Synthetic Biology and the United Nations

Synthetic biology is a rapidly emerging interdisciplinary field of science and engineering that aims to redesign living systems through reprogramming genetic information. The field has catalysed global debate among policymakers and publics. Here we describe how synthetic biology relates to these international deliberations, particularly the Convention on Biological Diversity (CBD)

A Novel Obligate Intracellular Gamma-Proteobacterium Associated with Ixodid Ticks, Diplorickettsia massiliensis, Gen. Nov., Sp. Nov

Background: Obligate intracellular bacteria of arthropods often exhibit a significant role in either human health or arthropod ecology. Methodology/Principal Findings: An obligate intracellular gamma-proteobacterium was isolated from the actively questing hard tick Ixodes ricinus using mammalian and amphibian cell lines. Transmission electron microscopy revealed a unique morphology of the bacterium, including intravacuolar localization of bacteria grouped predominantly in pairs and internal structures composed of electron-dense crystal-like structures and regular multilayer sheath-like structures. The isolate 20B was characterized to determine its taxonomic position using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that this strain belongs to the family Coxiellaceae, order Legionellales of Gamma-proteobacteria, and the closest relatives are different Rickettsiella spp. The level of 16S rRNA gene sequence similarity between strain 20B and other recognized species of the family was below 94.5%. Partial sequences of the rpoB, parC and ftsY genes confirmed the phylogenetic position of the new isolate. The G+C content estimated on the basis of whole genome analysis of strain 20B was 37.88%. On the basis of its phenotypic and genotypic properties, together with phylogenetic distinctiveness, we propose that strain 20B to be classified in the new genus Diplorickettsia as the type strain of a novel species named Diplorickettsia massiliensis sp. nov. Conclusions/Significance: Considering the source of its isolation (hard tick, often biting humans) the role of this bacterium in the pathology of humans, animals and ticks should be further investigated

Optimized fixation of actin filaments for improved indirect immunofluorescence staining of rickettsiae

International audienc

Rickettsial infections of the central nervous system

International audienceAs a result of migrations and globalization, people may face a possible increase in the incidence of central nervous system rickettsial infections (CNS R). These diseases, caused by Rickettsia species and transmitted to humans by arthropod bites, are putatively lethal. However , the diagnosis of CNS R is challenging and often delayed due to their nonspecific clinical presentation and the strict intracellular nature of rickettsiae. Furthermore, transfer of rickettsiae to the brain parenchyma is not yet understood. The aim of this review is to analyze and summarize the features and correlated findings of CNS R in order to focus attention on these intriguing but frequently neglected illnesses. We also incorporated data on CNS infections caused by Rickettsia-related microorganisms

Strain 20B bacteria grown in XTC-2 cells.

<p>Transmission electron microscopy; staining with uranyl acetate. The number of bacteria per vacuole (B/v) is indicated by arrows.</p

Strain 20B bacteria grown in XTC-2 cells Transmission electron microscopy; staining with uranyl acetate.

<p>The bacteria in the process of division.</p

Phylogenetic tree based on aligned complete sequences of the <i>rrs</i> (16SrRNA) gene and constructed by the UPGMA method.

<p>The numbers in the nodes represent bootstrap values. The tree shows the position of <i>Diplorickettsia massiliensis</i> (isolate 20B) among recognized bacterial species and <i>rrs</i> genes amplified from uncultured bacteria and environmental samples (Genbank). The host (if any) or the source of amplification is indicated in the brackets; GenBank accession number is indicated at the end of the line for each sequence.</p