Vaginimicrobium propionicum gen. nov., sp. nov., a novel propionic acid bacterium derived from human vaginal discharge.

A Gram-stain-positive anaerobic rod-shaped bacterium, designated strain Marseille-P3275T, was isolated using culturomics from the vaginal discharge of healthy French woman. Marseille-P3275T was non-motile and did not form spores. Cells had neither catalase nor oxidase activity. The major fatty acids were C16 : 0 (29 %), C18:1ω9 (18 %), and iso-C15 : 0 (17 %). The genomic DNA G+C content was 50.64 mol%. The phylogenetic analysis based on 16S rRNA gene sequence indicated that Marseille-P3275T was related to members of the family Propionibacteriaceae (between 90.32-92.92 % sequence similarity) with formation of a clade with the monospecific genus Propionimicrobium (type species Propionimicrobium lymphophilum). On the basis of these phylogenetic and phenotypic differences, Marseille-P3275T was classified in a novel genus, Vaginimicrobium, as Vaginimicrobium propionicum gen. nov., sp. nov. The type strain is Marseille-P3275T (=CSUR P3275T=CECT 9677T).

Direct interactions between the secreted effector and the T2SS components GspL and GspM reveal a new effector-sensing step during type 2 secretion.

In many Gram-negative bacteria, the type 2 secretion system (T2SS) plays an important role in virulence because of its capacity to deliver a large amount of fully folded protein effectors to the extracellular milieu. Despite our knowledge of most T2SS components, the mechanisms underlying effector recruitment and secretion by the T2SS remain enigmatic. Using complementary biophysical and biochemical approaches, we identified here two direct interactions between the secreted effector CbpD and two components, XcpYL and XcpZM, of the T2SS assembly platform (AP) in the opportunistic pathogen Pseudomonas aeruginosa Competition experiments indicated that CbpD binding to XcpYL is XcpZM-dependent, suggesting sequential recruitment of the effector by the periplasmic domains of these AP components. Using a bacterial two-hybrid system, we then tested the influence of the effector on the AP protein-protein interaction network. Our findings revealed that the presence of the effector modifies the AP interactome and, in particular, induces XcpZM homodimerization and increases the affinity between XcpYL and XcpZM The observed direct relationship between effector binding and T2SS dynamics suggests an additional synchronizing step during the type 2 secretion process, where the activation of the AP of the T2SS nanomachine is triggered by effector binding.

Phoenicibacter congonensis gen. nov., sp. nov., a new genus isolated from the human gut and its description using a taxonogenomic approach.

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.

Dysgonomonas massiliensis sp. nov., a new species isolated from the human gut and its taxonogenomic description.

Culturomics has allowed the isolation of a significant number of new bacterial species from the human gut microbiota and proved to be a valuable complement to culture-independent techniques. Using this culture-based approach, a new bacterial species has been isolated from a stool sample of a 39-year-old healthy Pygmy male and described using the taxonogenomic strategy. Cells of strain Marseille-P4356T are Gram-stain negative cocci. The strain grows optimally at 37 °C and is catalase positive but oxidase negative. Its 16S rRNA gene sequence exhibited 92.96% sequence similarity with Dysgonomonas gadei strain JCM 16698T (NR_113134.1), currently its phylogenetically closest species that has been validly named. The genome of strain Marseille-P4356T is 3,472,011 bp long with 37.3 mol% G+C content. Phenotypic, biochemical, proteomic, genomic and phylogenetic analyses, clearly demonstrate that strain Marseille-P4356T (= CCUG 71356T = CSUR P4356T) represents a new species within the genus Dysgonomonas, for which we propose the name Dysgonomonas massiliensis sp. nov.

From Culturomics to Clinical Microbiology and Forward.

Culturomics has permitted discovery of hundreds of new bacterial species isolated from the human microbiome. Profiles generated by using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry have been added to the mass spectrometer database used in clinical microbiology laboratories. We retrospectively collected raw data from MALDI-TOF mass spectrometry used routinely in our laboratory in Marseille, France, during January 2012-March 2018 and analyzed 16S rDNA sequencing results from misidentified strains. During the study period, 744 species were identified from clinical specimens, of which 21 were species first isolated from culturomics. This collection involved 105 clinical specimens, accounting for 98 patients. In 64 cases, isolation of the bacteria was considered clinically relevant. MALDI-TOF mass spectrometry was able to identify the species in 95.2% of the 105 specimens. While contributing to the extension of the bacterial repertoire associated with humans, culturomics studies also enlarge the spectrum of prokaryotes involved in infectious diseases.

Repertoire of the gut microbiota from stomach to colon using culturomics and next-generation sequencing.

BACKGROUND: Most studies on the human microbiota have analyzed stool samples, although a large proportion of the absorption of nutrients takes place in upper gut tract. We collected samples from different locations along the entire gastrointestinal tract from six patients who had simultaneously undergone upper endoscopy and colonoscopy, to perform a comprehensive analysis using culturomics with matrix assisted laser desorption ionisation - time of flight (MALDI-TOF) identification and by metagenomics targeting the 16S ribosomal ribonucleic acid (rRNA) gene. RESULTS: Using culturomics, we isolated 368 different bacterial species, including 37 new species. Fewer species were isolated in the upper gut: 110 in the stomach and 106 in the duodenum, while 235 were isolated from the left colon (p < 0.02). We isolated fewer aero-intolerant species in the upper gut: 37 from the stomach and 150 from the left colon (p < 0.004). Using metagenomics, 1,021 species were identified. The upper gut microbiota was revealed to be less rich than the lower gut microbiota, with 37,622 reads from the stomach, 28,390 from the duodenum, and 79,047 from the left colon (p < 0.009). There were fewer reads for aero-intolerant species in the upper gut (8,656 in the stomach, 5,188 in the duodenum and 72,262 in the left colon, p < 0.02). Patients taking proton pump inhibitors (PPI) were then revealed to have a higher stomach pH and a greater diversity of species in the upper digestive tract than patients not receiving treatment (p < 0.001). CONCLUSION: Significant modifications in bacterial composition and diversity exist throughout the gastrointestinal tract. We suggest that the upper gut may be key to understanding the relationship between the gut microbiota and health.

Anaerococcus jeddahensis sp. nov., a New Bacterial Species Isolated From Healthy Nomadic Bedouin Woman From Saudi Arabia.

An understanding of the microbial diversity of the human body has generated significant interest in recent years. With the advent of MALDI-TOF mass spectrometry, high-speed sequencing, and the rebirth of microbial culture, knowledge of human microbiota is growing. Using culturomics, a strategy to explore the microbial diversity of samples, coupled with a taxono-genomic strategy, we isolated a new bacterium named Anaerococcus jeddahensis sp. nov. strain SB3T. This strain was isolated from the stool sample of a healthy nomadic Bedouin woman from Saudi Arabia. Here, we describe the characteristics of this organism, and the complete genome sequence and annotation. Strain SB3T is a Gram-positive obligate anaerobic coccus which is non-motile and non-spore forming. Fatty acid analysis shows that the major fatty acid is by far hexadecanoic acid (C16:0; 52%). Its genome is 1,903,534 bp long and has 29.70 mol% of G+C content. It contains 1756 protein-coding genes and 53 RNA genes. These results show that strategy provides a better understanding of the microorganism and that is a good methodology for microbial identification and characterization.

Fournierella massiliensis gen. nov., sp. nov., a new human-associated member of the family Ruminococcaceae.

An anaerobic bacterium, strain AT2T, was isolated from the fresh stool sample of a healthy French man using the culturomics approach. The 16S rRNA gene sequence analysis showed that strain AT2T had 95.2 % nucleotide sequence similarity with Gemmiger formicilisATCC 27749T, the phylogenetically closest species with standing in nomenclature. Cells are Gram-stain-negative, catalase- and oxidase-negative, obligately anaerobic, non-motile, non-spore-forming, rod-shaped, and the bacilli were mesothermophilic. The major fatty acids were C16 : 0 (43.8 %) and C18 : 1n9 (20 %). The DNA G+C content of the strain based on its genome sequence was 56.8 mol%. Based on the phenotypic, biochemical and phylogenetic analysis, we propose the creation of the genus Fournierella gen. nov., which contains strain AT2T (=CSUR P2014T=DSM 100451T) as the type strain of the type species Fournierella massiliensis gen. nov., sp. nov.

Description of Chryseobacterium timonianum sp. nov., isolated from a patient with pneumonia.

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.

Olegusella massiliensis gen. nov., sp. nov., strain KHD7T, a new bacterial genus isolated from the female genital tract of a patient with bacterial vaginosis.

Strain KHD7T, a Gram-stain-positive rod-shaped, non-sporulating, strictly anaerobic bacterium, was isolated from the vaginal swab of a woman with bacterial vaginosis. We studied its phenotypic characteristics and sequenced its complete genome. The major fatty acids were C16:0 (44%), C18:2n6 (22%), and C18:1n9 (14%). The 1,806,744 bp long genome exhibited 49.24% G+C content; 1549 protein-coding and 51 RNA genes. Strain KHD7T exhibited a 93.5% 16S rRNA similarity with Olsenella uli, the phylogenetically closest species in the family Coriobacteriaceae. Therefore, strain KHD7T is sufficiently distinct to represent a new genus, for which we propose the name Olegusella massiliensis gen. nov., sp. nov. The type strain is KHD7T.

Dichlorotrifluoromethoxyacetic Acid: Preparation and Reactivity.

We describe the first gram scale preparation of the reagent dichlorotrifluoromethoxyacetic acid. This stable compound is obtained in five steps starting from the cheap diethylene glycol. The reactivity of the sodium salt of this fluorinated acid was also tested and allowed the preparation of new amides.

Txc, a new type II secretion system of Pseudomonas aeruginosa strain PA7, is regulated by the TtsS/TtsR two-component system and directs specific secretion of the CbpE chitin-binding protein.

We present here the functional characterization of a third complete type II secretion system (T2SS) found in newly sequenced Pseudomonas aeruginosa strain PA7. We call this system Txc (third Xcp homolog). This system is encoded by the RGP69 region of genome plasticity found uniquely in strain PA7. In addition to the 11 txc genes, RGP69 contains two additional genes encoding a possible T2SS substrate and a predicted unorthodox sensor protein, TtsS (type II secretion sensor). We also identified a gene encoding a two-component response regulator called TtsR (type II secretion regulator), which is located upstream of the ttsS gene and just outside RGP69. We show that TtsS and TtsR constitute a new and functional two-component system that controls the production and secretion of the RGP69-encoded T2SS substrate in a Txc-dependent manner. Finally, we demonstrate that this Txc-secreted substrate binds chitin, and we therefore name it CbpE (chitin-binding protein E).

A New Phenolic Acid Decarboxylase from the Brown-Rot Fungus Neolentinus lepideus Natively Decarboxylates Biosourced Sinapic Acid into Canolol, a Bioactive Phenolic Compound.

Rapeseed meal (RSM) is a cheap, abundant and renewable feedstock, whose biorefinery is a current challenge for the sustainability of the oilseed sector. RSM is rich in sinapic acid (SA), a p-hydroxycinnamic acid that can be decarboxylated into canolol (2,6-dimethoxy-4-vinylphenol), a valuable bioactive compound. Microbial phenolic acid decarboxylases (PADs), mainly described for the non-oxidative decarboxylation of ferulic and p-coumaric acids, remain very poorly documented to date, for SA decarboxylation. The species Neolentinus lepideus has previously been shown to biotransform SA into canolol in vivo, but the enzyme responsible for bioconversion of the acid has never been characterized. In this study, we purified and characterized a new PAD from the canolol-overproducing strain N. lepideus BRFM15. Proteomic analysis highlighted a sole PAD-type protein sequence in the intracellular proteome of the strain. The native enzyme (NlePAD) displayed an unusual outstanding activity for decarboxylating SA (Vmax of 600 U.mg-1, kcat of 6.3 s-1 and kcat/KM of 1.6 s-1.mM-1). We showed that NlePAD (a homodimer of 2 × 22 kDa) is fully active in a pH range of 5.5-7.5 and a temperature range of 30-55 °C, with optima of pH 6-6.5 and 37-45 °C, and is highly stable at 4 °C and pH 6-8. Relative ratios of specific activities on ferulic, sinapic, p-coumaric and caffeic acids, respectively, were 100:24.9:13.4:3.9. The enzyme demonstrated in vitro effectiveness as a biocatalyst for the synthesis of canolol in aqueous medium from commercial SA, with a molar yield of 92%. Then, we developed processes to biotransform naturally-occurring SA from RSM into canolol by combining the complementary potentialities of an Aspergillus niger feruloyl esterase type-A, which is able to release free SA from the raw meal by hydrolyzing its conjugated forms, and NlePAD, in aqueous medium and mild conditions. NlePAD decarboxylation of biobased SA led to an overall yield of 1.6-3.8 mg canolol per gram of initial meal. Besides being the first characterization of a fungal PAD able to decarboxylate SA, this report shows that NlePAD is very promising as new biotechnological tool to generate biobased vinylphenols of industrial interest (especially canolol) as valuable platform chemicals for health, nutrition, cosmetics and green chemistry.

Synthesis of the stereogenic triad of the halicyclamine A core.

We describe herein our progress toward the synthesis of halicyclamine A, which possesses very interesting biological activities and has never been synthesized. For this purpose, we proposed a stereoselective Diels-Alder reaction as a key step for the establishment of the stereogenic triad of the bis(piperidinyl) core of this molecule. A series of NMR studies was then conducted to establish the correct stereochemical assignment subsequent to the Diels-Alder reaction.

Noncontiguous finished genome sequence and description of Intestinimonas massiliensis sp. nov strain GD2T , the second Intestinimonas species cultured from the human gut.

Intestinimonas massiliensis sp. nov strain GD2T is a new species of the genus Intestinimonas (the second, following Intestinimonas butyriciproducens gen. nov., sp. nov). First isolated from the gut microbiota of a healthy subject of French origin using a culturomics approach combined with taxono-genomics, it is strictly anaerobic, nonspore-forming, rod-shaped, with catalase- and oxidase-negative reactions. Its growth was observed after preincubation in an anaerobic blood culture enriched with sheep blood (5%) and rumen fluid (5%), incubated at 37°C. Its phenotypic and genotypic descriptions are presented in this paper with a full annotation of its genome sequence. This genome consists of 3,104,261 bp in length and contains 3,074 predicted genes, including 3,012 protein-coding genes and 62 RNA-coding genes. Strain GD2T significantly produces butyrate and is frequently found among available 16S rRNA gene amplicon datasets, which leads consideration of Intestinimonas massiliensis as an important human gut commensal.

Miniphocibacter massiliensis gen. nov., sp. nov., a new species isolated from the human gut and its taxono-genomics description.

With the aim of describing the human microbiota by the means of culture methods, culturomics was developed in order to target previously un-isolated bacterial species and describe it via the taxono-genomics approach. While performing a descriptive study of the human gut microbiota of the pygmy people, strain Marseille-P4678T has been isolated from a stool sample of a healthy 39-year-old pygmy male. Cells of this strain were Gram-positive cocci, spore-forming, non-motile, catalase-positive and oxidase-negative, and grow optimally at 37°C under anaerobic conditions. Its 16S rRNA gene sequence exhibited 89.69% of sequence similarity with Parvimonas micra strain 3119BT (NR 036934.1), its phylogenetically closest species with standing in nomenclature. The genome of strain Marseille-P4678T is 2,083,161 long with 28.26 mol% of G+C content. Based on its phenotypic, biochemical, genotypic and proteomic profile, this bacterium was classified as a new bacterial genus and species Miniphocibacter massiliensis gen. nov., sp. nov. with the type strain Marseille-P4678T .

Taxonogenomics description of Parabacteroides timonensis sp. nov. isolated from a human stool sample.

Intensive efforts have been made to describe the human microbiome and its involvement in health and disease. Culturomics has been recently adapted to target formerly uncultured bacteria and other unclassified bacterial species. This approach enabled us to isolate in the current study a new bacterial species, Parabacteroides timonensis strain Marseille-P3236T , from a stool sample of a healthy 39-year-old pygmy male. This strain, is an anaerobic, gram-negative, nonspore-forming motile rod. Its genome is made up of 6,483,434 bp with 43.41% G+C content, 5046 protein-encoding genes, and 84 RNA genes. We herein provide the full description of Parabacteroides timonensis strain Marseille-P3236T through the taxonogenomic approach.

Extensive culturomics of 8 healthy samples enhances metagenomics efficiency.

Molecular approaches have long led to the assumption that the human gut microbiota is dominated by uncultivable bacteria. The recent advent of large-scale culturing methods, and in particular that of culturomics have demonstrated that these prokaryotes can in fact be cultured. This is increasing in a dramatic manner the repertoire of commensal microbes inhabiting the human gut. Following eight years of culturomics approach applied on more than 900 samples, we propose herein a remake of the pioneering study applying a dual approach including culturomics and metagenomics on a cohort of 8 healthy specimen. Here we show that culturomics enable a 20% higher richness when compared to molecular approaches by culturing 1 archaeal species and 494 bacterial species of which 19 were new taxa. Species discovered as a part of previous culturomics studies represent 30% of the cultivated isolates, while sequences derived from these new taxa enabled to increase by 22% the bacterial richness retrieved by metagenomics. Overall, 67% of the total reads generated were covered by cultured isolates, significantly reducing the hidden content of sequencing methods compared to the pioneering study. By redefining culture conditions to recover microbes previously considered fastidious, there are greater opportunities than ever to eradicate metagenomics dark matter.