In this work,we study the structural changes of the polar[NH4][Cd(HCOO)3]hybrid perovskite under external hydrostatic pressure.We report a reversible framework rearrangement as a function of pressure characterized by:...In this work,we study the structural changes of the polar[NH4][Cd(HCOO)3]hybrid perovskite under external hydrostatic pressure.We report a reversible framework rearrangement as a function of pressure characterized by:(i)a gradual modification of one formate ligand,which changes its coordination mode from a bridging syn–anti mode at atmospheric pressure(LP-phase)to a chelating-anti mode at high-pressure(HP-phase)and(ii)a change in the coordination of the Cd2+cations from six-coordinated(LP-phase)to hepta-coordinated(HP-phase).Very interestingly,this unprecedented framework arrangement displays a large electrical polarization.For instance,the polarization value observed at p=17.7 GPa is about four times the polarization at atmospheric pressure.Therefore,we report that the external pressure induces a novel framework rearrangement in the polar[NH4][Cd(HCOO)3]hybrid perovskite with enhanced electrical polarization.This structure–property relationship offers new insights for designing novel ferroelectric materials based on pressure-responsive hybrid perovskite materials.展开更多
In the biotechnological industry,multicopy gene integration represents an effective strategy to maintain a high-level production of recombinant proteins and to assemble multigene biochemical pathways.In this study,we ...In the biotechnological industry,multicopy gene integration represents an effective strategy to maintain a high-level production of recombinant proteins and to assemble multigene biochemical pathways.In this study,we developed copper-induced in vivo gene amplification in budding yeast for multicopy gene expressions.To make copper as an effective selection pressure,we first constructed a copper-sensitive yeast strain by deleting the CUP1 gene encoding a small metallothionein-like protein for copper resistance.Subsequently,the reporter gene fused with a proline-glutamate-serine-threonine-destabilized CUP1 was integrated at the δ sites of retrotransposon(Ty)elements to counter the copper toxicity at 100 μM Cu^(2+).We further demonstrated the feasibility of modulating chromosomal rearrangements for increased protein expression under higher copper concentrations.In addition,we also demonstrated a simplified design of integrating the expression cassette at the CUP1 locus to achieve tandem duplication under high concentrations of copper.Taken together,we envision that this method of copper-induced in vivo gene amplification would serve as a robust and useful method for protein overproduction and metabolic engineering applications in budding yeast.展开更多
基金supported by the Ministerio de Economía y Competitividad(MINECO)and EU-FEDER under the projects[CSD2007-00045,CTQ2015-67755-C2-1-R and MAT2017-86453-R]Ministerio de Ciencia,Innovación y Universidades(MICINN)and EU-FEDER under the project PGC2018-094814-B-C21Xunta de Galicia under the project ED431C2018/39.
文摘In this work,we study the structural changes of the polar[NH4][Cd(HCOO)3]hybrid perovskite under external hydrostatic pressure.We report a reversible framework rearrangement as a function of pressure characterized by:(i)a gradual modification of one formate ligand,which changes its coordination mode from a bridging syn–anti mode at atmospheric pressure(LP-phase)to a chelating-anti mode at high-pressure(HP-phase)and(ii)a change in the coordination of the Cd2+cations from six-coordinated(LP-phase)to hepta-coordinated(HP-phase).Very interestingly,this unprecedented framework arrangement displays a large electrical polarization.For instance,the polarization value observed at p=17.7 GPa is about four times the polarization at atmospheric pressure.Therefore,we report that the external pressure induces a novel framework rearrangement in the polar[NH4][Cd(HCOO)3]hybrid perovskite with enhanced electrical polarization.This structure–property relationship offers new insights for designing novel ferroelectric materials based on pressure-responsive hybrid perovskite materials.
基金supported by the National Natural Science Foundation of China(grant no.32270087)Daan Gene(20223160A0063)ZhenSheng Biotech.
文摘In the biotechnological industry,multicopy gene integration represents an effective strategy to maintain a high-level production of recombinant proteins and to assemble multigene biochemical pathways.In this study,we developed copper-induced in vivo gene amplification in budding yeast for multicopy gene expressions.To make copper as an effective selection pressure,we first constructed a copper-sensitive yeast strain by deleting the CUP1 gene encoding a small metallothionein-like protein for copper resistance.Subsequently,the reporter gene fused with a proline-glutamate-serine-threonine-destabilized CUP1 was integrated at the δ sites of retrotransposon(Ty)elements to counter the copper toxicity at 100 μM Cu^(2+).We further demonstrated the feasibility of modulating chromosomal rearrangements for increased protein expression under higher copper concentrations.In addition,we also demonstrated a simplified design of integrating the expression cassette at the CUP1 locus to achieve tandem duplication under high concentrations of copper.Taken together,we envision that this method of copper-induced in vivo gene amplification would serve as a robust and useful method for protein overproduction and metabolic engineering applications in budding yeast.
