichai, Kathleen Shari Chua, James Mirocha, Mark PimentelAbstract:Context: Colonization of the gastrointestinal tract with methanogenic archaea (methanogens) significantly affects host metabolism and weight gain in animal models, and breath methane is associated with a greater body mass index (BMI) among obese human subjects. Objective: The objective of the study was to characterize the relationship between methane and hydrogen on breath test (as a surrogate for colonization with the hydrogen requiring methanogen, Methanobrevibacter Smithii), body weight, and percent body fat in a general population cohort. Design and Subjects: This was a prospective study (n = 792) of consecutive subjects presenting for breath testing. Setting: The study was conducted at a tertiary care center. Outcome Measurements: BMI and percent body fat were measured. Results: Subjects were classified into 4 groups based on breath testing: normal (N) (methane <3 ppm and hydrogen <20 ppm at or before 90 minutes); hydrogen positive only (H+) [methane <3 ppm and hydrogen ≥20 ppm); methane positive onl...
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intestinal Methanobrevibacter Smithii but not total bacteria is related to diet induced weight gain in rats
Obesity, 2012Co-Authors: Ruchi Mathur, Gene Kim, Walter Morales, Stacy Weitsman, Christopher Chang, Jaekyu Sung, Emily Rooks, Venkata B Pokkunuri, Gillian M Barlow, Mark PimentelAbstract:It is increasingly understood that gastrointestinal (GI) methanogens, including Methanobrevibacter Smithii, influence host metabolism. Objective: Therefore, we compared M. Smithii colonization and weight gain in a rat model under different dietary conditions. Design and Methods: Sprague-Dawley rats were inoculated with M. Smithii or vehicle (N = 10/group), fed normal chow until day 112 postinoculation, high-fat chow until day 182, then normal chow until day 253. Thereafter, five rats from each group were fed high-fat and normal chow until euthanasia. Results: Both groups exhibited M. Smithii colonization, which increased following inoculation only for the first 9 days. Change to high-fat chow correlated with significant increases in weight (P < 0.00001) and stool M. Smithii (P < 0.01) in all rats, with stool M. smithi decreasing on return to normal chow. Rats switched back to high-fat on day 253 further increased weight (P < 0.001) and stool M. Smithii (P = 0.039). Euthanasia revealed all animals had higher M. Smithii, but not total bacteria, in the small intestine than in the colon. Rats switched back to high-fat chow had higher M. Smithii levels in the duodenum, ileum, and cecum than those fed normal chow; total bacteria did not differ in any bowel segment. Rats which gained more weight had more bowel segments colonized, and the lowest weight recorded was in a rat on high-fat chow which had minimal M. Smithii colonization. Conclusions: We conclude that M. Smithii colonization occurs in the small bowel as well as in the colon, and that the level and extent of M. Smithii colonization is predictive of degree of weight gain in this animal model.
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Methanobrevibacter Smithii is the predominant methanogen in patients with constipation-predominant IBS and methane on breath.
Digestive diseases and sciences, 2012Co-Authors: Gene Kim, Fnu Deepinder, Walter Morales, Laura Hwang, Stacy Weitsman, Christopher Chang, Robert P. Gunsalus, Mark PimentelAbstract:Purpose Among irritable bowel syndrome (IBS) patients, breath methane producers overwhelmingly have constipation predominance (C-IBS). Although the most common methanogen in humans is Methanobrevibacter Smithii, incidence and type of methanogenic bacteria in C-IBS patients are unknown.
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T1832 Methanobrevibacter Smithii is Prominent in Stool of Subjects With Constipation Predominant IBS and Methane on Lactulose Breath Test
Gastroenterology, 2010Co-Authors: Gene Kim, Laura Hwang, Stacy Weitsman, Christopher Chang, Jim Y. Chou, Janet Yang, Kimberly Low, Mark PimentelAbstract:G A A b st ra ct s disease with hepatocellular carcinoma (HCC). Microsporidial infection was positive on wet preparation in 8(2.7%), in 11(3.7%) on Trichrome staining and in 13(4.3%) on PCR. Microsporidia was diagnosed with PCR in 8(61%) (p= 0.002) with IBS-D, 4(31%) with HCC and 1(8%) with functional dyspepsia. Conclusion: Microsporidial infection may be associated with IBS-D. PCR for microsporidia has a better yield than examination of a wet preparation or Trichrome staining
Matthieu Million - One of the best experts on this subject based on the ideXlab platform.
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increased gut redox and depletion of anaerobic and methanogenic prokaryotes in severe acute malnutrition
Scientific Reports, 2016Co-Authors: Matthieu Million, Jean Christophe Lagier, Maryam Tidjani Alou, Saber Khelaifia, Dipankar Bachar, Niokhor Dione, S Brah, Perrine Hugon, Vincent LombardAbstract:Severe acute malnutrition (SAM) is associated with inadequate diet, low levels of plasma antioxidants and gut microbiota alterations. The link between gut redox and microbial alterations, however, remains unexplored. By sequencing the gut microbiomes of 79 children of varying nutritional status from three centers in Senegal and Niger, we found a dramatic depletion of obligate anaerobes in malnutrition. This was confirmed in an individual patient data meta-analysis including 107 cases and 77 controls from 5 different African and Asian countries. Specifically, several species of the Bacteroidaceae, Eubacteriaceae, Lachnospiraceae and Ruminococceae families were consistently depleted while Enterococcus faecalis, Escherichia coli and Staphylococcus aureus were consistently enriched. Further analyses on our samples revealed increased fecal redox potential, decreased total bacterial number and dramatic Methanobrevibacter Smithii depletion. Indeed, M. Smithii was detected in more than half of the controls but in none of the cases. No causality was demonstrated but, based on our results, we propose a unifying theory linking microbiota specificity, lacking anaerobes and archaea, to low antioxidant nutrients, and lower food conversion.
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increased gut redox and depletion of anaerobic and methanogenic prokaryotes in severe acute malnutrition
Scientific Reports, 2016Co-Authors: Matthieu Million, Jean Christophe Lagier, Maryam Tidjani Alou, S Khelaifia, Dipankar Bachar, Niokhor Dione, S Brah, Perrine Hugon, Vincent LombardAbstract:Severe acute malnutrition (SAM) is associated with inadequate diet, low levels of plasma antioxidants and gut microbiota alterations. The link between gut redox and microbial alterations, however, remains unexplored. By sequencing the gut microbiomes of 79 children of varying nutritional status from three centers in Senegal and Niger, we found a dramatic depletion of obligate anaerobes in malnutrition. This was confirmed in an individual patient data meta-analysis including 107 cases and 77 controls from 5 different African and Asian countries. Specifically, several species of the Bacteroidaceae, Eubacteriaceae, Lachnospiraceae and Ruminococceae families were consistently depleted while Enterococcus faecalis, Escherichia coli and Staphylococcus aureus were consistently enriched. Further analyses on our samples revealed increased fecal redox potential, decreased total bacterial number and dramatic Methanobrevibacter Smithii depletion. Indeed, M. Smithii was detected in more than half of the controls but in none of the cases. No causality was demonstrated but, based on our results, we propose a unifying theory linking microbiota specificity, lacking anaerobes and archaea, to low antioxidant nutrients, and lower food conversion.
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correlation between body mass index and gut concentrations of lactobacillus reuteri bifidobacterium animalis Methanobrevibacter Smithii and escherichia coli
International Journal of Obesity, 2013Co-Authors: Matthieu Million, Mireille Henry, M Maraninchi, R Valero, Bernard Vialettes, Emmanouil Angelakis, Roch Giorgi, Didier RaoultAbstract:Correlation between body mass index and gut concentrations of Lactobacillus reuteri , Bifidobacterium animalis , Methanobrevibacter Smithii and Escherichia coli
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obesity associated gut microbiota is enriched in lactobacillus reuteri and depleted in bifidobacterium animalis and Methanobrevibacter Smithii
International Journal of Obesity, 2012Co-Authors: Matthieu Million, Mireille Henry, M Maraninchi, Fabrice Armougom, Herve Richet, Patrizia Carrieri, R Valero, Denis Raccah, Bernard VialettesAbstract:Obesity-associated gut microbiota is enriched in Lactobacillus reuteri and depleted in Bifidobacterium animalis and Methanobrevibacter Smithii
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obesity associated gut microbiota is enriched in lactobacillus reuteri and depleted in bifidobacterium animalis and Methanobrevibacter Smithii
International Journal of Obesity, 2012Co-Authors: Matthieu Million, Mireille Henry, M Maraninchi, Fabrice Armougom, Herve Richet, Patrizia Carrieri, R Valero, Denis Raccah, Bernard VialettesAbstract:BACKGROUND: Obesity is associated with increased health risk and has been associated with alterations in bacterial gut microbiota, with mainly a reduction in Bacteroidetes, but few data exist at the genus and species level. It has been reported that the Lactobacillus and Bifidobacterium genus representatives may have a critical role in weight regulation as an anti-obesity effect in experimental models and humans, or as a growth-promoter effect in agriculture depending on the strains. OBJECTIVES AND METHODS: To confirm reported gut alterations and test whether Lactobacillus or Bifidobacterium species found in the human gut are associated with obesity or lean status, we analyzed the stools of 68 obese and 47 controls targeting Firmicutes, Bacteroidetes, Methanobrevibacter Smithii, Lactococcus lactis, Bifidobacterium animalis and seven species of Lactobacillus by quantitative PCR (qPCR) and culture on a Lactobacillus-selective medium. FINDINGS: In qPCR, B. animalis (odds ratio (OR)=0.63; 95% confidence interval (CI) 0.39-1.01; P=0.056) and M. Smithii (OR=0.76; 95% CI 0.59-0.97; P=0.03) were associated with normal weight whereas Lactobacillus reuteri (OR=1.79; 95% CI 1.03-3.10; P=0.04) was associated with obesity. CONCLUSION: The gut microbiota associated with human obesity is depleted in M. Smithii. Some Bifidobacterium or Lactobacillus species were associated with normal weight (B. animalis) while others (L. reuteri) were associated with obesity. Therefore, gut microbiota composition at the species level is related to body weight and obesity, which might be of relevance for further studies and the management of obesity. These results must be considered cautiously because it is the first study to date that links specific species of Lactobacillus with obesity in humans.
Ghiles Grine - One of the best experts on this subject based on the ideXlab platform.
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Methanobrevibacter Smithii tonsillar phlegmon a case report
new microbes and new infections, 2021Co-Authors: K Djemai, Michel Drancourt, Frederique Gouriet, J Michel, T Radulesco, Ghiles GrineAbstract:Abstract Untreated tonsillar phlegmon is a life-threatening condition commonly caused by Streptococcus pyogenes and Fusobacterium necrophorum among other pathogens. Here using specific laboratory tools, we detected Methanobrevibacter Smithii in addition to S. pyogenes. This unprecedented observation questions the role of methanogens in phlegmon, and the optimal treatment of these mixed infection.
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meconial Methanobrevibacter Smithii suggests intrauterine methanogen colonization in preterm neonates
Current Research in Microbial Sciences, 2021Co-Authors: Youssouf Sereme, Michel Drancourt, Cheick Oumar Guindo, Anne Filleron, Pierre Corbeau, Tu Anh Tran, J Vitte, Ghiles GrineAbstract:ABSTRACT To understand the dynamics of methanogens in the human intestinal microbiota, we investigated the presence of methanogens in meconium using a polyphasic approach including microscopy and PCR-sequencing in 33 meconium samples collected from 33 pre-term neonates, in accordance with current ethics regulation. In the presence of negative controls, 90.9% samples were real-time PCR-positive for methanogens and 69.7 % were PCR-sequencing positive, identified as Methanobrevibacter (M.) Smithii. Further, auto-fluorescent analysis detected methanogens in the two meconium samples analyzed, with a morphology suggesting M. Smithii. Multispacer Sequence Typing found M. Smithii genotypes ST1 and ST2, previously described as intestinal microbiota inhabitants. C-section delivery and non-use of peripartum antibiotics significantly correlated with PCR-detection of methanogens in meconium. These data position M. Smithii among the early inhabitants of the human gut, detectable immediately after birth and suggest the contribution of methanogens to the perinatal development of intestinal microbiota and physiology.
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Meconial Methanobrevibacter Smithii Suggests Intrauterine Methanogen Colonization in Preterm Neonates
SSRN Electronic Journal, 2021Co-Authors: Youssouf Sereme, Michel Drancourt, Cheick Oumar Guindo, Anne Filleron, Pierre Corbeau, Tu Anh Tran, J Vitte, Ghiles GrineAbstract:Background: Methanogens are part of the human microbiota, the intestinal and oral microbiota. They have even been found in colostrum and breast milk, in vagina only in case of vaginosis and in urinary tract during urinary tract infections. They are present in humans from birth. Accordingly, the detection of methanogens in the meconium has not been reported. The objective of this work was to investigate the presence of methanogens in meconium. Methods: We used a polyphasic approach including microscopy and PCR sequencing in 33 meconium samples taken from 33 premature newborns, in accordance with current ethical regulations. Results: In the presence of negative controls, 90.9% samples were real-time PCR-positive for methanogens and 69.7% were PCR-sequencing positive, identified as Methanobrevibacter (M.) Smithii. Further, auto-fluorescent analysis detected methanogens in the two meconium samples analyzed, with a morphology suggesting M. Smithii. Multispacer Sequence Typing found M. Smithii genotypes ST1 and ST2, previously described as intestinal microbiota inhabitants. C-section delivery and non-use of peripartum antibiotics significantly correlated with PCR-detection of methanogens in meconium. Conclusion: These data position M. Smithii among the early inhabitants of the human gut, detectable immediately after birth and suggest the contribution of methanogens to the perinatal development of intestinal microbiota and physiology. Trial Registration: NCT02738411. Funding Statement: YS and COG benefit from PhD grants from the Fondation Mediterranee Infection, Marseille, France. This work was supported by the French Government under the «Investissements d’avenir» (Investments for the Future) program managed by the Agence Nationale de la Recherche (ANR, fr: National Agency for Research), (reference: Mediterranee Infection 10-IAHU-03). Declaration of Interests: The authors declare no competing interests in relation to this study. Outside this study, JV reports speaker and consultancy fees in the past 5 years from Meda Pharma (Mylan), Novartis, Sanofi, Thermo Fisher Scientific, outside the submitted work. Ethics Approval Statement: Written informed parental consent was obtained for each preterm. This research project was approved by the Ethics Committee on Clinical Research of Nimes and Montpellier University Hospitals.
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Methanobrevibacter Smithii tonsillar phlegmon: a case report
'Elsevier BV', 2021Co-Authors: K Djemai, Michel Drancourt, Frederique Gouriet, J Michel, T Radulesco, Ghiles GrineAbstract:Untreated tonsillar phlegmon is a life-threatening condition commonly caused by Streptococcus pyogenes and Fusobacterium necrophorum, among other pathogens. Here, using specific laboratory tools, we detected Methanobrevibacter Smithii in addition to S. pyogenes. This unprecedented observation questions the role of methanogens in phlegmon and the optimal treatment of this mixed infection
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Detection of Methanobrevobacter Smithii and Methanobrevibacter oralis in Lower Respiratory Tract Microbiota
Microorganisms, 2020Co-Authors: Yasmine Hassani, Michel Drancourt, F. Bregeon, Gérard Aboudharam, Ghiles GrineAbstract:Methanogens, the sole microbes producing methane, are archaea commonly found in human anaerobic microbiota. Methanogens are emerging as opportunistic pathogens associated with dysbiosis and are also detected and cultured in anaerobic abscesses. Their presence in the respiratory tract is yet unknown. As a preliminary answer, prospective investigation of 908 respiratory tract samples using polyphasic approach combining PCR-sequencing, real-time PCR, fluorescent in situ hybridization (FISH), and methanogens culture was carried out. Methanobrevibacter Smithii and Methanobrevibacter oralis DNA sequences, were detected in 21/527 (3.9%) sputum samples, 2/188 (1.06%) bronchoalveolar lavages, and none of 193 tracheo-bronchial aspirations. Further, fluorescence in situ hybridization detected methanogens in three sputum investigated specimens with stick morphology suggesting M. oralis and in another one bronchoalveolar lavage sample investigated, diplococal morphology suggesting M. Smithii. These observations extend the known territory of methanogens to the respiratory tract and lay the foundations for further interpretation of their detection as pathogens in any future cases of isolation from bronchoalveolar lavages and the lungs.