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•MnOx@Pal adsorbent was successfully synthesized.•Fluoroquinolones (FQs) could be adsorption by MnOx@Pal.•Adsorption kinetics, adsorption thermodynamics and adsorption isotherm were ...explored.•The influencing factors of adsorption and desorption agent were explored.•The adsorption mechanism of MnOx@Pal was elucidated.
Adsorption plays a critical role in eliminating antibiotics in wastewater, so it is urgent to develop an effective adsorbent in the application. Palygorskite exhibits enormous potential in the field of adsorption. In this study, palygorskite was modified by MnOx into a suitable and efficient adsorbent by a simple method, and they were used for the application and comparison of adsorbing fluoroquinolone antibiotics from aqueous solution. The surface chemical properties of adsorbents were characterized by different analytical techniques, and the results were used to analyze the corresponding adsorption interactions. Statistical physics calculations were performed to explain the physical and chemical parameters involved in FQs adsorption mechanism. The highest adsorption efficiency was achieved at pH 3, and the maximum adsorption capacities of MnOx@Pal for CIP, ENR, LFX and LOM were 51.48 mg·g−1, 40.46 mg·g−1, 55.16 mg·g−1 and 52.13 mg·g−1, respectively. Antibiotics adsorption mechanism of adsorbent is mainly due to electrostatic interaction and hydrogen bonding. The adsorbent can be desorbed more easily using NaOH solutions. This adsorbent is expected to be used to treat wastewater contaminated by fluoroquinolone antibiotics.
The protein Pal (peptidoglycan-associated lipoprotein) is anchored in the outer membrane (OM) of Gram-negative bacteria and interacts with Tol proteins. Tol-Pal proteins form two complexes: the first ...is composed of three inner membrane Tol proteins (TolA, TolQ and TolR); the second consists of the TolB and Pal proteins linked to the cell's OM. These complexes interact with one another forming a multiprotein membrane-spanning system. It has recently been demonstrated that Pal is essential for bacterial survival and pathogenesis, although its role in virulence has not been clearly defined. This review summarizes the available data concerning the structure and function of Pal and its role in pathogenesis.
Microplastics (MPs), recognized as significant emerging contaminants, are prevalent in both terrestrial and aquatic ecosystems. This study investigates the potential of biochar derived from Polygonum ...amphibium L. (PAL) sourced from Taihu Lake and processed through a low-temperature carbonization method, for in the removal of MPs. This approach addresses the escalating presence of MPs in aqueous environment, especially during the COVID-19 pandemic, simultaneously tackles the issue of waste biomass contributing to eutrophication. The study focused on the impact of carbonization temperatures (450℃-550℃) on physicochemical properties of biochar. Additionally, the effect of contact time, initial concentration of MPs, and environmental factors at various carbonization temperatures were also examined. The results reveal that the biochar yield and adsorption performance of biochar are significantly influenced by carbonization temperature. The adsorption capacity of biochar for MPs removal increases with the carbonization temperature up to 500 ℃, attributed to enhanced diffusion, surface adsorption, interactions, and cation-π electron interactions between the biochar and MPs. However, at a pyrolysis temperature of 550 ℃, the increase in adsorption capacity of biochar-550 is marginal due to increased competitive binging and destabilization of biochar under basic conditions. Overall, the optimum carbonization temperature is identified as 500 ℃, yielding a char rate is 32.23% and an adsorption capacity for MPs of 80.3 mg/g, thereby offering a promising solution for MP removal and water eutrophication management.
The physiology of bacterial cell division Egan, Alexander J. F.; Vollmer, Waldemar
Annals of the New York Academy of Sciences,
January 2013, Letnik:
1277, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Bacterial cell division is facilitated by the divisome, a dynamic multiprotein assembly localizing at mid‐cell to synthesize the stress‐bearing peptidoglycan and to constrict all cell envelope ...layers. Divisome assembly occurs in two steps and involves multiple interactions between more than 20 essential and accessory cell division proteins. Well before constriction and while the cell is still elongating, the tubulin‐like FtsZ and early cell division proteins form a ring‐like structure at mid‐cell. Cell division starts once certain peptidoglycan enzymes and their activators have moved to the FtsZ‐ring. Gram‐negative bacteria like Escherichia coli simultaneously synthesize and cleave the septum peptidoglycan during division leading to a constriction. The outer membrane constricts together with the peptidoglycan layer with the help of the transenvelope spanning Tol–Pal system.
Phenylalanine ammonia-lyase is one of the most widely studied enzymes in the plant kingdom. It is a crucial pathway from primary metabolism to significant secondary phenylpropanoid metabolism in ...plants, and plays an essential role in plant growth, development, and stress defense. Although PAL has been studied in many actual plants, only one report has been reported on potato, one of the five primary staple foods in the world. In this study, 14 StPAL genes were identified in potato for the first time using a genome-wide bioinformatics analysis, and the expression patterns of these genes were further investigated using qRT-PCR. The results showed that the expressions of StPAL1, StPAL6, StPAL8, StPAL12, and StPAL13 were significantly up-regulated under drought and high temperature stress, indicating that they may be involved in the stress defense of potato against high temperature and drought. The expressions of StPAL1, StPAL2, and StPAL6 were significantly up-regulated after MeJa hormone treatment, indicating that these genes are involved in potato chemical defense mechanisms. These three stresses significantly inhibited the expression of StPAL7, StPAL10, and StPAL11, again proving that PAL is a multifunctional gene family, which may give plants resistance to multiple and different stresses. In the future, people may improve critical agronomic traits of crops by introducing other PAL genes. This study aims to deepen the understanding of the versatility of the PAL gene family and provide a valuable reference for further genetic improvement of the potato.
The Pohang Accelerator Laboratory X‐ray Free‐Electron Laser (PAL‐XFEL) is a recently commissioned X‐ray free‐electron laser (XFEL) facility that provides intense ultrashort X‐ray pulses based on the ...self‐amplified spontaneous emission process. The nano‐crystallography and coherent imaging (NCI) hutch with forward‐scattering geometry is located at the hard X‐ray beamline of the PAL‐XFEL and provides opportunities to perform serial femtosecond crystallography and coherent X‐ray diffraction imaging. To produce intense high‐density XFEL pulses at the interaction positions between the X‐rays and various samples, a microfocusing Kirkpatrick–Baez (KB) mirror system that includes an ultra‐precision manipulator has been developed. In this paper, the design of a KB mirror system that focuses the hard XFEL beam onto a fixed sample point of the NCI hutch, which is positioned along the hard XFEL beamline, is described. The focusing system produces a two‐dimensional focusing beam at approximately 2 µm scale across the 2–11 keV photon energy range. XFEL pulses of 9.7 keV energy were successfully focused onto an area of size 1.94 µm × 2.08 µm FWHM.
Microfocusing of hard X‐ray free‐electron laser pulses using Kirkpatrick–Baez mirrors at the nano‐crystallography and coherent imaging hutch of the Pohang Accelerator Laboratory X‐ray Free‐Electron Laser facility is reported.
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•Co/In–MOF@PAL was used as a precursor for preparation of In2O3/Co3O4@PAL catalyst.•In2O3/Co3O4@PAL has good catalytic activity to degrade MB (TC) under solar light.•Its MB (TC) ...degradation rate reached 99% (80%) compared to 15% (40%) for In2O3/Co3O4.•The O2−, HO and h+ radicals participated in the decomposition of MB and TC.
A facile method for fabrication of In2O3/Co3O4@palygorskite composites from a Co/In-based metal-organic framework (MOF) was reported. First, Co/In-MOFs hybridized with palygorskite (PAL) was prepared via a one-pot solvothermal method. Second, In2O3/Co3O4@PAL composites were obtained by pyrolysis of In2O3/Co3O4@PAL in air. It was found that the In2O3/Co3O4@PAL composite exhibited higher photocatalytic activities than In2O3/Co3O4 to the degradation of MB and TC under visible-light irradiation. About 99% of MB (within 40min) and 80% of TC (within 120min) were degraded using In2O3/Co3O4@5.0%PAL as catalyst. It was supposed that the efficient adsorption of MB and TC, and electrostatic interactions between electron–hole and PAL were responsible for such improvement. The photocatalytic degradation mechanisms of MB and TC on the In2O3/Co3O4@PAL were investigated. This work shows that hybridization MOFs with PAL could enhance the photocatalytic properties of MOFs-derived metal oxides for water treatment.
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