Scarce information exists about the role of lung antigen-presenting cells (APCs) in vivo during pulmonary tuberculosis. As APCs activate cellular immunity, following intratracheal inoculation with virulent Mycobacterium tuberculosis, we assessed in situ lung APC recruitment, distribution, granuloma involvement, morphology and mycobacterial burden by using MHC-CII, CD14, scavenger receptor class A (SRA), the murine dendritic cell (DC)-restricted marker CD11c and Ziehl-Neelsen staining. CD11c(+) DC and CD14(+) cell recruitment into lungs appeared by day 14, continuing until day 60. MHC-CII(+) cells increased since day 7, persisting until day 60. Thus, virulent mycobacteria delays (14-21 days) lung APC recruitment compared to model antigens and nonvirulent bacilli (24-48 h). Regarding granuloma constitution, highly bacillary CD14(+) and SRA(+) cells were centrally located. MHC-CII(+) cells were more peripheral, with less mycobacteria. CD11c(+) cells were heterogeneously distributed within granulomas, with scarce bacilli. When labelling lung suspensions for MHC-CII and classifying cells as macrophages or DC, then staining for Ziehl-Neelsen, a remarkable segregation was found regarding bacillary burden. Most macrophage-like cells contained numerous bacilli, while DC had no or scarce mycobacteria. This implies differential APC contributions in situ during pulmonary tuberculosis regarding mycobacterial uptake, granuloma involvement and perhaps bacillary growth.

Open access to sequence data is a cornerstone of biology and biodiversity research, but has created tension under the United Nations Convention on Biological Diversity (CBD). Policy decisions could compromise research and development, unless a practical multilateral solution is implemented.Here, we lay out a framework for use of digital sequence information (DSI) that enables fair benefit-sharing, ensures open access to sequence data, strengthens biodiversity conservation and sustainable use, and leverages genomics and bioinformatics for international capacity-building. As Parties to the CBD meet again in-person in the coming months to negotiate the Global Biodiversity Framework, they must apply pragmatic, multilateral solutions to DSI that improve rather than impede global biodiversity targets.The ability to decode and digitally archive DNA has revolutionized the life sciences and related fields. Sequence data, referred to as digital sequence information (DSI) in policy

Mycobacterium tuberculosis has the remarkable capacity to survive within the hostile environment of the macrophage, and to resist potent antibacterial molecules such as reactive oxygen species (ROS). Thus, understanding mycobacterial resistance mechanisms against ROS may contribute to the development of new anti-tuberculosis therapies. Here we identified genes involved in such mechanisms by screening a high-density transposon mutant library, and we show that several of them are involved in the intracellular lifestyle of the pathogen. Many of these genes were found to play a part in cell envelope functions, further strengthening the important role of the mycobacterial cell envelope in protection against aggressions such as the ones caused by ROS inside host cells.

SummaryBuruli ulcer (BU) is the third most common mycobacterial disease in immunocompetent hosts. BU is caused by Mycobacterium ulcerans, which produces skin ulcers and necrosis at the site of infection. The principal virulence factor of M. ulcerans is a polyketide-derived macrolide named mycolactone, which has cytotoxic and immunosuppresive activities. We determined the severity of inflammation, histopathology and bacillary loads in the subcutaneous footpad tissue of BALB/c mice infected with 11 different M. ulcerans isolates from diverse geographical areas. Strains from Africa (Benin, Ghana, Ivory Coast) induced the highest inflammation, necrosis and bacillary loads, whereas the strains collected from Australia, Asia (Japan, Malaysia, New Guinea), Europe (France) and America (Mexico) induced mild inflammation. Subsequently, animals were infected with the strain that exhibited the highest (Benin) or lowest (Mexico) level of virulence in order to analyse the local immune response generated. The Mexican strain, which does not produce mycolactone, induced a predominantly T helper type 1 (Th1) cytokine profile with constant high expression of the anti-microbial peptides beta defensins 3 and 4, in co-existence with low expression of the anti-inflammatory cytokines interleukin (IL)-10, IL-4 and transforming growth factor (TGF)-b. The highly virulent strain from Benin which produces mycolactone A/B induced the opposite pattern. Thus, different local immune responses were found depending on the infecting M. ulcerans strain.

There are many resources available to mycobacterial researchers, including culture collections around the world that distribute biomaterials to the general scientific community, genomic and clinical databases, and powerful bioinformatics tools. However, many of these resources may be unknown to the research community. This review article aims to summarize and publicize many of these resources, thus strengthening the quality and reproducibility of mycobacterial research by providing the scientific community access to authenticated and quality-controlled biomaterials and a wealth of information, analytical tools and research opportunities.

Six Gram-negative, non-motile, non-spore-forming, non-pigmented, oxidase- and catalase-positive bacterial strains were deposited in 1972, in the Collection of the Institut Pasteur (CIP), Paris, France. The strains, previously identified as members of the genus Moraxella on the basis of their phenotypic and biochemical characteristics, were placed within the genus Psychrobacter based on the results from comparative 16S rRNA gene sequence studies. Their closest phylogenetic relatives were Psychrobacter sanguinis CIP 110993T, Psychrobacter phenylpyruvicus CIP 82.27T and Psychrobacter lutiphocae CIP 110018T. The DNA G+C contents were between 42.1 and 42.7 mol%. The predominant fatty acids were C18 : 1ω9c, C16 : 0, C12 : 0 3-OH, and C18 : 0. Average nucleotide identity between the six strains and their closest phylogenetic relatives, as well as their phenotypic characteristics, supported the assignment of these strains to two novel species within the genus Psychrobacter. The proposed names for these strains are Psychrobacter pasteurii sp. nov., for which the type strain is A1019T (=CIP 110853T=CECT 9184T), and Psychrobacter piechaudii sp. nov., for which the type strain is 1232T (=CIP110854T=CECT 9185T).

HighlightsNovel microbial isolation approach allowed the identification of a Gram-negative Antarctic bacterium belonging to the genus Aequorivita.Aequorivita sp. showed antimicrobial and anthelmintic activity without toxic effect towards eukaryotic cells.The whole genome of Aequorivita sp. was sequenced and compared with other strains to identify biosynthetic gene clusters.This novel approach represents a promising strategy to isolate rare or novel strains useful for biotechnological applications.

The focus of the EU regulations on the Nagoya Protocol on Access and Benefit-Sharing leaves the control of access to genetic resources up to each member state. France has chosen to control access and is going to put in place regulations for it. All the materials received should have specific documentation regarding the accession of genetic resources, where there is a National Authority to issue them. The European commission will maintain a list of biological collections with registered status proposed by each country. The member states are responsible for considering inclusion and verification of these collections. In recent years, the Collection of Institut Pasteur (CIP) staff has expressed concern over how to interact with the implementation of the Nagoya Protocol in the collection but also at the national level with the aim that the CIP will be a registered collection. The advantage of accessing resources from a registered collection is that users of genetic resources will be considered as having exercised ‘due diligence’ if they source their genetic resources from these collections. This could facilitate the process for scientists when applying for research funding. The CIP organized the accession of new deposits and the distribution of micro-organisms in connection with it.