The ideal plant for cultivation in space would provide as many nutrients from as few inputs as possible. Here, we discuss how biotechnology could be used to produce a potato cultivar suitable for ...humans in space.The logistical and practical challenges of supplying food for long-term space missions are substantial. In this comment, the authors discuss potential biotechnological approaches that could be used to aid the production of food crops in space.
Humans have been committed to space exploration and to find the next planet suitable for human survival. The construction of an ecosystem that adapts to the long-term survival of human beings in ...space stations or other planets would be the first step. The space plant cultivation system is the key component of an ecosystem, which will produce food, fiber, edible oil and oxygen for future space inhabitants. Many plant experiments have been carried out under a stimulated or real environment of altered gravity, including at microgravity (0 g), Moon gravity (0.17 g) and Mars gravity (0.38 g). How plants sense gravity and change under stress environment of altered gravity were summarized in this review. However, many challenges remain regarding human missions to the Moon or Mars. Our group conducted the first plant experiment under real Moon gravity (0.17 g) in 2019. One of the cotton seeds successfully germinated and produced a green seedling, which represents the first green leaf produced by mankind on the Moon.
Pot experiments were conducted to investigate the impacts of continuous addition of different concentrations of calcium chloride (CaCl2) and/or low-molecular-weight organic acids (LMWOAs) on soil pH, ...electrical conductivity (EC), and cadmium (Cd) transformation. These factors subsequently affected Cd phytoavailability in a system consisting of Cd-contaminated soil and Chinese cabbage (Brassica chinensis L.). The results indicate that CaCl2 addition had a greater impact on reducing soil pH value, increasing soil EC value, and enhancing Cd phytoaccumulation in Chinese cabbage compared to LMWOAs. When soil pH dropped by 0.3 unit and the soil EC increased by 500 µS cm−1, the Cd concentration in the Chinese cabbage shoots was 3 times higher than that in the control group. Throughout two planting terms of Chinese cabbage, the addition of CaCl2 (1.6–3.2 g kg−1) and LMWOAs (≤ 1.0 g kg−1) led to phytoextracted Cd concentration exceeding exchangeable Cd concentration in soil samples before the pot experiment. Regarding phytoextracted Cd, desorption from carbonate-bound Cd contributes more than desorption from bound to organic matter Cd and adsorption to Fe/Mn oxide Cd. This study underscores the influence of soil pH and EC value variations and Cd transformation on Cd phytoavailability. Special attention should be given to leafy vegetables grown in Cd-contaminated soil, as the phytoavailable Cd concentration reaches approximately 2.0 µg kg−1, which may lead to Cd levels surpassing acceptable limits for Chinese cabbage.
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•Soil pH fell by 0.3 and EC rose by 0.5 dS m− 1 causing 3 times of CCd in Chinese cabbage.•Cd transformation between Cd fractions affects the phytoextracted Cd from soil.•Phytoavailable of CCd at 2.0 µg kg− 1 in soil may lead to 0.2 mg kg− 1 of CCd in Chinese cabbage.•Soil Cd threshold for food safety should be re-established based on phytoavailable Cd.
► A new laccase immobilized system was built using magnetic bimodal mesoporous carbon. ► Immobilized laccase exhibited excellent adsorption capacity and activity recovery. ► Immobilization improved ...reusability and resistance to pH and temperature changes. ► Nearly 80% of phenols were removed by the immobilized laccase in 12h. ► Adsorption effects of the support mainly contributed to the first hour of removal.
A novel magnetically separable laccase immobilized system was constructed by adsorbing laccase into bimodal carbon-based mesoporous magnetic composites (CMMC). A large adsorption capacity (491.7mgg−1), excellent activity recovery (91.0%) and broader pH and temperature profiles than free laccase have been exhibited by the immobilized laccase. Thermal stability was enhanced to a great extent and operational stability was increased to a certain extent. The shift of kinetic parameters indicated affinity change between enzyme and substrate. Application of the immobilized system in phenol and p-chlorophenol removal was investigated in a batch system. Adsorption effects of the support were responsible for the quick removal rate in the first hour, and up to 78% and 84% of phenol and p-chlorophenol were removed in the end of the reaction, respectively, indicating that the magnetic bimodal mesoporous carbon is a promising carrier for both immobilization of laccase and further application in phenol removal.
The aim of this study is to develop a polyethylenimine (PEI) grafted magnetic porous adsorbent for highly effective adsorption of heavy metals. The process of grafting PEI was confirmed by Fourier ...transform infrared (FTIR) analysis. Batch tests were carried out to investigate the adsorption performance. Adsorption of Cu2+, Zn2+ and Cd2+ was dependent on pH and increasing the pH was favorable to metal ions removal. The adsorption equilibrium was reached within 10min and well described by pseudo-second-order model. The sorption isotherms of the adsorbent for these metals fitted well with Langmuir model, with maximum adsorption capacities of 157.8, 138.8 and 105.2mg/g for Cu2+, Zn2+ and Cd2+, respectively. Competitive adsorption among the three metal ions showed a preferential adsorption of Cu2+>Zn2+>Cd2+. The magnetic adsorbent exhibited excellent acid–alkali stability. In addition, the exhausted adsorbent can be regenerated by 0.02mol/L EDTA solution without significant adsorption capacity loss.
►A PEI-grafted magnetic porous adsorbent is developed for removal of heavy metals.►The adsorbent possesses excellent acid alkali stability, time stability, that can be used repeatedly. ►Adsorption of Cu2+, Zn2+ and Cd2+ reaches equilibrium in 10min. ►The maximum adsorption capacity is up to 157.81, 138.84 and 105.26mg/g for Cu2+, Zn2+ and Cd2+. ► The PEI-grafted magnetic porous adsorbent has potential application in waste water treatment.
Exploring the relative contribution of spatial factors and environmental variables in shaping communities is of widespread interest in biodiversity conservation and environmental management. Stream ...communities are hierarchically regulated by environmental variables over multiple spatial scales, and the reaction of different organisms to stressors are still equivocal. We sampled both macroinvertebrates and diatom at 80 sites and additional 10 sites for macroinvertebrates, field measured and laboratory analyzed environmental variables, from the tributaries of Qiantang River, Yangtze River Delta China in 2011. We used PCNM (principal coordinates of neighbor matrices) to generate spatial predictors. We applied redundancy analysis and variation partitioning procedures to identify key spatial and environmental factors, and to quantify their relative roles in shaping diatom and macroinvertebrate assemblages. Our results demonstrated the role of spatial and environmental variables differed in shaping benthic diatom and macroinvertebrate. Diatom assemblage variations were better explained by spatial factors, however macroinvertebrate assemblage variations were better explained by environmental variables. In terms of environmental variables, catchment scale variables (e.g., land use estimators, land use diversity) played the primary role in determining the patterns of both diatom and macroinvertebrate assemblages, whereas the influence of reach-scale variables (e.g., pH, substrates, and nutrients) appeared less. However, nutrients were the stronger factors influencing benthic diatom, whereas physical habitat (e.g., substrates) played more important role than water chemistry in structuring macroinvertebrates. Our results provided more evidence to the incorporation of spatial factors interpreting spatial patterns of stream organisms, and highlighted the useful of multiple organisms and environmental variables at different spatial scales in diagnosing mechanism of stream degradation and in building a sound stream conditions monitoring program for Yangtze River Delta.
Target of Rapamycin (TOR) signaling is an important regulator in multiple organisms including yeast, plants, and animals. However, the TOR signaling in plants is much less understood as compared to ...that in yeast and animals. TOR kinase can be efficiently suppressed by rapamycin in the presence of functional FK506 Binding Protein 12 KD (FKBP12) in yeast and animals. In most examined higher plants rapamycin fails to inhibit TOR kinase due to the non-functional FKBP12. Here we find that tomato plants showed obvious growth inhibition when treated with rapamycin and the inhibitory phenotype is similar to suppression of TOR causing by active-site TOR inhibitors (asTORis) such as KU63794, AZD8055, and Torin1. The chemical genetic assays using TOR inhibitors and heterologous expressing SlFKBP12 in
indicated that the TOR signaling is functional in tomato. The protein gel shifting and TOR inhibitors combination assays showed that SlFKBP12 can mediate the interaction between rapamycin and TOR. Furthermore, comparative expression profile analysis between treatments with rapamycin and KU63794 identified highly overlapped Differentially Expressed Genes (DEGs) which are involved in many anabolic and catabolic processes, such as photosynthesis, cell wall restructuring, and senescence in tomato. These observations suggest that SlFFBP12 is functional in tomato. The results provided basic information of TOR signaling in tomato, and also some new insights into how TOR controls plant growth and development through reprogramming the transcription profiles.
Previous works have demonstrated that ligninolytic enzymes mediated effective degradation of lignin wastes. The degrading ability greatly relied on the interactions of ligninolytic enzymes with ...lignin. Ligninolytic enzymes mainly contain laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP). In the present study, the binding modes of lignin to Lac, LiP and MnP were systematically determined, respectively. Robustness of these modes was further verified by molecular dynamics (MD) simulations. Residues GLU460, PRO346 and SER113 in Lac, residues ARG43, ALA180 and ASP183 in LiP and residues ARG42, HIS173 and ARG177 in MnP were most crucial in binding of lignin, respectively. Interactional analyses showed hydrophobic contacts were most abundant, playing an important role in the determination of substrate specificity. This information is an important contribution to the details of enzyme-catalyzed reactions in the process of lignin biodegradation, which can be used as references for designing enzyme mutants with a better lignin-degrading activity.
Over the past decades, numerous studies have been carried out in understanding causes of Harmful Algal Blooms (HABs) and their dynamics, yielding great knowledge in this field. Lake Erie, the ...fourth-largest lake of the five Great Lake, is among those highly vulnerable to the impacts of HABs and has received substantial attention from the public, water management sectors, and academic field. Building upon previous work, this study aims to characterize spatiotemporal variability of Chlorophyll a (Chl-a), which is an important indicator of HABs, and to explore relative importance of environmental factors associated with HABs in the west Lake Erie. Ten years of biweekly Chl-a information over western Lake Erie were derived from MERIS data at the pixel scale. Based on the MERIS-derived information high concentrations of Chl-a were observed in the south near shore area in spring and fall and in the west corner area of western Lake Erie in all three seasons except winter. Wavelet analysis suggested that the 0.5- and 1-year periods were dominant modes for the Chl-a series. The Multivariate Adaptive Regression Splines (MARS) analysis was performed to explore factors associated with the dynamics of Chl-a. The results suggested that overall both phenological (e.g. wind) and ecological (e.g. nutrient levels) factors exhibited significant correlations with the remotely-sensed imagery based observations of Chl-a despite spatial and temporal variations. The important phenological and ecological factors include solar radiation and wind speed in spring, water temperature, solar radiation, and total Kjeldahl nitrogen concentration in summer, wind speed in fall, and water temperature and streamflow in winter. Both consistency and differences of findings of the study with others in the region may suggest strengths and limitations of the remotely sensed imagery-based analysis, offering valuable information for future work.
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