The commensal bacterium Faecalibacterium prausnitzii has unique anti-inflammatory properties, at least some of which have been attributed to its production of MAM, the Microbial Anti-inflammatory Molecule. Previous phylogenetic studies of F. prausnitzii strains have revealed the existence of various phylogroups. In this work, we address the question of whether MAMs from different phylogroups display distinct anti-inflammatory properties. We first performed wide-scale identification, classification, and phylogenetic analysis of MAM-like proteins encoded in different genomes of F. prausnitzii. When combined with a gene context analysis, this approach distinguished at least 10 distinct clusters of MAMs, providing evidence for functional diversity within this protein. We then selected 11 MAMs from various clusters and evaluated their anti-inflammatory capacities in vitro. A wide range of anti-inflammatory activity was detected. MAM from the M21/2 strain had the highest inhibitory effect (96% inhibition), while MAM from reference strain A2-165 demonstrated only 56% inhibition, and MAM from strain CNCM4541 was almost inactive. These results were confirmed in vivo in murine models of acute and chronic colitis. This study provides insights into the family of MAM proteins and generates clues regarding the choice of F. prausnitzii strains as probiotics for use in targeting chronic inflammatory diseases.

The evolution of Next-Generation Sequencing (NGS) has considerably reduced the cost per sequenced-base, allowing a significant rise of sequencing projects, mainly in prokaryotes. However, the range of available NGS platforms requires different strategies and software to correctly assemble genomes. Different strategies are necessary to properly complete an assembly project, in addition to the installation or modification of various software. This requires users to have significant expertise in these software and command line scripting experience on Unix platforms, besides possessing the basic expertise on methodologies and techniques for genome assembly. These difficulties often delay the complete genome assembly projects. In order to overcome this, we developed SIMBA (SImple Manager for Bacterial Assemblies), a freely available web tool that integrates several component tools for assembling and finishing bacterial genomes. SIMBA provides a friendly and intuitive user interface so bioinformaticians, even with low computational expertise, can work under a centralized administrative control system of assemblies managed by the assembly center head. SIMBA guides the users to execute assembly process through simple and interactive pages. SIMBA workflow was divided in three modules: (i) projects: allows a general vision of genome sequencing projects, in addition to data quality analysis and data format conversions; (ii) assemblies: allows de novo assemblies with the software Mira, Minia, Newbler and SPAdes, also assembly quality validations using QUAST software; and (iii) curation: presents methods to finishing assemblies through tools for scaffolding contigs and close gaps. We also presented a case study that validated the efficacy of SIMBA to manage bacterial assemblies projects sequenced using Ion Torrent PGM. Besides to be a web tool for genome assembly, SIMBA is a complete genome assemblies project management system, which can be useful for managing of several projects in laboratories. SIMBA source code is available to download and install in local webservers at http://ufmg-simba.sourceforge.net .

Pertussis is a highly contagious respiratory disease caused by Bordetella pertussis, a Gram-negative bacterium described over a century ago. Despite broad vaccine coverage and treatment options, the disease is remerging as a public health problem especially in infants and older children. Recent data indicate re-emergence of the disease is related to bacterial resistance to immune defences and decreased vaccine effectiveness, which obviously suggests the need of new effective vaccines and drugs. In an attempt to contribute with solutions to this great challenge, bioinformatics tools were used to genetically comprehend the species of these bacteria and predict new vaccines and drug targets. In fact, approaches were used to analysis genomic plasticity, gene synteny and species similarities between the 20 genomes of Bordetella pertussis already available. Furthermore, it was conducted reverse vaccinology and docking analysis to identify proteins with potential to become vaccine and drug targets, respectively. The analyses showed the 20 genomes belongs to a homogeneous group that has preserved most of the genes over time. Besides that, were found genomics islands and good proteins to be candidates for vaccine and drugs. Taken together, these results suggests new possibilities that may be useful to develop new vaccines and drugs that will help the prevention and treatment strategies of pertussis disease caused by these Bordetella strains. Communicated by Ramaswamy H. Sarma

Apolipoprotein E (apo E) is a human glycoprotein with 299 amino acids, and it is a major component of very low density lipoproteins (VLDL) and a group of high-density lipoproteins (HDL). Phylogenetic studies are important to clarify how various apo E proteins are related in groups of organisms and whether they evolved from a common ancestor. Here, we aimed at performing a phylogenetic study on apo E carrying organisms. We employed a classical and robust method, such as Maximum Likelihood (ML), and compared the results using a more recent approach based on complex networks. Thirty-two apo E amino acid sequences were downloaded from NCBI. A clear separation could be observed among three major groups: mammals, fish and amphibians. The results obtained from ML method, as well as from the constructed networks showed two different groups: one with mammals only (C1) and another with fish (C2), and a single node with the single sequence available for an amphibian. The accordance in results from the different methods shows that the complex networks approach is effective in phylogenetic studies. Furthermore, our results revealed the conservation of apo E among animal groups.

The genus Rickettsia belongs to the Proteobacteria phylum and these bacteria infect animals and humans causing a range of diseases worldwide. The genus is divided into 4 groups and despite the public health threat and the knowledge accumulated so far, the mandatory intracellular bacteria behaviour and limitation for in vitro culture makes it difficult to create new vaccines and drug targets to these bacteria. In an attempt to overcome these limitations, pan-genomic approaches has used 47 genomes of the genus Rickettsia, in order to describe species similarities and genomics islands. Moreover, we conducted reverse vaccinology and docking analysis aiming the identification of proteins that have great potential to become vaccine and drug targets. We found out that the bacteria of the four Rickettsia groups have a high similarity with each other, with about 90 to 100% of identity. A pathogenicity island and a resistance island were predicted. In addition, 8 proteins were also predicted as strong candidates for vaccine and 9 as candidates for drug targets. The prediction of the proteins leads us to believe in a possibility of prospecting potential drugs or creating a polyvalent vaccine, which could reach most strains of this large group of bacteria. Communicated by Ramaswamy H. Sarma

Génomique comparative de faecalibacterium spp.: Dans le côlon humain, le genre Faecalibacterium est le membre principal du groupe Clostridium leptum et comprend le deuxième genre représentatif le plus commun dans les échantillons fécaux, après Clostridium coccoides. Il a été reconnu comme une bactérie importante favorisant la santé intestinale et est aujourd'hui considéré comme un probiotique de prochaine génération. Jusqu'à récemment, on croyait qu'il n'y avait qu'une seule espèce dans ce genre, mais depuis 2012, certaines études ont commencé à suggérer l'existence de deux phylogroupes dans le genre. Cette nouvelle proposition de reclassification dans ce genre augmente l'importance de nouvelles études, toutes souches confondues, pour mieux comprendre la diversité, les interactions avec l'hôte et les aspects sécuritaires dans son utilisation comme probiotique. Brièvement, dans ce travail, nous introduisons les analyses de génomique comparative au genre Faecalibacterium en effectuant une étude phylogénétique profonde et en évaluant les aspects de sécurité pour son utilisation comme probiotique. Les analyses phylogénétiques comprenaient non seulement l'utilisation classique du gène de l'ARNr 16S, mais aussi l'utilisation de 17 génomes et techniques complets comme le typage de séquence multi-locus (wgMLST), l'identité nucléotidique moyenne (ANI), le synténie génique et le pangénome. C'est aussi le premier travail à combiner une analyse du développement du pangénome avec l'analyse ANI afin de corroborer l'attribution de souches à de nouvelles espèces. Les analyses phylogénétiques ont confirmé l'existence de plus d'une espèce dans le genre Faecalibacterium. De plus, l'évaluation de la sécurité impliquait (1) la prédiction des régions acquises horizontalement (îlots de résistance aux antibiotiques, îlots métaboliques et régions phagiques), (2) la prédiction des voies métaboliques, (3) la recherche de gènes liés à la résistance aux antibiotiques et des bactériocines. Ces analyses ont identifié des îlots génomiques dans tous les génomes, mais aucun d'entre eux n'est exclusif à une souche ou à une génospécie. En outre, ont été identifiés 8 gènes liés aux mécanismes de résistance aux antibiotiques répartis entre les génomes. 126 voies métaboliques ont été prédites et parmi certaines ont été mises en évidence: la dégradation du bisphénol A, le métabolisme du butanoate et la biosynthèse de la streptomycine. En outre, nous avons étudié le contexte génomique d'une protéine (molécule anti-inflammatoire microbienne - MAM) décrite pour la première fois par notre groupe. Cette recherche montre que la MAM apparaît proche des gènes liés au processus de sporulation et, dans certaines souches, proche d'un transporteur ABC.