Crucial optimization of translational components towards efficient incorporation of unnatural amino acids into proteins in mammalian cells.

The ability to site-specifically incorporate unnatural amino acids (UAAs) into proteins is a powerful tool in protein engineering. While dozens of UAAs have been successfully introduced into proteins expressed by Escherichia coli cells, it has been much more challenging to create tRNA and tRNA-Synthetase pairs that enable UAAs incorporation, for use in mammalian systems. By altering the orthogonality properties of existing unnatural pairs, previously evolved pairs for use in E. coli could be used in mammalian cells. This would bypass the cumbersome step of having to evolve mutant synthetases and would allow for the rapid development of new mammalian pairs. A major limitation to the amount of UAA-containing proteins that can be expressed in the cell is the availability of UAA-charged orthogonal suppressor tRNA. By using a natural mammalian tRNA promoter, the amount of functional suppressor tRNA can be greatly increased. Furthermore, increasing recognition of the suppressor tRNA by the mutant synthetase will ultimately lead to the appearance of more UAA-charged tRNA

Alignment of the amino acid sequences of the CP1-transplanted mutants.

<p>Inserted CP1 sequences are shown in black. Six sequences used were from <i>E. coli</i> TyrRS, while two were taken from <i>T. thermophilus</i> TyrRS. Both bacterial TyrRSs recognize a G1:C72 containing tyrosyl-tRNA. Each CP1 swapped TyrRS was tested for the ability to charge 1bp-tRNA_CUA in HEK293T cells. (Bioworkbench, SDSC).</p

Characteristics of Seismogenic Dust Particles from a Mountain and Their Significance for Paleoseismic Records in a Tufa Section: A Case Study of Jiuzhaigou, China

The sedimentary characteristics of the special interlayer contained in the section of the Sparkling Lake dam revealed by the 8 August Jiuzhaigou earthquake in 2017 are obviously different from the tufa in the dam body, and they are considered to be historic flood relics. Based on the study of the particulate matter from the 8 August Jiuzhaigou earthquake, this study combined comparative petrographic, mineralogical, geochemical, and chronological studies of the special interbedded sediments of the Sparkling Lake dam with other genetic samples to obtain homology information and genetic links and to explore the tufa depositional dynamics and earthquake disaster subsidence. The paleoseismic benefit in the discontinuity layer was explored, and the paleoseismic information embedded in the profiles was extracted, providing a new idea for reconstructing the paleoseismic events in the tufa deposition sequence. According to X-ray diffraction, laser particle size analysis, and scanning electron microscope experiments, the particulate matter in the Jiuzhaigou mountains has its own specific mineralogical characteristics. The mineral composition of the particulate matter is basically calcite. The particle size is large, and single particles are mostly angular and subangular. The fracture morphology observed under the single-particle microscope was uneven, showing the characteristics of the dust caused by earthquake disasters. The geochemical analysis data show that the distribution patterns of rare earth elements in different types of particulate matter in the same area have similar characteristics. Moreover, an analysis of the elements Rb, Sr, and Ba shows that the particulate matter in Jiuzhaigou has a strong correlation (R2 = 0.9941), indicating the stability and uniformity of the material source. The source of the particulate matter was limestone of the carbonate strata from the Devonian to the Triassic. Combined with mineralogy and grain size morphology, the interbedded particles in the tufa depositional profile have the potential application of paleoseismic archives to record extreme seismic events. According to the chronological data of the special interlayer sediments in the tufa dam body, the paleoseismic age is inferred to be 1220 30 BP. Therefore, the tufa bedding can be related to the paleoearthquake, and the special interlayer of the tufa section can be used to reconstruct paleoearthquakes

Acceptor stem sequences of the various tRNA constructs.

<p>Each tRNA construct was cloned into a plasmid, downstream of the human H1 promoter. Wt-tRNA_CUA is identical to <i>M. jannaschii</i> tyrosyl-tRNA, except in the anticodon region, where it contains a C35 (pknotsRG, BiBiServ).</p

Assessing the orthogonality of various tRNA constructs in HEK293T cells.

<p>Full-length GFP was visualized by UV-light 72 hours after transfection. Expression of full-length GFP will only occur in the presence of amino acid charged suppressor tRNA. Since no exogenous aaRS was provided, full-length GFP expression implies that endogenous aaRS was able to recognize and charge the tRNA with an amino acid. Cells were transfected with the following plasmids: (A) p-EGFP-N1 (B) p-GFP_39TAG (C) p-GFP_39TAG and H1_wt-tRNA_CUA (D) p-GFP_39TAG and H1_1bp-tRNA_CUA (E) p-GFP_39TAG and H1_2bp-tRNA_CUA (F) p-GFP_39TAG and H1_3bp-tRNA_CUA.</p

Nonclassical crystallization of variable valency metal in the biomineralization process

In nature, microorganisms can coexist and interact with various metals and their metallic compounds, ultimately affecting their migration rate, circulation process, and distribution state in the environment, which confirms that they can participate in every step of the metal geochemical cycle. As the most active and powerful geological force in the earth’s surface biosphere, the biological action will inevitably have a great influence on the formation and transformation of sedimentary lithosphere minerals. Of which, biomineralization refers to the process by which living forms influence the precipitation of minerals. The microorganisms concentrate aqueous dissolved metals onto cell walls and at intracellular sites during the life cycle and strongly bind metals during early diagenesis. For this process, nonclassical crystals are disequilibrium assemblages, which are created and maintained during life by dynamic metabolism. The biomineralization can be interpreted as an important medium for microbial-mineral-environmental interactions. This chapter mainly reviews nonclassical crystallization behaviors occurring in the biomineralization processes of variable valency cations (As, Cr, Fe, Mn, and U). The nonclassical crystallization behaviors of variable valency cations (As, Cr, Fe, and Mn) for biomineralization and the nonclassical crystallization behaviors in the biomineralization processes with U by plants and microbes are discussed

Travertine/tufa resource conservation and sustainable development call for a world-wide initiative

Travertine/Tufa landscape is an important heritage and ecological wealth given to mankind by nature. Travertine/Tufa itself has excellent scientific and aesthetic value, mostly with geological archives such as volcanoes, tectonics, and glaciers, as well as fingerprints referring to climate and evolution of life. However, these travertine/tufa landscapes also face degradation and disappearance caused by climate change, natural disasters, and human activities. Strengthening the conservation and sustainable development of the world's travertine/tufa resources is not only a slogan, but also requires the creation of a linked platform for the conservation of travertine/tufa resources with the participation of people from all over the world. This implies the necessity of sharing of databases and technical reserves, and the involvement of more people in the conservation of travertine/tufa resources through the construction of travertine/tufa culture. By recognizing the urgency of travertine/tufa resource conservation, this paper proposes four initiatives for travertine/tufa research aimed at guiding further research and promoting international cooperation to achieve effective conservation and sustainable development of the world's travertine/tufa resources.Fil: Dong, Faqin. Southwest University Of Science And Technology; ChinaFil: Dai, Qunwei. Southwest University Of Science And Technology; ChinaFil: Jiang, Zhongcheng. Chinese Academy of Geological Sciences; ChinaFil: Chen, Xiaoqing. Chinese Academy of Sciences; República de ChinaFil: Xu, Ronglin. Huanglong National Scenic Resort Administrative Bureau; ChinaFil: Zhang, Qiang. Chinese Academy Of Geological Sciences; ChinaFil: An, Dejun. Huanglong National Scenic Resort Administrative Bureau; ChinaFil: Li, Qiongfang. Southwest University Of Science And Technology; ChinaFil: Zhang, Ting. Southwest University Of Science And Technology; ChinaFil: Andelka, Plenkovic-Moraj. University Of Zagreb; CroaciaFil: Capezzuoli, Enrico. Università degli Studi di Firenze; ItaliaFil: Li, Bowen. Michigan Technological University; Estados UnidosFil: Mors, Rodolfo Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentina. Universidad Nacional de Córdoba; Argentin