Article
Biochemistry & Molecular Biology
Andrew R. Popchock, Joshua D. Larson, Julien Dubrulle, Charles L. Asbury, Sue Biggins
Summary: Eukaryotic chromosome segregation requires a large machine called the kinetochore, which contains CENP-A and is responsible for nucleosome formation. This study investigates the functions of the chaperone protein HJURP in CENP-A deposition and the conservation of high AT DNA content at centromeres. Through a microscopy assay, it is found that CENP-A can arrive at centromeres without HJURP but stable incorporation requires HJURP and other DNA-binding proteins. Homopolymer AT runs in yeast centromeres are also essential for efficient CENP-A deposition. These findings provide insights into nucleosome formation and lay the foundation for future studies on kinetochore complexes.
Article
Environmental Sciences
Wenhui An, Chuan Wu, Shengguo Xue, Ziyu Liu, Min Liu, Waichin Li
Summary: This study investigates the effects of biochar and AQDS on the transformation and migration of As and Fe. The results show that under abiogenic conditions, both biochar and AQDS promote the reduction of Fe and release of As. AQDS has a better electron shuttle function compared to biochar. However, in the presence of Shewanella oneidensis MR-1, biochar promotes a higher release of As and the formation of secondary minerals.
Article
Engineering, Environmental
Juan Liu, Anxu Sheng, Xiaoxu Li, Yuji Arai, Yuefei Ding, Mingjun Nie, Mingquan Yan, Kevin M. Rosso
Summary: The transformation of metastable Fe(III) oxyhydroxides is an important process in natural environments, which can be accelerated by the presence of Fe(II). Recent evidence suggests that the solution mass transfer of labile Fe(III) is a key intermediate species. However, the dependency of phase outcomes on the identity of the metastable Fe(III) oxyhydroxide precursor is unclear. In this study, we compared the transformation of lepidocrocite and ferrihydrite and found that different precursors lead to different products. These findings enhance our understanding of factors that affect iron bioavailability, system redox potential, and the fate and transport of coupled elements.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Hui Wang, Jia Zhang, Jinqi Zhu, Jingjie Chang, Ning Wang, Honghan Chen
Summary: This study investigated the synergistic/antagonistic effects of Fe(III)-humic acid coprecipitates on the adsorption and reduction of Cr(VI) in soils. The results showed that increasing proportions of humic acid led to stronger antagonistic effects on Cr(VI) adsorption, while significant synergistic reduction effects were found in certain coprecipitates.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
Girish Choppala, Dane Lamb, Robert Aughterson, Edward D. Burton
Summary: Tooeleite is an important As(III) host phase in mining-impacted environments and has received attention for immobilizing As(III) in environmental and engineered settings. The study shows that environmentally relevant concentrations of aqueous Fe(II) can significantly mobilize As(III) from Tooeleite into the aqueous phase, particularly under near-neutral pH conditions.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Andreas Fritzsche, Julian Bosch, Michael Sander, Christian Schroder, James M. Byrne, Thomas Ritschel, Prachi Joshi, Markus Maisch, Rainer U. Meckenstock, Andreas Kappler, Kai U. Totsche
Summary: In redoximorphic soils, microbial reduction of iron (III) minerals is significantly influenced by organic matter, which can either decelerate or accelerate the reduction rate. The organic matter released by microbial activity under anaerobic conditions (efOM) plays a key role in affecting the electron uptake and crystallinity of iron (III) minerals. The presence of efOM, whether adsorbed or coprecipitated, leads to distinct effects on microbial reduction of iron (III) minerals by affecting the surface passivation and altering the mineral structure.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Geochemistry & Geophysics
Anxu Sheng, Juan Liu, Xiaoxu Li, Langli Luo, Yuefei Ding, Chunmei Chen, Xin Zhang, Chongmin Wang, Kevin M. Rosso
Summary: The study investigated the transformation of Fe(II)-catalyzed Fh to more crystalline iron (oxyhydr)oxide phases, finding that the kinetics and properties of the product phases depend primarily on the rate of accumulation of the labile Fe(III) precursor to its critical concentration.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Microbiology
Elizabeth C. Sklute, Deborah A. Leopo, Kaylee A. Neat, Kenneth J. T. Livi, M. Darby Dyar, James F. Holden
Summary: This study investigates the biogenic mineral transformation of thermophilic bacteria Desulfovulcanus ferrireducens on various types of Fe(III) minerals. The results demonstrate that these bacteria can catalyze dissolution-reprecipitation reactions on different Fe(III) minerals, leading to the formation of diverse mineral products.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Engineering, Environmental
Junshu Chen, Hao Yan, Haifeng Gong, Hexuan Zhang, Yixuan Zhou, Chenyang Gao, Yibin Liu, Xiaobo Chen, Chaohe Yang
Summary: Reasonable regulation of acidity in ZSM-5 catalysts, by introducing highly dispersed tetrahedrally coordinated W(VI) species, greatly improves the catalytic cracking performance for the production of propene from 1-hexene. The introduction of W enhances the stability of the catalyst structure, eliminates non-skeleton aluminum and excessive Bronsted acid sites, and inhibits carbon/coke deposition. The active tetrahedrally coordinated W(VI) species also enhance propene selectivity by inhibiting product polymerization. Optimizing parameters such as Si/Al ratio, temperature, and weight hourly space velocity allows for high conversion and selectivity to be maintained over a long reaction period.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Physics, Multidisciplinary
Y. S. Lin, S. Y. Wang, X. Zhang, Y. Feng, Y. P. Pan, H. Ru, J. J. Zhu, B. K. Xiang, K. Liu, C. L. Zheng, L. Y. Wei, M. X. Wang, Z. K. Liu, L. Chen, K. Jiang, Y. F. Guo, Ziqiang Wang, Y. H. Wang
Summary: Vortices are topological defects that can appear in type-II superconductors even in the absence of an external magnetic field. In this study, the researchers used scanning superconducting quantum interference device microscopy to search for quantum anomalous vortices in an iron-chalcogenide superconductor. They found a stochastic distribution of isolated anomalous vortices and antivortices, and observed hysteretic flipping and vectorial rotation of these vortices with the application of a small local magnetic field. These unique properties satisfy the defining criteria of quantum anomalous vortices, suggesting an emergent quantum phase in the superconductor with nontrivial topological band structure.
Article
Engineering, Environmental
Astolfo Valero, Jiri Jan, Daniel A. A. Petrash
Summary: This study demonstrates the efficient removal of arsenite from water using a bioelectrochemical system (BES) with the help of redox reactive humic substances derivatives and reactive nitrogen species. Geobacter sp. utilizes humic derivatives as electron shuttles, facilitating the reduction of Fe(iii) and the scavenging of As(iii). These findings contribute to the development of effective BESs for arsenite removal.
ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Qian Yao, Limiao Cai, Xiaofei Li, Xiaohu Jin, Guining Lu, Chuling Guo, Weilin Huang, Zhi Dang, Xiaoyun Yi
Summary: It has been reported that Fe(ii)-catalyzed Fe-bearing minerals play a role in the redistribution of heavy metals and phase transition of minerals in acid mine drainage (AMD) environments. However, the effects and mechanisms of interactions among organic acids, Fe(ii), and Fe oxide minerals on heavy metal fate under different pH conditions are still not well understood. In this study, oxalic acid (OA) was used as a surrogate to investigate the influence of OA on the transformation of Fe(ii)-induced Cr(iii)-bearing schwertmannite (Cr-Sch) and Cr/C redistribution at pH 3.5-7.0. The results showed that the presence of Fe(ii) decreased the overall relative intensity of OA adsorption on the mineral surface and increased the proportion of a bidentate binuclear complex (BB). The binding mode of the BB and a bidentate mononuclear complex decreased with increasing pH. However, regardless of the presence of Fe(ii), the dominance gradually shifted to an outer-sphere complex (OS) and aqueous oxalate (Ox) ions. The study also found that OA was adsorbed on the goethite surface and Cr was mostly in an aqueous and extractable state in the presence of Ox. The synergy of OA and Fe(ii) accelerated mineral dissolution but impeded Fe(iii) recrystallization at pH > 5.5, leading to a direct transformation from schwertmannite to goethite. This study provides new insights into the transformation of Cr-Sch and the fate of Cr(iii) under the coexistence of Fe(ii) and OA in an AMD environment, particularly in a watershed that has experienced significant pH changes.
ENVIRONMENTAL SCIENCE-NANO
(2023)
Article
Chemistry, Physical
Sharmistha De Dalui, Bidisa Das
Summary: Fe(III) oxides and oxyhydroxides, due to their nanoparticulate nature, play a crucial role in contaminant cycling and mobility in the environment through various sorption mechanisms. Doping of impurity ions, such as aluminum (Al), into Fe(III) oxyhydroxide nanoparticles modifies their adsorption energetics, affecting the binding potential of toxic contaminants like arsenic (As). Our electronic structure studies demonstrate that Al doping reduces the As binding potential of Fe(III) oxyhydroxide clusters for As3+, while it has minimal effect on As5+ binding.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Trinh Thi Ly, Jungmin Park, Kyoo Kim, Hyo-Bin Ahn, Nyun Jong Lee, Kwangsu Kim, Tae-Eon Park, Ganbat Duvjir, Nguyen Huu Lam, Kyuha Jang, Chun-Yeol You, Younghun Jo, Se Kwon Kim, Changgu Lee, Sanghoon Kim, Jungdae Kim
Summary: This study investigates the microscopic structures and magnetic properties of Fe5-xGeTe2 single crystal, a promising van der Waals ferromagnet, revealing the root 3 x root 3 superstructures possibly leading to helical magnetism. The non-centrosymmetricity originating from the unique Fe atom ordering contributes to the understanding of the material's magnetic behavior.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Geochemistry & Geophysics
Fatima Meite, Thomas Hauet, Patrick Billard, Tom Ferte, Mustapha Abdelmoula, Asfaw Zegeye
Summary: Anthropogenic activities have resulted in the accumulation of Pb in the environment, posing a threat to ecosystems. This study investigates the impact of Pb on the bioreduction and transformation processes of iron oxides, which play a crucial role in controlling the environmental fate of Pb. The findings highlight the sensitivity of magnetism as a monitoring method and provide insights into the behavior of Pb in the presence of iron-reducing bacteria.
