Genetic Engineering of Schizosaccharomyces pombe to Produce Bacterial Polyhydroxyalkanotes

A commercial use of microbial produced products, like polyhydroxyalkanotes (PHAs), in the sense of an environmental precaution appears meaningful and necessary. In order to more economically produce microbial products, this investigation was focused on suitable producers, like the yeast Schizosaccharomyces pombe. Since it is not capable of the PHA synthesis, easily cultured and they must be modified genetically. Therefore, the genes of the phb biosynthesis pathway of Ralstonia eutropha [beta-ketothiolase (phbARe); acetoacetyl-CoA reductase (phbBRe); as well as phb synthase (phbCRe), located onto the plasmid pBHR68 were cloned into the cohesive ended pYIplac128 integrated vector that transformed into the chromosome of the yeast Schizosaccharomyces pombe strain Q01. Under the optimized cultivation conditions, the transgenic yeast S. pombe strain Q01/phb was able to produce phb and accumulated up to 9.018 % phb. The presence of heterologous DNA in the transgenic yeast was examined by means of Western blot analysis. In addition, both PHA synthase activity and kinetics were determined. The UV/Vis, 1H and 13C NMR spectral analysis have confirmed that the polymer produced by the yeast S. pombe strain Q01/phb is a pure homopolymer of 3-hydroxybutyric acid

A modified vaccinia Ankara vaccine expressing spike and nucleocapsid protects rhesus macaques against SARS-CoV-2 Delta infection

SARS-CoV-2 vaccines should induce broadly cross-reactive humoral and T cell responses to protect against emerging variants of concern (VOCs). Here, we inactivated the furin cleavage site (FCS) of spike expressed by a modified vaccinia Ankara (MVA) virus vaccine (MVA/SdFCS) and found that FCS inactivation markedly increased spike binding to human ACE2. After vaccination of mice, the MVA/SdFCS vaccine induced eightfold higher neutralizing antibodies compared with MVA/S, which expressed spike without FCS inactivation, and protected against the Beta variant. We next added nucleocapsid to the MVA/SdFCS vaccine (MVA/SdFCS-N) and tested its immunogenicity and efficacy via intramuscular (IM), buccal (BU), or sublingual (SL) routes in rhesus macaques. IM vaccination induced spike-specific IgG in serum and mucosae (nose, throat, lung, and rectum) that neutralized the homologous (WA-1/2020) and heterologous VOCs, including Delta, with minimal loss (<2-fold) of activity. IM vaccination also induced both spike- and nucleocapsid-specific CD4 and CD8 T cell responses in the blood. In contrast, the SL and BU vaccinations induced less spike-specific IgG in secretions and lower levels of polyfunctional IgG in serum compared with IM vaccination. After challenge with the SARS-CoV-2 Delta variant, the IM route induced robust protection, the BU route induced moderate protection, and the SL route induced no protection. Vaccine-induced neutralizing and non-neutralizing antibody effector functions positively correlated with protection, but only the effector functions correlated with early protection. Thus, IM vaccination with MVA/SdFCS-N vaccine elicited cross-reactive antibody and T cell responses, protecting against heterologous SARS-CoV-2 VOC more effectively than other routes of vaccination

SARS-CoV-2 RBD trimer protein adjuvanted with Alum-3M-052 protects from SARS-CoV-2 infection and immune pathology in the lung

There is a great need for the development of vaccines that induce potent and long-lasting protective immunity against SARS-CoV-2. Multimeric display of the antigen combined with potent adjuvant can enhance the potency and longevity of the antibody response. The receptor binding domain (RBD) of the spike protein is a primary target of neutralizing antibodies. Here, we developed a trimeric form of the RBD and show that it induces a potent neutralizing antibody response against live virus with diverse effector functions and provides protection against SARS-CoV-2 challenge in mice and rhesus macaques. The trimeric form induces higher neutralizing antibody titer compared to monomer with as low as 1μg antigen dose. In mice, adjuvanting the protein with a TLR7/8 agonist formulation alum-3M-052 induces 100-fold higher neutralizing antibody titer and superior protection from infection compared to alum. SARS-CoV-2 infection causes significant loss of innate cells and pathology in the lung, and vaccination protects from changes in innate cells and lung pathology. These results demonstrate RBD trimer protein as a suitable candidate for vaccine against SARS-CoV-2

National identity predicts public health support during a global pandemic

Changing collective behaviour and supporting non-pharmaceutical interventions is an important component in mitigating virus transmission during a pandemic. In a large international collaboration (Study 1, N = 49,968 across 67 countries), we investigated self-reported factors associated with public health behaviours (e.g., spatial distancing and stricter hygiene) and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stage of the COVID-19 pandemic (April-May 2020). Respondents who reported identifying more strongly with their nation consistently reported greater engagement in public health behaviours and support for public health policies. Results were similar for representative and non-representative national samples. Study 2 (N = 42 countries) conceptually replicated the central finding using aggregate indices of national identity (obtained using the World Values Survey) and a measure of actual behaviour change during the pandemic (obtained from Google mobility reports). Higher levels of national identification prior to the pandemic predicted lower mobility during the early stage of the pandemic (r = −0.40). We discuss the potential implications of links between national identity, leadership, and public health for managing COVID-19 and future pandemics.publishedVersio

Chargelocationeffectonthehydrationpropertiesofsyntheticsaponiteandhectorite saturated byNa+, Ca2+cations:XRDinvestigation

International audienceThispaperaimsatcomparingtheeffectofchargelocationonthehydrationpropertiesof twotrioctahedral syntheticminerals:saponiteandhectorite. Thesampleswerecharacterisedbyalayerchargeof 0.4charge perhalfunitcellandweresaturatedwithNa+orCa2+. Thehydrationbehaviourwasstudiedbydetermining thestructural characteristicswhichwereobtainedbymodellingXRDpatterns. XRDpatternswererecordedundercontrolledrelativehumidity(RH). Thehydratedstatesof Ca-hectorite weremorehomogeneousthanthoseofsaponitewhereasthetransitionfrom1Wto2WoccurredatlowerRH rates for saponitethanfor hectorite. For heterogeneous samples, the1Wand2Wlayers werestacked randomlyfashionforhectorite. Na-saponite-0.4andCa-saponite-0.4weremadeupof typesof layer; one waterlayer(1W)andtwo-waterlayers(2W). Thestackingof theselayersshowedsomesegregation

Study of the structural evolution and selectivity of Wyoming montmorillonite in relation with the concentration of Cu2+ and Ni2+

International audienc

Genetic Engineering of Schizosaccharomyces pombe to Produce Bacterial Polyhydroxyalkanotes

A commercial use of microbial produced products, like polyhydroxyalkanotes (PHAs), in the sense of an environmental precaution appears meaningful and necessary. In order to more economically produce microbial products, this investigation was focused on suitable producers, like the yeast Schizosaccharomyces pombe. Since it is not capable of the PHA synthesis, easily cultured and they must be modified genetically. Therefore, the genes of the phb biosynthesis pathway of Ralstonia eutropha [beta-ketothiolase (phbARe); acetoacetyl-CoA reductase (phbBRe); as well as phb synthase (phbCRe), located onto the plasmid pBHR68 were cloned into the cohesive ended pYIplac128 integrated vector that transformed into the chromosome of the yeast Schizosaccharomyces pombe strain Q01. Under the optimized cultivation conditions, the transgenic yeast S. pombe strain Q01/phb was able to produce phb and accumulated up to 9.018 % phb. The presence of heterologous DNA in the transgenic yeast was examined by means of Western blot analysis. In addition, both PHA synthase activity and kinetics were determined. The UV/Vis, 1H and 13C NMR spectral analysis have confirmed that the polymer produced by the yeast S. pombe strain Q01/phb is a pure homopolymer of 3-hydroxybutyric acid

Biosynthesis Of Polyhydroxyalkanotes In Wildtype Yeasts

Biosynthesis of the biodegradable polymers polyhydroxyalkanotes (PHAs) are studied extensively in wild type and genetically modified prokaryotic cells, however the content and structure of PHA in wild type yeasts are not well documented. The purpose of this study was to screen forty yeast isolates collected from different Egyptian ecosystems for their ability to accumulate PHAs. Identification of the isolates and characterization of PHAs produced by the positive strains in the Nile-red staining assay was envisaged. One positive isolates which was identified using the API 20C yeast identification system as Rhodotorula minuta strain RY4 produced 2% of PHA in biomass, in glucose, oleic acid and tween 60 containing medium, over a growth period of 96 h. The nature of the PHA thus produced was analyzed by infrared spectroscopy and nuclear magnetic resonance (1H and 13C NMR) and found to contain polyhydroxybutyrate and polyhydroxyvalerate. This study shows for the first time monomer detection by 1H and/or 13C NMR of PHA polymers synthesized in wild type yeasts