Overexpression of a Designed Mutant Oxyanion Binding Protein ModA/WtpA in for the Low pH Recovery of Molybdenum and Rhenium.

Molybdenum and rhenium are critically important metals for a number of emerging technologies. We identified and characterized a molybdenum/tungsten transport protein (ModA/WtpA) of and demonstrated the binding of tungstate, molybdate, and chromate. We used computational design to expand the binding capabilities of the protein to include perrhenate.

CRISPR/dCas12a knock-down of Acidithiobacillus ferrooxidans electron transport chain bc complexes enables enhanced metal sulfide bioleaching.

Acidithiobacillus ferrooxidans is an acidophilic chemolithoautotroph that plays an important role in biogeochemical iron and sulfur cycling and is a member of the consortia used in industrial hydrometallurgical processing of copper. Metal sulfide bioleaching is catalyzed by the regeneration of ferric iron; however, bioleaching of chalcopyrite, the dominant unmined form of copper on Earth, is inhibited by surface passivation. Here, we report the implementation of CRISPR interference (CRISPRi) using the catalytically inactive Cas12a (dCas12a) in A.

Atomic-Scale Multimodal Characterization of Self-Assembled InAs/InGaAlAs Quantum Dots.

Self-assembled quantum dots (QDs) are potential candidates for photoelectric and photovoltaic devices, because of their discrete energy levels. The characterization of QDs at the atomic level using a multimodal approach is crucial to improving device performance because QDs are nanostructures with highly correlated structural parameters. In this study, scanning transmission electron microscopy, geometric phase analysis, and atom probe tomography were employed to characterize structural parameters such as the shape, strain, and composition of self-assembled InAs-QDs with InGaAlAs spacer layers.

Genetic Modification of for Rare-Earth Element Recovery under Acidic Conditions.

As global demands for rare-earth elements (REEs) continue to grow, the biological recovery of REEs has been explored as a promising strategy, driven by potential economic and environmental benefits. It is known that calcium-binding domains, including helix-loop-helix EF hands and repeats-in-toxin (RTX) domains, can bind lanthanide ions due to their similar ionic radii and coordination preference to calcium. Recently, the lanmodulin protein from was reported, which has evolved a high affinity for lanthanide ions over calcium.

Overexpression of quorum sensing genes in enhances cell attachment and covellite bioleaching.

Cell adhesion is generally a prerequisite to the microbial bioleaching of sulfide minerals, and surface biofilm formation is modulated via quorum sensing (QS) communication. We explored the impact of the overexpression of endogenous QS machinery on the covellite bioleaching capabilities of , a representative acidophilic chemolithoautotrophic bacterium. Cells were engineered to overexpress the endogenous qs-I operon or just the gene under control of the promoter.

The Reductive Leaching of Chalcopyrite by Chromium(II) Chloride for the Rapid and Complete Extraction of Copper.

A hydrometallurgical process is developed to lower the costs of copper production and thereby sustain the use of copper throughout the global transition to renewable energy technologies. The unique feature of the hydrometallurgical process is the reductive treatment of chalcopyrite, which is in contrast to the oxidative treatment more commonly pursued in the literature. Chalcopyrite reduction by chromium(II) ion is described for the first time and superior kinetics are shown.

Atomic-Scale Dynamics at Solid-Liquid Nanointerfaces Induced by Electron-Beam Irradiation.

We report electron-beam induced dynamics at PbS-Pb solid-liquid interfaces. We fabricated PbS-Pb solid-liquid nanointerfaces by heating PbS nanocrystals under vacuum to observe the entire process of structural evolution at the atomic scale. We investigated the dynamics using time-resolved high-angle annular dark-field imaging.

Genome-wide DNA methylation status of Mongolians exhibits signs of cellular stress response related to their nomadic lifestyle.

Background: Epigenetics is crucial for connecting environmental stresses with physiological responses in humans. Mongolia, where nomadic livestock pastoralism has been the primal livelihood, has a higher prevalence of various chronic diseases than the surrounding East Asian regions, which are more suitable for crop farming. The genes related to dietary stress and pathogenesis of related disorders may have varying epigenetic statuses among the human populations with diverse dietary cultures.

Engineering Polyhistidine Tags on Surface Proteins of : Impact of Localization on the Binding and Recovery of Divalent Metal Cations.

Metal processing using microorganisms has many advantages including the potential for reduced environmental impacts as compared to conventional technologies.is an iron- and sulfur-oxidizing chemolithoautotroph that is known to participate in metal bioleaching, and its metabolic capabilities have been exploited for industrial-scale copper and gold biomining. In addition to bioleaching, microorganisms could also be engineered for selective metal binding, enabling new opportunities for metal bioseparation and recovery.

Genetic engineering of the acidophilic chemolithoautotroph Acidithiobacillus ferrooxidans.

There are several natural and anthropomorphic environments where iron- and/or sulfur-oxidizing bacteria thrive in extremely acidic conditions. These acidophilic chemolithautotrophs play important roles in biogeochemical iron and sulfur cycles, are critical catalysts for industrial metal bioleaching operations, and have underexplored potential in future biotechnological applications. However, their unique growth conditions complicate the development of genetic techniques.

Glutathione Synthetase Overexpression in Acidithiobacillus ferrooxidans Improves Halotolerance of Iron Oxidation.

Acidithiobacillus ferrooxidans is a well-studied iron- and sulfur-oxidizing acidophilic chemolithoautotroph that is exploited for its ability to participate in the bioleaching of metal sulfides. Here, we overexpressed the endogenous glutamate-cysteine ligase and glutathione synthetase genes in separate strains and found that glutathione synthetase overexpression increased intracellular glutathione levels. We explored the impact of pH on the halotolerance of iron oxidation in wild-type and engineered cultures.

Dispersion of sulfur creates a valuable new growth medium formulation that enables earlier sulfur oxidation in relation to iron oxidation in Acidithiobacillus ferrooxidans cultures.

Acidithiobacillus ferrooxidans is an acidophilic chemolithoautotroph that is commonly reported to exhibit diauxic population growth behavior where ferrous iron is oxidized before elemental sulfur when both are available, despite the higher energy content of sulfur. We have discovered sulfur dispersion formulations that enables sulfur oxidation before ferrous iron oxidation. The oxidation of dispersed sulfur can lower the culture pH within days below the range where aerobic ferrous iron oxidation can occur.

Enhanced microbial corrosion of stainless steel by Acidithiobacillus ferrooxidans through the manipulation of substrate oxidation and overexpression of rus.

Acidithiobacillus ferrooxidans cells can oxidize iron and sulfur and are key members of the microbial biomining communities that are exploited in the large-scale bioleaching of metal sulfide ores. Some minerals are recalcitrant to bioleaching due to the presence of other inhibitory materials in the ore bodies. Additives are intentionally included in processed metals to reduce environmental impacts and microbially influenced corrosion.

Microbially Influenced Corrosion of Stainless Steel by Acidithiobacillus ferrooxidans Supplemented with Pyrite: Importance of Thiosulfate.

Microbially influenced corrosion (MIC) results in significant damage to metallic materials in many industries. Anaerobic sulfate-reducing bacteria (SRB) have been well studied for their involvement in these processes. Highly corrosive environments are also found in pulp and paper processing, where chloride and thiosulfate lead to the corrosion of stainless steels.

Genetic variants influencing obesity-related traits in Japanese population.

Adipose tissue is the main organ that stores energy and participates in adaptive thermogenesis of the human body. The adipose tissue content in an individual is determined by a combination of genetic factors and lifestyle related factors. While Japanese people, along with the closely related East Asians, are generally thinner than individuals of European ancestry, they are prone to accumulating visceral adipose tissues.

Transposase-Mediated Chromosomal Integration of Exogenous Genes in Acidithiobacillus ferrooxidans.

The development of as a non-model host organism for synthetic biology is hampered by a lack of genetic tools and techniques. New plating and liquid-based selection methods were developed to improve the identification of transformed cell lines. Enabled by these methods, a hyperactive transposase was used to generate mutants with integrated genes for the expression of the superfolder green fluorescent protein (sfGFP) gene or a 2-keto decarboxylase (KDC) gene, which enabled the production and secretion of isobutyric acid (IBA).

Semiquinone intermediates are involved in the energy coupling mechanism of E. coli complex I.

Complex I (NADH:quinone oxidoreductase) is central to cellular aerobic energy metabolism, and its deficiency is involved in many human mitochondrial diseases. Complex I translocates protons across the membrane using electron transfer energy. Semiquinone (SQ) intermediates appearing during catalysis are suggested to be key for the coupling mechanism in complex I.