The African BioGenome Project (AfricaBP) Open Institute for Genomics and Bioinformatics aims to overcome barriers to capacity building through its distributed African regional workshops and prioritizes the exchange of grassroots knowledge and innovation in biodiversity genomics and bioinformatics. In 2023, we implemented 28 workshops on biodiversity genomics and bioinformatics, covering 11 African countries across the 5 African geographical regions. These regional workshops trained 408 African scientists in hands-on molecular biology, genomics and bioinformatics techniques as well as the ethical, legal and social issues associated with acquiring genetic resources.
View Article and Find Full Text PDFArtificial molecular motors have the potential to generate mechanical work on their environment by producing autonomous unidirectional motions when supplied with a source of energy. However, the harnessing of this mechanical work to subsequently activate various endoenergetic processes that can be useful in materials science remains elusive. Here, it is shown that by integrating a light-driven rotary motor through hydrogen bonds in a β-amyloid-like structure forming supramolecular hydrogels, the mechanical work generated during the constant rotation of the molecular machine under UV irradiation is sufficient to disrupt the β-amyloid fibers and to trigger a gel-to-sol transition at macroscopic scale.
View Article and Find Full Text PDFThe culturomics method enabled isolation of a new member of the Ottowia genus from the stool sample of a healthy volunteer. Strain Marseille-P4747T exhibited a 96.18% 16S rRNA sequence identity with Ottowia beijingensis strain GCS-AN-3 (NR_133803.
View Article and Find Full Text PDFFEMS Microbiol Lett
September 2022
Strain Marseille-P4119T was isolated from a faecal sample of a healthy 32-year-old faecal transplant donor. The bacterium was anaerobic, Gram-negative, rod-shaped, non-motile, and did not produce spores. We studied its phenotypic characteristics and sequenced its whole genome.
View Article and Find Full Text PDFSelf-assembly and molecular recognition are critical processes both in life and material sciences. They usually depend on strong, directional non-covalent interactions to gain specificity and to make long-range organization possible. Most supramolecular constructs are also at least partially governed by topography, whose role is hard to disentangle.
View Article and Find Full Text PDFStrain SN6 is a non-motile and non-spore-forming gram-negative bacterium which was isolated from the stool sample of an Amazonian patient. The optimum growth was observed at 37 °C, pH 7, and 0-5 g/l of NaCl. Based on the 16S rRNA gene sequence similarity, the strain SN6 exhibited 97.
View Article and Find Full Text PDFA -symmetric triarylamine-based macrocycle (i.e., hexaaza[1]paracyclophane), decorated with six lateral amide functions, is synthesized by a convergent and modular strategy.
View Article and Find Full Text PDFBackground: In Marseille, France, the COVID-19 incidence evolved unusually with several successive epidemic phases. The second outbreak started in July, was associated with North Africa, and involved travelers and an outbreak on passenger ships. This suggested the involvement of a new viral variant.
View Article and Find Full Text PDFBackground: Streptococcus pneumoniae serotype 1 remains a leading cause of invasive pneumococcal diseases, even in countries with PCV-10/PCV-13 vaccine implementation. The main objective of this study, which is part of the Pneumococcal African Genome project (PAGe), was to determine the phylogenetic relationships of serotype 1 isolates recovered from children patients in Casablanca (Morocco), compared to these from other African countries; and to investigate the contribution of accessory genes and recombination events to the genetic diversity of this serotype.
Results: The genome average size of the six-pneumococcus serotype 1 from Casablanca was 2,227,119 bp, and the average content of coding sequences was 2113, ranging from 2041 to 2161.
Dendrons consisting of two phosphonate functions and three oligo(ethylene glycol) (OEG) chains grafted on a central phenoxyethylcarbamoylphenoxy group were synthesized and investigated as Langmuir monolayers at the surface of water. The OEG chain in the position was grafted with a -Bu end-group, a hydrocarbon chain, or a partially fluorinated chain. These dendrons are models of structurally related OEG dendrons that were found to significantly improve the stability of aqueous dispersions of iron oxide nanoparticles when grafted on their surface.
View Article and Find Full Text PDFDendrons fitted with three oligo(ethylene glycol) (OEG) chains, one of which contains a fluorinated or hydrogenated end group and bears a bisphosphonate polar head (C X OEGDen, X = F or H; = 2 or 4), were synthesized and grafted on the surface of iron oxide nanoparticles (IONPs) for microbubble-mediated imaging and therapeutic purposes. The size and stability of the dendronized IONPs (IONP@C X OEGDen) in aqueous dispersions were monitored by dynamic light scattering. The investigation of the spontaneous adsorption of IONP@C X OEGDen at the interface between air or air saturated with perfluorohexane and an aqueous phase establishes that exposure to the fluorocarbon gas markedly increases the rate of adsorption of the dendronized IONPs to the gas/water interface and decreases the equilibrium interfacial tension.
View Article and Find Full Text PDFA platinum (II) complex stabilized by a pyridine and an N-heterocyclic carbene ligand featuring an anthracenyl moiety was prepared. The compound was fully characterized and its molecular structure was determined by single-crystal X-ray diffraction. The compound demonstrated high in vitro antiproliferative activities against cancer cell lines with IC ranging from 10 to 80 nM.
View Article and Find Full Text PDFC -Symmetric triarylamine trisamides (TATAs), decorated with three norbornene end groups, undergo supramolecular polymerization and further gelation by π-π stacking and hydrogen bonding of their TATA cores. By using subsequent ring-opening metathesis polymerization, these physical gels are permanently crosslinked into chemical gels. Detailed comparisons of the supramolecular stacks in solution, in the physical gel, and in the chemical gel states, are performed by optical spectroscopies, electronic spectroscopies, atomic force microscopy, electronic paramagnetic resonance spectroscopy, X-ray scattering, electronic transport measurements, and rheology.
View Article and Find Full Text PDFUpon cooling in solution, chiral triarylamine tris-amide unimers produce organogels by stacking into helical supramolecular polymers, which subsequently bundle into larger fibers. Interestingly, circular dichroism, vibrational circular dichroism, and AFM imaging of the chiral self-assemblies revealed that monocolumnar P-helical fibrils formed upon fast cooling, whereas bundled M-superhelical fibers formed upon slow cooling. The mechanistic study of this structural bifurcation reveals the presence of a strong memory effect, reminiscent of a complex stepwise combination of primary and secondary nucleation-growth processes.
View Article and Find Full Text PDFStrain Marseille-P4006, a Gram-stain-positive, rod-shaped, non-sporulating, facultatively anaerobic bacterium, was isolated from the vaginal swab of a 45-year-old woman with recurrent bacterial vaginosis. We studied its phenotypic characteristics and sequenced its whole genome. The major fatty acids were C (48%), C (14%) and C (11%).
View Article and Find Full Text PDFStrain Marseille-P4121 was isolated from a vaginal sample of a 45-year-old French woman with bacterial vaginosis. It is a Gram-positive, asporogenous, non-motile and aerobic bacterium. Strain Marseille-P4121 exhibits 98.
View Article and Find Full Text PDFGaining control over supramolecular polymerization mechanisms is of high fundamental interest to understand self-assembly and self-organization processes at the nanoscale. It is also expected to significantly impact the design and improve the efficiency of advanced materials and devices. Up to now, supramolecular polymerization has been shown to take place from unimers in solution, mainly by variations of temperature or of concentration.
View Article and Find Full Text PDFA clickable fullerene hexa-adduct scaffold has been functionalized with twelve triarylamine subunits. The light-triggered self-assembly of this molecular unit leads to 3D honeycomb-like structures with inner pores of around 10 nm diameter. Multiple grafting of triarylamine subunits onto a hard-core C unit increases the dimensionality of the self-assembly process by reticulating the 1D nanowires typically obtained from the supramolecular polymerization of triarylamine monomers.
View Article and Find Full Text PDFIn this article, we present the draft genome sequence of strain Marseille-P3344, isolated from a human fecal sample. The genome described here is composed of 2,464,704 nucleotides, with 2,230 protein-coding genes and 76 RNA genes.
View Article and Find Full Text PDFThe study of supramolecular polymers in the bulk, in diluted solution, and at the solid-liquid interface has recently become a major topic of interest, going from fundamental aspects to applications in materials science. However, examples of supramolecular polymers at the liquid-liquid interface are mostly unexplored. Here, we describe the supramolecular polymerization of triarylamine molecules and their light-triggered organization at a chloroform-water interface.
View Article and Find Full Text PDFBiocompatible silica-based mesoporous materials, which present high surface areas combined with uniform distribution of nanopores, can be organized in functional nanopatterns for a number of applications. However, silica is by essence an electrically insulating material which precludes applications for electro-chemical devices. The formation of hybrid electroactive silica nanostructures is thus expected to be of great interest for the design of biocompatible conducting materials such as bioelectrodes.
View Article and Find Full Text PDFMetallic nanostructures are able to interact with an incident electromagnetic field at subwavelength scales by plasmon resonance which involves the collective oscillation of conduction electrons localized at their surfaces. Among several possible applications of this phenomenon, the theoretical prediction is that optical circuits connecting multiple plasmonic elements will surpass classical electronic circuits at nanoscale because of their much faster light-based information processing. However, the placement and coupling of metallic elements smaller than optical wavelengths currently remain a formidable challenge by top-down manipulations.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2016
An acid-base switchable [c2]daisy chain rotaxane terminated with two 2,6-diacetylamino pyridine units has been self-assembled with a bis(uracil) linker. The complementary hydrogen-bond recognition patterns, together with lateral van der Waals aggregations, result in the hierarchical formation of unidimensional supramolecular polymers associated in bundles of muscle-like fibers. Microscopic and scattering techniques reveal that the mesoscopic structure of these bundles depends on the extended or contracted states that the rotaxanes show within individual polymer chains.
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