F. Cadoret

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).

Gene transfer: transformation/electroporation.

Since Pseudomonas aeruginosa is a non-naturally competent bacterium, various methods have been developed to transfer exogenous DNA. Alternatively to transduction and conjugation, electroporation can also be used to transfer exogenous DNA molecules into Pseudomonas. Electroporation uses an electric field which generates pores in bacterial membranes allowing the entry of the exogenous DNA molecule. In contrast to conjugation which is restricted to the transfer of DNA from one bacterial cell to another, electroporation can be used to transfer all types of DNA resuspended in water.

“Libanicoccus massiliensis” gen. nov., sp. nov., a new bacterium isolated from a stool sample from a pygmy woman

This study supports the main characteristics of a new genus “Libanicoccus massiliensis” strain Marseille-P3237 (CSURP3237); a new member of the order Coribacteriaceae that was isolated from a stool sample from a healthy 35-year-old pygmy woman.

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 ‘Gorbachella massiliensis’ gen. nov., sp. nov., ‘Fenollaria timonensis’ sp. nov., ‘Intestinimonas timonensis’ sp. nov. and ‘Collinsella ihuae’ sp. nov. isolated from healthy fresh stools with culturomics

We report here the main characteristics of ‘Gorbachella massiliensis’ GD7T gen. nov., sp. nov., ‘Fenollaria timonensis’ GD5T sp. nov., ‘Intestinimonas timonensis’ GD4T sp. nov., and ‘Collinsella ihuae’ sp. nov. GD8T isolated from one fresh stool of a French volunteer. We used a bacterial culturomics approach combined with taxono-genomics.

‘Urmitella timonensis’ gen. nov., sp. nov., ‘Blautia marasmi’ sp. nov., ‘Lachnoclostridium pacaense’ sp. nov., ‘Bacillus marasmi’ sp. nov. and ‘Anaerotruncus rubiinfantis’ sp. nov., isolated from stool samples of undernourished African children

We report here the main characteristics of five new species ‘Urmitella timonensis’ strain Marseille-P2918T (CSUR P2918), ‘Blautia marasmi’ strain Marseille-P2377T (CSUR P2377), ‘Lachnoclostridium pacaense’ strain Marseille-P3100T (CSUR P3100), ‘Bacillus marasmi’ strain Marseille-P3556T (CSUR P3556) and ‘Anaerotruncus rubiinfantis’ strain MT15T (CSUR P2276), which were isolated recently from stool samples taken from undernourished children in Niger and Senegal using microbial culturomics.

‘Khelaifiella massiliensis’, ‘Niameybacter massiliensis’, ‘Brachybacterium massiliense’, ‘Enterobacter timonensis’, ‘Massilibacillus massiliensis’, new bacterial species and genera isolated from the gut microbiota of healthy infants

The main characteristics of ‘Khelaifiella massiliensis’ strain Mt13T (= CSUR P1935, = DSM100591), ‘Niameybacter massiliensis’ strain Mt14T (= CSUR P1909, = DSM100592), ‘Brachybacterium massiliense’ strain MT5T (= CSUR P2240, = DSM101766), ‘Enterobacter timonensis’ strain mt20T (= CSUR P2201, = DSM 101775) and ‘Massilibacillus massiliensis’ strain Marseille-P2411T (= CSUR P2411, = DSM102838), new species isolated from the gut of healthy African infants, are presented.

‘Collinsella phocaeensis’ sp. nov., ‘Clostridium merdae’ sp. nov., ‘Sutterella massiliensis’ sp. nov., ‘Sutturella timonensis’ sp. nov., ‘Enorma phocaeensis’ sp. nov., ‘Mailhella massiliensis’ gen. nov., sp. nov., ‘Mordavella massiliensis’ gen. nov., sp. nov. and ‘Massiliprevotella massiliensis’ gen. nov., sp. nov., 9 new species isolated from fresh stool samples of healthy French patients

Here we report of summary of the characteristics of ‘Collinsella phocaeensis’ strain Marseille-P3245T sp. nov., ‘Clostridium merdae’ strain Marseille-P2953T, ‘Sutterella massiliensis’ strain Marseille-P2435T sp. nov., ‘Sutturella timonensis’ strain Marseille-P3282T sp. nov., ‘Enorma phocaeensis’ Marseille-P3242T sp. nov., ‘Mailhella massiliensis’ strain Marseille-P3199T gen. nov., sp. nov., ‘Mordavella massiliensis’ strain Marseille-P3246T sp. nov. and ‘Massiliprevotella massiliensis’ strain Marseille-P2439T sp. nov. isolated from fresh stool samples of healthy French patients.

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.

Libanicoccus massiliensis gen. nov., sp. nov., a new bacterium isolated from human stool

Strain Marseille-P3237 was isolated from a stool sample of a healthy 35-year-old Congolese pygmy female. This anaerobic, Gram-negative, non-spore-forming and non-motile coccus-shaped bacterium is a member of the order Coriobacteriales. It exhibits a 2 009 306-bp genome with a 65.46 mol% G+C content and is closely related to, but distinct from, members of the Olsenella genus. We propose the creation of the new genus Libanicoccus gen. nov. and of the new species Libanicoccus massiliensis sp. nov.