A novel supramolecular organic-inorganic adduct containing alpha-Keggin-type [PW12O40](3-) anions and benzo-15-crown-5 molecules

The structure of the title compound, tris(hydroxonium) 12- phosphato-tetracosa- 2-oxo-dodecaoxododecatungsten hexakis( benzo-15-crown-5)±methanol±water (1/1/1), (H3O)3- [PW12O40] 6C14H20O5 CH3OH H2O (where C14H20O5 is benzo-15-crown-5), has been determined at 180 K. [PW12O40]3ÿ anions are typical of -Keggin structures, and the [H3O (C14H20O5)2]+ sandwich-type moieties contain a large number of short O O close contacts, suggesting strong hydrogen bonding within them

Lokiarchaeon is hydrogen dependent

The nature of host that acquired the mitochondrion at eukaryote origin (the host) is an important microbial evolutionary issue. Modern phylogenetics indicate that the host was an archaeon. The metagenome sequence of Candidatus Lokiarchaeon identified it as the closest relative of the host yet known. Here we report comparative genomic evidence indicating that Lokiarchaeaon is hydrogen-dependent, as one theory for eukaryote origin — the hydrogen hypothesis — predicted for the host lineage

The application of Bonelike® Poro as a synthetic bone substitute for the management of critical-sized bone defects - A comparative approach to the autograft technique - A preliminary study

The effective treatment of non-unions and critical-sized defects remains a challenge in the orthopedic field. From a tissue engineering perspective, this issue can be addressed through the application bioactive matrixes to support bone regeneration, such as Bonelike®, as opposed to the widespread autologous grafting technique. An improved formulation of Bonelike® Poro, was assessed as a synthetic bone substitute in an ovine model for critical-sized bone defects. Bone regeneration was assessed after 5 months of recovery through macro and microscopic analysis of the healing features of the defect sites. Both the application of natural bone graft or Bonelike® Poro resulted in bridging of the defects margins. Untreated defect remained as fibrous non-unions at the end of the study period. The characteristics of the newly formed bone and its integration with the host tissue were assessed through histomorphometric and histological analysis, which demonstrated Bonelike® Poro to result in improved healing of the defects. The group treated with synthetic biomaterial presented bone bridges of increased thickness and bone features that more closely resembled the native spongeous and cortical bone. The application of Bonelike® Poro enabled the regeneration of critical-sized lesions and performed comparably to the autograph technique, validating its octeoconductive and osteointegrative potential for clinical application as a therapeutic strategy in human and veterinary orthopedics.This research was supported by Projects PEst-OE/AGR/UI0211/2011 from FCT , and COMPETE 2020 , from ANI – Projetos ID&T Empresas em Copromoção , by the project “insitu.Biomas – Reinvent biomanufacturing systems by using an usability approach for in situ clinic temporary implants fabrication” with the reference POCI-01-0247-FEDER-017771 , by the project “Print-on-Organs – Engineering bioinks and processes for direct printing on organs” with the reference POCI-01-0247-FEDER-033877 , and by the project “Bone2Move - Development of ‘in vivo’ experimental techniques and modelling methodologies for the evaluation of 4D scaffolds for bone defect in sheep model: an integrative research approach” with the reference POCI-01-0145-FEDER-031146 . Mariana Vieira Branquinho ( SFRH/BD/146172/2019 ), Ana Catarina Sousa ( SFRH/BD/146689/2019 ), and Rui Damásio Alvites ( SFRH/BD/116118/2016 ), acknowledge FCT , for financial support. This research was supported by Projects PEst-OE/AGR/UI0211/2011 from FCT, and COMPETE 2020, from ANI ? Projetos ID&T Empresas em Copromo??o, by the project ?insitu.Biomas ? Reinvent biomanufacturing systems by using an usability approach for in situ clinic temporary implants fabrication? with the reference POCI-01-0247-FEDER-017771, by the project ?Print-on-Organs ? Engineering bioinks and processes for direct printing on organs? with the reference POCI-01-0247-FEDER-033877, and by the project ?Bone2Move - Development of ?in vivo? experimental techniques and modelling methodologies for the evaluation of 4D scaffolds for bone defect in sheep model: an integrative research approach? with the reference POCI-01-0145-FEDER-031146. Mariana Vieira Branquinho (SFRH/BD/146172/2019), Ana Catarina Sousa (SFRH/BD/146689/2019), and Rui Dam?sio Alvites (SFRH/BD/116118/2016), acknowledge FCT, for financial support

Biology of archaea from a novel family Cuniculiplasmataceae (Thermoplasmata) ubiquitous in hyperacidic environments

The order Thermoplasmatales (Euryarchaeota) is represented by the most acidophilic organisms known so far that are poorly amenable to cultivation. Earlier culture-independent studies in Iron Mountain (California) pointed at an abundant archaeal group, dubbed 'G-plasma'. We examined the genomes and physiology of two cultured representatives of a Family Cuniculiplasmataceae, recently isolated from acidic (pH 1-1.5) sites in Spain and UK that are 16S rRNA gene sequence-identical with 'G-plasma'. Organisms had largest genomes among Thermoplasmatales (1.87-1.94 Mbp), that shared 98.7-98.8% average nucleotide identities between themselves and 'G-plasma' and exhibited a high genome conservation even within their genomic islands, despite their remote geographical localisations. Facultatively anaerobic heterotrophs, they possess an ancestral form of A-type terminal oxygen reductase from a distinct parental clade. The lack of complete pathways for biosynthesis of histidine, valine, leucine, isoleucine, lysine and proline pre-determines the reliance on external sources of amino acids and hence the lifestyle of these organisms as scavengers of proteinaceous compounds from surrounding microbial community members. In contrast to earlier metagenomics-based assumptions, isolates were S-layer-deficient, non-motile, non-methylotrophic and devoid of iron-oxidation despite the abundance of methylotrophy substrates and ferrous iron in situ, which underlines the essentiality of experimental validation of bioinformatic predictions

Photocatalytic activity of nanostructured anatase coatings obtained by cold gas spray

This article describes a photocatalytic nanostructured anatase coating deposited by cold gas spray (CGS)supported on titanium sub-oxide (TiO22x) coatings obtained by atmospheric plasma spray (APS) onto stainless steel cylinders. The photocatalytic coating was homogeneous and preserved the composition and nanostructure of the starting powder. The inner titanium sub-oxide coating favored the deposition of anatase particles in the solid state. Agglomerated nano-TiO2 particles fragmented when impacting onto the hard surface of the APS TiO22x bond coat. The rough surface provided by APS provided an ideal scenario for entrapping the nanostructured particles, which may be adhered onto the bond coat due to chemical bonding; a possible bonding mechanism is described. Photocatalytic experiments showed that CGS nano-TiO2 coating was active for photodegrading phenol and formic acid under aqueous conditions. The results were similar to the performance obtained by competitor technologies and materials such as dip-coating P25 photocatalysts. Disparity in the final performance of the photoactive materials may have been caused by differences in grain size and the crystalline composition of titanium dioxide

A fresh look at the evolution and diversification of photochemical reaction centers

In this review, I reexamine the origin and diversification of photochemical reaction centers based on the known phylogenetic relations of the core subunits, and with the aid of sequence and structural alignments. I show, for example, that the protein folds at the C-terminus of the D1 and D2 subunits of Photosystem II, which are essential for the coordination of the water-oxidizing complex, were already in place in the most ancestral Type II reaction center subunit. I then evaluate the evolution of reaction centers in the context of the rise and expansion of the different groups of bacteria based on recent large-scale phylogenetic analyses. I find that the Heliobacteriaceae family of Firmicutes appears to be the earliest branching of the known groups of phototrophic bacteria; however, the origin of photochemical reaction centers and chlorophyll synthesis cannot be placed in this group. Moreover, it becomes evident that the Acidobacteria and the Proteobacteria shared a more recent common phototrophic ancestor, and this is also likely for the Chloroflexi and the Cyanobacteria. Finally, I argue that the discrepancies among the phylogenies of the reaction center proteins, chlorophyll synthesis enzymes, and the species tree of bacteria are best explained if both types of photochemical reaction centers evolved before the diversification of the known phyla of phototrophic bacteria. The primordial phototrophic ancestor must have had both Type I and Type II reaction centers

Capsules from Pathogenic and Non-Pathogenic Cryptococcus spp. Manifest Significant Differences in Structure and Ability to Protect against Phagocytic Cells

Capsule production is common among bacterial species, but relatively rare in eukaryotic microorganisms. Members of the fungal Cryptococcus genus are known to produce capsules, which are major determinants of virulence in the highly pathogenic species Cryptococcus neoformans and Cryptococcus gattii. Although the lack of virulence of many species of the Cryptococcus genus can be explained solely by the lack of mammalian thermotolerance, it is uncertain whether the capsules from these organisms are comparable to those of the pathogenic cryptococci. In this study, we compared the characteristic of the capsule from the non-pathogenic environmental yeast Cryptococcus liquefaciens with that of C. neoformans. Microscopic observations revealed that C. liquefaciens has a capsule visible in India ink preparations that was also efficiently labeled by three antibodies generated to specific C. neoformans capsular antigens. Capsular polysaccharides of C. liquefaciens were incorporated onto the cell surface of acapsular C. neoformans mutant cells. Polysaccharide composition determinations in combination with confocal microscopy revealed that C. liquefaciens capsule consisted of mannose, xylose, glucose, glucuronic acid, galactose and N-acetylglucosamine. Physical chemical analysis of the C. liquefaciens polysaccharides in comparison with C. neoformans samples revealed significant differences in viscosity, elastic properties and macromolecular structure parameters of polysaccharide solutions such as rigidity, effective diameter, zeta potential and molecular mass, which nevertheless appeared to be characteristics of linear polysaccharides that also comprise capsular polysaccharide of C. neoformans. The environmental yeast, however, showed enhanced susceptibility to the antimicrobial activity of the environmental phagocytes, suggesting that the C. liquefaciens capsular components are insufficient in protecting yeast cells against killing by amoeba. These results suggest that capsular structures in pathogenic Cryptococcus species and environmental species share similar features, but also manifest significant difference that could influence their potential to virulence