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1.
Clin Microbiol Rev ; 35(3): e0014021, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-35658516

RESUMO

Candidate phyla radiation (CPR) is an emerging division of the bacterial domain within the human microbiota. Still poorly known, these microorganisms were first described in the environment in 1981 as "ultramicrobacteria" with a cell volume under 0.1 µm3 and were first associated with the human oral microbiota in 2007. The evolution of technology has been paramount for the study of CPR within the human microbiota. In fact, since these ultramicrobacteria have yet to be axenically cultured despite ongoing efforts, progress in imaging technology has allowed their observation and morphological description. Although their genomic abilities and taxonomy are still being studied, great strides have been made regarding their taxonomic classification, as well as their lifestyle. In addition, advancements in next-generation sequencing and the continued development of bioinformatics tools have allowed their detection as commensals in different human habitats, including the oral cavity and gastrointestinal and genital tracts, thus highlighting CPR as a nonnegligible part of the human microbiota with an impact on physiological settings. Conversely, several pathologies present dysbiosis affecting CPR levels, including inflammatory, mucosal, and infectious diseases. In this exhaustive review of the literature, we provide a historical perspective on the study of CPR, an overview of the methods available to study these organisms and a description of their taxonomy and lifestyle. In addition, their distribution in the human microbiome is presented in both homeostatic and dysbiotic settings. Future efforts should focus on developing cocultures and, if possible, axenic cultures to obtain isolates and therefore genomes that would provide a better understanding of these ultramicrobacteria, the importance of which in the human microbiome is undeniable.


Assuntos
Microbiota , Bactérias , Disbiose , Humanos , Boca/microbiologia
2.
Mycoses ; 65(7): 753-759, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35546294

RESUMO

BACKGROUND: Currently, Candida auris is among the most serious emerging pathogens that can be associated with nosocomial infections and outbreaks in intensive care units. Clinicians must be able to identify and manage it quickly. OBJECTIVE: Here, we report for the first time in Algeria seven cases of C. auris infection or colonisation. METHODS AND RESULTS: The strains were isolated from clinical sites including bronchial aspirates (n = 4), wound swabs (n = 1), urine sample (n = 1) and peritoneal fluid (n = 1), in patients admitted to the intensive care unit. Candida auris was identified both by MALDI-TOF and by sequencing the ITS region and the D1/D2 domain. Antifungal susceptibility testing was performed using the E-test method. Non-wildtype susceptibility was observed for five strains against fluconazole, itraconazole, voriconazole and caspofungin. Genotyping showed the presence of four clades (I-IV) in one hospital. CONCLUSIONS: Appropriate antifungal treatments with rapid and accurate microbial identification are the cornerstone for the management and control of C. auris infections.


Assuntos
Antifúngicos , Candidíase , Argélia/epidemiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida/genética , Candida auris , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana
3.
Int J Mol Sci ; 23(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35628255

RESUMO

The increased exploitation of microbial sequencing methods has shed light on the high diversity of new microorganisms named Candidate Phyla Radiation (CPR). CPR are mainly detected via 16S rRNA/metabarcoding analyses or metagenomics and are found to be abundant in all environments and present in different human microbiomes. These microbes, characterized by their symbiotic/epiparasitic lifestyle with bacteria, are directly exposed to competition with other microorganisms sharing the same ecological niche. Recently, a rich repertoire of enzymes with antibiotic resistance activity has been found in CPR genomes by using an in silico adapted screening strategy. This reservoir has shown a high prevalence of putative beta-lactamase-encoding genes. We expressed and purified five putative beta-lactamase sequences having the essential domains and functional motifs from class A and class B beta-lactamase. Their enzymatic activities were tested against various beta-lactam substrates using liquid chromatography-mass spectrometry (LC-MS) and showed some beta-lactamase activity even in the presence of a beta-lactamase inhibitor. In addition, ribonuclease activity was demonstrated against RNA that was not inhibited by sulbactam and EDTA. None of these proteins could degrade single- and double-stranded-DNA. This study is the first to express and test putative CPR beta-lactamase protein sequences in vitro. Our findings highlight that the reduced genomes of CPR members harbor sequences encoding for beta-lactamases known to be multifunction hydrolase enzymes.


Assuntos
Inibidores de beta-Lactamases , beta-Lactamases , Bactérias/genética , Bactérias/metabolismo , Humanos , RNA Ribossômico 16S/genética , beta-Lactamases/genética , beta-Lactamases/metabolismo , beta-Lactamas
4.
Eur J Clin Microbiol Infect Dis ; 40(7): 1547-1551, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33515096

RESUMO

Candida auris is an emerging multiresistant pathogen causing nosocomial fungal infection. Specific detection and identification are necessary. Our goal is to develop a new qPCR system that enables rapid detection of C. auris, based on a GPI (glycosyl-phosphatidylinositol) protein-encoding gene. This system is reproducible and sensitive with a limit of detection of 13 C. auris CFU/qPCR reaction. The 100% specificity of this system is confirmed on 2073 clinical and environmental samples, 50 different bacterial species, and 9 Candida spp. (70 strains). This system is suitable to correctly identify C. auris infections and to trace its source.


Assuntos
Candida/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Microbiologia Ambiental , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
5.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073251

RESUMO

Living organisms interact with each other during their lifetime, leading to genomes rearrangement and sequences transfer. These well-known phenomena give these organisms mosaic genomes, which challenge their classification. Moreover, many findings occurred between the IXXth and XXIst century, especially the discovery of giant viruses and candidate phyla radiation (CPR). Here, we tried to provide an updated classification, which integrates 216 representative genomes of the current described organisms. The reclassification was expressed through a genetic network based on the total genomic content, not on a single gene to represent the tree of life. This rhizomal exploration represents, more accurately, the evolutionary relationships among the studied species. Our analyses show a separated branch named fifth TRUC (Things Resisting Uncompleted Classifications). This taxon groups CPRs together, independently from Bacteria, Archaea (which regrouped also Nanoarchaeota and Asgard members), Eukarya, and the giant viruses (recognized recently as fourth TRUC). Finally, the broadening of analysis methods will lead to the discovery of new organisms, which justify the importance of updating the classification at every opportunity. In this perspective, our pragmatic representation could be adjusted along with the progress of evolutionary studies.


Assuntos
Archaea/classificação , Bactérias/classificação , Rizoma , Microbiologia do Solo , Vírus/classificação , Rizoma/microbiologia , Rizoma/virologia
6.
Arch Microbiol ; 202(5): 1223-1229, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32103285

RESUMO

A Gram-negative and facultative anaerobic bacterium, designated strain SN4T, was isolated from the stool sample of an obese Amazonian patient. The new isolate was characterized by the taxonogenomics approach. The strain SN4T was beige-colored, circular and not haemolytic. Cells are rod shaped and motile with several flagella. Strain SN4T grows optimally at pH 7 and can survive in the presence of a saline concentration of up to 75 g/l NaCl. The 16S ribosomal RNA gene sequence analysis of the novel strain SN4T showed 95.28% similarity in nucleotide sequence with Gorillibacterium massiliense G5T, the phylogenetically closest neighbor and the type species of this genus. Anteiso-C15:0, iso-C15:0 and C16:0 were found as the major components in the cellular fatty acid analysis of this isolate. The genomic draft of strain SN4T is 5,263,742 bp long with 53.33% of G+C content. The differences in physiological, biochemical characteristics and phylogenetic and genomic data make it possible to clearly distinguish the strain SN4T from G. massiliense G5T. Based on the taxonogenomic description and the phenotypic and biochemical characteristics of this bacterium presented in this article, we propose the SN4T strain (= CSUR P2011 = DSM 100,698) as a new species, Gorillibacterium timonense sp. nov.


Assuntos
Bacillales/classificação , Filogenia , Bacillales/genética , Bacillales/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Fezes/microbiologia , Genômica , Humanos , Obesidade , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
7.
Artigo em Inglês | MEDLINE | ID: mdl-31307986

RESUMO

The use of antifungal agents in clinical settings is limited by the appearance of drug resistance and adverse side effects. There is, therefore, an urgent need to develop new drugs to strengthen the treatment of invasive fungal diseases. The aim of this study is to describe the potential repurposing of ribavirin as an adjunct therapy against Candida spp. Primary screening of a Prestwick Chemical library against Candida albicans ATCC 90028 and fluconazole-resistant Candida albicans strains was performed. Subsequently, we evaluated the responses of 100 Candida sp. strains to ribavirin, an antiviral agent, using the broth microdilution method as recommended by CLSI. We checked the involvement of efflux pump activity in the development of ribavirin resistance. We studied time-kill curves and performed a checkerboard assay for a ribavirin-antifungal combination study. Twenty-one nonstandard antifungal compounds were identified, including ribavirin. Ribavirin had antifungal activity in vitro against 63 Candida strains, including strains of C. albicans, C. parapsilosis, and C. tropicalis, with MICs ranging from 0.37 to 3.02 µg/ml, while MICs for C. krusei, C. glabrata, C. lusitaniae, and some C. albicans strains remained high (≥24.16 µg/ml). No relation was observed between efflux pump activity and ribavirin resistance. Ribavirin exhibited fungistatic activity against multidrug-resistant (MDR) C. albicans and fungicidal activity against a C. parapsilosis strain. In addition, ribavirin acted synergistically with azoles against Candida strains for which ribavirin MICs were <24.4 µg/ml. This study highlights the potential clinical application of ribavirin, alone or in association with other antifungal agents, as an adjunct anti-Candida drug.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida parapsilosis/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Reposicionamento de Medicamentos , Farmacorresistência Fúngica/efeitos dos fármacos , Ribavirina/farmacologia , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida parapsilosis/genética , Candida parapsilosis/crescimento & desenvolvimento , Candida tropicalis/genética , Candida tropicalis/crescimento & desenvolvimento , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/microbiologia , Sinergismo Farmacológico , Fluconazol/farmacologia , Expressão Gênica , Genes MDR , Humanos , Testes de Sensibilidade Microbiana , Medicamentos sob Prescrição/farmacologia , Triazóis/farmacologia
8.
Arch Microbiol ; 201(10): 1361-1368, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31332473

RESUMO

Strain 6021061333T was isolated from the sputum of 16-year-old girl with cystic fibrosis following a pulmonary exacerbation. This bacterial strain could not be identified by our systematic MALDI-TOF mass spectrometry screening on a MicroFlex. This led to the sequencing of the 16S rRNA gene, which shows 97.83% sequence identity with Chryseobacterium kwangjuense strain KJ1R5T, the phylogenetic closely related type strain of a species with standing in nomenclature, which putatively classifies it as a new species. Colonies are yellow, circular and 0.5-1 mm in diameter after cultivation at 28 °C for 24 h on 5% sheep blood-enriched Colombia agar. Growth occurs at temperatures in the range of 28-37 °C (optimally at 28 °C). Strain 6021061333T is Gram-negative, non-motile and strictly aerobic bacillus. It is catalase and oxidase positive. The 4,864,678 bp-long genome, composed of five contigs, has a G+C content of 38.86%. Out of the 4427 predicted genes, 4342 were protein-coding genes and 85 were RNAs. The major fatty acids are branched (13-methyl-tetradecanoic acid and 15-methyl-hexadecenoic acid). Digital DNA-DNA hybridization (dDDH) estimation and average nucleotide identity (ANI) of the strain 6021061333T against genomes of the type strains of related species ranged between 23.60 and 50.40% and between 79.31 and 93.06%, respectively. According to our taxonogenomics results, we propose the creation of Chryseobacterium phocaeense sp. nov. that contains the type strain 6021061333T (= CSUR P2660, = CECT 9670).


Assuntos
Chryseobacterium/classificação , Chryseobacterium/genética , Fibrose Cística/microbiologia , Filogenia , Adolescente , Composição de Bases , Chryseobacterium/química , DNA Bacteriano/genética , Ácidos Graxos/análise , Feminino , Genoma Bacteriano/genética , Humanos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Escarro/microbiologia
9.
Arch Microbiol ; 201(3): 305-312, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604014

RESUMO

Strain 6021052837T was isolated from the blood culture of a hemodialysis patient on Chocolat PolyViteX medium at 37 °C after 2 days of incubation. Colonies could not be identified by our systematic MALDI-TOF Mass Spectrometry screening. The16S rRNA gene sequencing showed that the strain had 96% sequence identity with Cohnella formosensis (Genbank accession number JN806384), the phylogenetic closely related type strain of a species with standing in nomenclature, which putatively classifies it as a new species. The colonies cultivated on Columbia agar with 5% sheep blood medium at 37 °C after 24 h of incubation, are white pigmented, their size varied from 1.5 to 2 mm in diameter. Strain 6021052837T is an aerobic, Gram-negative, motile, spore forming rod, which cannot grow microaerophilically or under anaerobic conditions. The major fatty acids are branched saturated fatty acids: 14-methyl-pentadecanoic acid (34%) and 12-methyl-tetradecanoic acid (31%). The 6.328 Mb long genome, composed of 25 contigs, has a G+C content of 57.24%. Out of the 5710 predicted genes, 5646 were protein-coding genes and 64 were RNAs. A total of 3239 genes (57.37%) were assigned as putative function (by COGs) and 288 genes were identified as ORFans (5.1%). Average genomic identity of orthologous gene sequences (AGIOS) of strain 6021052837T against genomes of the type strains of related species ranged between 58.26 and 79.63%, respectively. According to our taxonogenomics results, we propose the creation of Cohnella massiliensis sp. nov. that contains the type strain 6021052837T (= CSUR P2659, =DSM103435).


Assuntos
Bacillales , Bacillales/classificação , Bacillales/genética , Bacillales/isolamento & purificação , Composição de Bases/genética , Hemocultura , Ácidos Graxos/análise , Genoma Bacteriano/genética , Humanos , Paenibacillus/genética , Filogenia , RNA Ribossômico 16S/genética , Diálise Renal
10.
Antonie Van Leeuwenhoek ; 112(5): 775-784, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30666529

RESUMO

Culturomics has recently allowed the isolation and description of previously uncultured bacteria from the human microbiome at different body sites. As part of a project aiming to describe the human gut microbiota by culturomics, Phoenicibacter congonensis strain Marseille-P3241T was isolated from the gut of a 45 years old Pygmy female. In the present work, we aim to describe this strain via the taxonogenomics approach. The major phenotypic, genomic and biochemical characteristics of this strain were analysed. Strain Marseille-P3241T is an anaerobic, Gram-positive and motile coccobacillus that grows optimally at 37 °C. The genome of strain Marseille-P3241T is 1,447,956 bp long with 43.44% GC content and its 16S rRNA gene sequence exhibited 89% sequence similarity with that of Denitrobacterium detoxificans strain NPOH1T, the phylogenetically closest related species with current standing in nomenclature. After performing a phylogenetic and genomic analysis, we conclude that strain Marseille-P3241T (= CCUG 70681T = CSUR P3241T) represents the type species of a new genus, for which we propose the name Phoenicibacter congonensis gen. nov., sp. nov.


Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Actinobacteria/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Fezes , Feminino , Microbioma Gastrointestinal , Humanos , Pessoa de Meia-Idade , Filogenia , RNA Ribossômico 16S/genética
11.
Antonie Van Leeuwenhoek ; 111(11): 2129-2130, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30267233

RESUMO

Subsequent to the publication of the above article, it has been noticed that the designation of the type strain is not correct. The strain referred to throughout the article as strain AT7T should be designated as strain Marseille-P2086T (= CSUR P2086T = DSM 100837T). The corrected for protologue for the species Mediterraneibacter massiliensis, represented by strain Marseille-P2086T as type strain, is given below.

12.
Antonie Van Leeuwenhoek ; 111(11): 2107-2128, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29855844

RESUMO

An anaerobic isolate, strain AT7T, was cultivated from a stool sample of a morbidly obese French woman using a microbial culturomics approach. The 16S rRNA gene sequence analysis showed that strain AT7T exhibited 96% nucleotide sequence similarity with Ruminococcus torques strain JCM 6553T (= ATCC 27756T = VPI B2-51T), currently the closest related species with a validly published name. The strain was observed to be a Gram-stain positive, non-motile, asporogenous and coccobacillary-shaped bacterium. It was found to be catalase positive and oxidase negative. Its major fatty acids were identified as C16:0 (54%) and C18:1n9 (30%). The draft genome of strain AT7T is 3,069,882 bp long with 42.4% G+C content. 2925 genes were predicted, including 2867 protein-coding genes and 58 RNAs. Based on phenotypic, biochemical, phylogenetic and genomic evidence, we propose the creation of the new genus Mediterraneibacter and species, Mediterraneibacter massiliensis, that contains strain AT7T (= CSUR P2086T = DSM 100837T), and the reclassification of Ruminococcus faecis, Ruminococcus lactaris, Ruminococcus torques, Ruminococcus gnavus, Clostridium glycyrrhizinilyticum as Mediterraneibacter faecis comb. nov., with type strain Eg2T (= KCTC 5757T = JCM15917T), Mediterraneibacter lactaris comb. nov., with type strain ATCC 29176T (= VPI X6-29T), Mediterraneibacter torques comb. nov., with type strain ATCC 27756T (= VPI B2-51T), Mediterraneibacter gnavus comb. nov., with type strain ATCC 29149T (= VPI C7-9T) and Mediterraneibacter glycyrrhizinilyticus comb. nov., with type strain ZM35T (= JCM 13368T = DSM 17593T), respectively.


Assuntos
Microbioma Gastrointestinal/genética , Ruminococcus/classificação , Ruminococcus/genética , Clostridium/classificação , Clostridium/genética , Humanos , Obesidade/microbiologia , Fenótipo , Filogenia , Análise de Sequência de DNA
13.
Curr Microbiol ; 75(4): 456-463, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29188320

RESUMO

The study of the vaginal microbiota using the "culturomics concept" allowed us to isolate, from the vaginal swab of an asymptomatic 20-year-old woman who had sexual relations with another woman with bacterial vaginosis, an unknown Gram-positive anaerobic coccus-shaped bacterium that was designated strain Marseille-P2951T and characterized using taxono-genomics. Strain Marseille-P2951T is non-motile and non-spore forming and exhibits catalase and oxidase activities. Its 16S rRNA gene-based identification showed 98.5% identity with Ezakiella peruensis, the phylogenetically closest species. The major fatty acids are C18:1n9 (58%) and C16:0 (22%). With a 1,741,785 bp length, the G+C content of the genome is 36.69%. Of a total of 1657 genes, 1606 are protein-coding genes and 51 RNAs. Also, 1123 genes are assigned a putative function and 127 are ORFans. Phenotypic, phylogenetic, and genomics analyses revealed that strain Marseille-P2951T (=CSUR P2951 =DSM 103122) is distinct and represents a new species of the genus Ezakiella, for which the name Ezakiella massiliensis sp. nov. is proposed.


Assuntos
Firmicutes/isolamento & purificação , Genoma Bacteriano , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Adulto , Técnicas de Tipagem Bacteriana , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Firmicutes/classificação , Firmicutes/genética , Firmicutes/metabolismo , Humanos , Filogenia , Adulto Jovem
14.
Curr Microbiol ; 75(10): 1274-1281, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29858619

RESUMO

A novel strain of a Gram-stain negative, non-motile, non-spore forming rod-shaped, obligate anaerobic bacterium, designated AT11T, was isolated from a stool sample of a morbidly obese woman living in Marseille, France. This bacterium was characterized using biochemical, chemotaxonomic, and phylogenetic methods. The 16S rRNA gene sequence analysis showed that strain AT11T had a 97.8% nucleotide sequence similarity with Eisenbergiella tayi strain B086562T, the closest species with standing in nomenclature. The major cellular fatty acids of the novel isolate were C16:0 followed by saturated or unsaturated C18 fatty acids (C18:1n9, C18:1n5 and C18:0). The draft genome of strain AT11T is 7,114,554 bp long with 48% G+C content. 6176 genes were predicted, including 6114 protein-coding genes and 62 were RNAs (with 2 5S rRNA genes, two 16S rRNA genes, two 23S rRNA genes, and 56 tRNA genes). The digital DNA-DNA hybridization (dDDH) relatedness between the new isolate and E. tayi strain B086562T was 23.1% ± 2.2. Based on the phenotypic, chemotaxonomic, genomic, and phylogenetic characteristics, Eisenbergiella massiliensis sp. nov., is proposed. The type strain is AT11T (= DSM 100838T = CSUR P2478T).


Assuntos
Fezes/microbiologia , Genoma Bacteriano , Obesidade Mórbida/microbiologia , Técnicas de Tipagem Bacteriana , Cirurgia Bariátrica , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , França , Microbioma Gastrointestinal , Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Filogenia , RNA Ribossômico 16S/genética
15.
Clin Infect Dis ; 65(suppl_1): S20-S29, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28859350

RESUMO

The proportion of cultured microorganisms is dramatically lower than those predicted to be involved in colonization, acute, or chronic infections. We report our laboratory's contribution to promoting culture methods. As a result of using culturomics in our clinical microbiology laboratories (including amoeba co-culture and shell-vial culture) and through the use of matrix-assisted laser desorption/ionization-time-of-flight and the 16S rRNA gene for identification, we cultured 329 new bacterial species. This is also the first time that 327 of species have been isolated from humans, increasing the known human bacterial repertoire by 29%. We isolated 4 archaeal species for the first time from human, including 2 new species. Of the 100 isolates of giant viruses, we demonstrated the human pathogenicity of Mimivirus in pneumonia and Marseillevirus in diverse clinical situations. From sand flies, we isolated most of the known Phlebovirus strains that potentially cause human infections. Increasing the repertoire of human-associated microorganisms through culture will allow us to test pathogenicity models with viable microorganisms.


Assuntos
Bactérias/isolamento & purificação , Vírus Gigantes/isolamento & purificação , Microbiota , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Técnicas de Tipagem Bacteriana , DNA Bacteriano , DNA Viral , Vírus Gigantes/classificação , Vírus Gigantes/genética , Vírus Gigantes/patogenicidade , Humanos , Microbiota/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
16.
Microb Pathog ; 106: 103-112, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27317857

RESUMO

In 1675, Antoni Van Leeuwenhoeck was the first to observe several forms using an optical microscope that he named "animalcules", realizing later that these were microorganisms. The first classification of living organisms proposed by Ehrenberg in 1833 was based on what we could visualize. The failure of this kind of classification arises from viral culture, which preceded direct observations that were finally achieved during the 20th century by electron microscopy. The number of prokaryotic species is estimated at approximately 10 million, although only 1800 were known in 1980, and 14,000 to date, thanks to the advent of 16S rRNA amplification and sequencing. This highlights our inability to access the entire diversity. Indeed, a large number of bacteria are only, known as Operational Taxonomic Units (OTUs) and detected as a result of metagenomics studies, revealing an unexplored world known as the "dark matter". Recently, the rebirth of bacterial culture through the example of culturomics has dramatically increased the human gut repertoire as well as the 18SrRNA sequencing allowed to largely extend the repertoire of Eukaryotes. Finally, filtration and co-culture on free-living protists associated with high-throughput culture elucidated a part of the megavirome. While the majority of studies currently performed on the human gut microbiota focus on bacterial diversity, it appears that several other prokaryotes (including archaea) and eukaryotic populations also inhabit this ecosystem; their detection depending exclusively on the tools used. Rational and comprehensive establishment of this ecosystem will allow the understanding of human health associated with gut microbiota and the potential to change this.


Assuntos
Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Filogenia , Animais , Archaea/classificação , Bactérias/classificação , Bactérias/genética , Biodiversidade , Técnicas de Cocultura , Fungos/classificação , Microbioma Gastrointestinal/genética , Vírus Gigantes , Ensaios de Triagem em Larga Escala/métodos , Humanos , Metagenômica , Técnicas de Tipagem Micológica/métodos , Parasitos/classificação , RNA Ribossômico 16S/genética , Análise de Sequência/métodos , Vírus/classificação
17.
Antonie Van Leeuwenhoek ; 110(9): 1121-1132, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28509971

RESUMO

Using a polyphasic taxonomic strategy, an aerobic, Gram-negative, non-motile, yellow pigmented rod isolated from a sputum sample of a patient with pneumonia was characterised. This bacterial strain, designated G972T, could not be identified by our systematic MALDI-TOF screening on a MicroFlex. This led to the sequencing of the 16S rRNA gene, which shows 98.57% sequence identity with that of Chryseobacterium indologenes 16777T, the phylogenetic closely related type strain of a species with standing in nomenclature, which putatively classifies it as a new species. The major cell fatty acids were identified as 13-methyl-tetradecanoic acid (61%), 3-hydroxy-heptadecanoic acid (16%) and 15-methyl-11-hexadecenoic acid (11%). D-glucose, D-mannose, aesculin, D-maltose, D-trehalose, and gentibiose are the main carbon source. Digital DNA-DNA hybridization (dDDH) estimation and average nucleotide identity values (ANI) of the strain G972T against genomes of the type strains of related species ranged between 18.9 and 32.8% and between 71.46 and 83.61%, respectively, thus confirming again the new species status of the strain. Here, we describe the characteristics of this organism, complete genome sequence and annotation. The 5,390,132 bp size genome contains 4867 protein-coding genes, 89 RNAs (three genes are 5S rRNA, one gene is 16S rRNA, one gene is 23S rRNA and 84 tRNAs) with 35.51% GC content. Finally, on the basis of these polyphasic data, consisting of phenotypic and genomic analyses, we conclude that strain strain G972T (= DSM 103388T = CSUR P2233T) represents a novel species for which we propose the name Chryseobacterium timonianum. The 16S rRNA and genome sequences are available in GenBank database under accession numbers LT161886 and FJVD00000000.


Assuntos
Chryseobacterium/classificação , Chryseobacterium/genética , Filogenia , Pneumonia/microbiologia , Aminoácidos/metabolismo , Composição de Bases , Chryseobacterium/química , Ácidos Graxos/química , Tamanho do Genoma , Genoma Bacteriano , Humanos , Fenótipo , RNA Ribossômico 16S/genética , Especificidade da Espécie , Escarro/microbiologia , Açúcares/metabolismo
18.
Microb Ecol ; 71(4): 990-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26714966

RESUMO

Strain G4(T) was isolated from the stool sample of a wild gorilla (Gorilla gorilla gorilla) from Cameroon. It is a facultative anaerobic, Gram-negative, rod-shaped bacterium. This strain exhibits a 16S rRNA nucleotide sequence similarity of 97.48% with Paenibacillus typhae, the phylogenetically closest species with standing nomenclature. Moreover, the strain G4(T) presents some phenotypic differences when compared to other Paenibacillus species and shows a low MALDI-TOF Mass Spectrometry score that does not allow any identification. Thus, it is likely that this strain represents a new species. Here, we describe the characteristics of this organism, complete genome sequence, and annotation. The 6,933,847 bp size genome (1 chromosome but no plasmid) contains 5972 protein-coding genes and 54 RNAs genes, including 44 tRNA genes. In addition, digital DNA-DNA hybridization values for the genome of the strain G4(T) against the closest Paenibacillus genomes range between 19.7 and 22.1, once again confirming its new status as a new species. On the basis of these polyphasic data, consisting of phenotypic and genomic analyses, we propose the creation of Paenibacillus camerounensis sp. nov. that contains the strain G4(T).


Assuntos
Paenibacillus/genética , Animais , Proteínas de Bactérias/genética , Sequência de Bases , Camarões , Mapeamento Cromossômico , DNA Bacteriano/genética , DNA Ribossômico/genética , Genes de RNAr , Gorilla gorilla/microbiologia , Paenibacillus/química , Paenibacillus/isolamento & purificação , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , RNA de Transferência/genética , Análise de Sequência de DNA , Especificidade da Espécie
19.
Anaerobe ; 40: 85-94, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27328611

RESUMO

Anaerococcus rubiinfantis sp. nov. strain mt16(T) is a new species within the genus Anaerococcus, which was isolated by the culturomics approach from the gut microbiota of an infant suffering from kwashiorkor. A phenotypic, biochemical and proteomic description of this strain is hereby presented alongside a complete annotation of its genome. This strictly anaerobic species forms Gram-positive non-sporeforming cocci. The major fatty acid was hexadecanoic acid. The phylogenetic analysis of strain mt16(T) showed a 97.9% similarity level with Anaerococcus vaginalis, the closest validly published species. Its genome is 1,929,161 bp long with 29.5% G + C content and contains 1808 protein-coding genes and 56 RNA genes, among which are six rRNA genes. Genomic analysis identified 41/1864 coding genes as ORFans (2.2%) and at least 620/1808 (34.9%) orthologous proteins which are not shared with the closest phylogenetic species. We believe that the extension of the human anaerobic gut compendium by culturomics is one of the first steps that will improve the understanding of the links between the microbiome and health or disease.


Assuntos
Firmicutes/genética , Genes Bacterianos , Genoma Bacteriano , Bactérias Gram-Positivas/genética , Filogenia , Anaerobiose , Composição de Bases , Firmicutes/classificação , Firmicutes/isolamento & purificação , Microbioma Gastrointestinal/genética , Ontologia Genética , Tamanho do Genoma , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Lactente , Kwashiorkor/microbiologia , Kwashiorkor/patologia , Anotação de Sequência Molecular , Fases de Leitura Aberta , Ácido Palmítico/isolamento & purificação , Ácido Palmítico/metabolismo
20.
J Infect Dis ; 211(2): 267-73, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25001460

RESUMO

Vector-borne parasites of the genus Leishmania are responsible for severe human diseases. Cutaneous leishmaniasis, a common form of the disease, is most often caused by the transmission of Leishmania major to humans by female phlebotomine sand flies. Apes are increasingly being seen as a source of zoonotic diseases, including malaria and rickettsiosis. To examine whether gorillas harbor Leishmania species, we screened fecal samples from wild western lowland gorillas (Gorilla gorilla gorilla) in Cameroon for the presence of these pathogens. Of 91 wild gorilla fecal samples, 12 contained Leishmania parasites, and 4 contained phlebotomine sand fly vectors. The molecular identity was determined by running 3 different polymerase chain reaction tests for detection of L. major. Next, fluorescence in situ hybridization was performed to visualize L. major parasites in fecal samples from the gorillas. Both promastigote and amastigote forms of the parasite were found. This work strongly suggests that wild gorillas carry pathogenic Leishmania parasites.


Assuntos
Reservatórios de Doenças , Fezes/parasitologia , Gorilla gorilla/parasitologia , Leishmania major/isolamento & purificação , Animais , DNA de Protozoário/genética , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase
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