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Jiang X, Jia X, Gao S, Jiang Y, Wei N, Han C, Zha T, Liu P, Tian Y, Qin S. Plant Nutrient Contents Rather Than Physical Traits Are Coordinated Between Leaves and Roots in a Desert Shrubland. Front Plant Sci 2021; 12:734775. [PMID: 34764966 PMCID: PMC8576145 DOI: 10.3389/fpls.2021.734775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/28/2021] [Indexed: 06/12/2023]
Abstract
Although leaf economics spectrum (LES) has been extensively tested with regional and global datasets, the correlation among functional traits of desert plants remains largely unclear. Moreover, examinations on whether and how leaf and root traits are coordinated have yielded mixed results. We investigated variations in leaf and fine-root traits across 48 species in a desert community of northern China to test the hypotheses that (1) the leaf-trait syndrome of plant species in desert shrublands follows the predictions of the global LES, and is paralleled by a similar root-trait syndrome, (2) functional traits related to nutrient contents and resource uptake are tightly coordinated between leaves and fine roots in desert ecosystems where plant growth is limited primarily by dry and nutrient-poor conditions, and (3) traits as well as their relationships vary among functional groups. Our results partially supported the LES theory. Specific leaf area (SLA) was correlated with leaf tissue density, phosphorus content, and carbon-to-nitrogen ratio, but not with leaf nitrogen content. Specific root length (SRL) was not correlated with other fine-root traits, and fine-root traits were largely independent of each other. Therefore, fine-root traits did not mirror the leaf-trait syndrome. Fine-root nitrogen and phosphorus contents, nitrogen-to-phosphorous ratio, and carbon-to-nitrogen ratio all increased with analogous leaf traits, whereas SRL was not correlated with SLA. After phylogenetic effects were considered, nutrient contents and their ratios still displayed stronger coordination between leaves and fine roots than did SRL and SLA. The overall pattern of trait variations and relationships suggested differentiation among functional groups. Our results suggest that despite the absence of a root-trait syndrome, fine-root functions in the studied desert community were probably coordinated with leaf functions with respect to nutrient allocation and use.
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Affiliation(s)
- Xiaoyan Jiang
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Xin Jia
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory for Soil and Water Conservation, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Shengjie Gao
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Yan Jiang
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Ningning Wei
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Cong Han
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Tianshan Zha
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory for Soil and Water Conservation, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Peng Liu
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory for Soil and Water Conservation, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Yun Tian
- Key Laboratory for Soil and Water Conservation, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Shugao Qin
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory for Soil and Water Conservation, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
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102
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Yang Z, Zhan W, Jiang L, Chen H. Effect of Short-Term Low-Nitrogen Addition on Carbon, Nitrogen and Phosphorus of Vegetation-Soil in Alpine Meadow. Int J Environ Res Public Health 2021; 18:10998. [PMID: 34682742 DOI: 10.3390/ijerph182010998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/11/2021] [Accepted: 10/15/2021] [Indexed: 12/05/2022]
Abstract
As one of the nitrogen (N) limitation ecosystems, alpine meadows have significant effects on their structure and function. However, research on the response and linkage of vegetation-soil to short-term low-level N deposition with rhizosphere processes is scant. We conducted a four level N addition (0, 20, 40, and 80 kg N ha−1 y−1) field experiment in an alpine meadow on the Qinghai-Tibetan Plateau (QTP) from July 2014 to August 2016. We analyzed the community characteristics, vegetation (shoots and roots), total carbon (TC), nutrients, soil (rhizosphere and bulk) properties, and the linkage between vegetation and soil under different N addition rates. Our results showed that (i) N addition significantly increased and decreased the concentration of soil nitrate nitrogen (NO3−-N) and ammonium nitrogen, and the soil pH, respectively; (ii) there were significant correlations between soil (rhizosphere and bulk) NO3−-N and total nitrogen (TN), and root TN, and there was no strong correlation between plant and soil TC, TN and total phosphorus, and their stoichiometry under different N addition rates. The results suggest that short-term low-N addition affected the plant community, vegetation, and soil TC, TN, TP, and their stoichiometry insignificantly, and that the correlation between plant and soil TC, TN, and TP, and their stoichiometry were insignificant.
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103
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Ansari F, Yoval-Sánchez B, Niatsetskaya Z, Sosunov S, Stepanova A, Garcia C, Owusu-Ansah E, Ten V, Wittig I, Galkin A. Quantification of NADH:ubiquinone oxidoreductase (complex I) content in biological samples. J Biol Chem 2021; 297:101204. [PMID: 34543622 PMCID: PMC8503622 DOI: 10.1016/j.jbc.2021.101204] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/26/2021] [Accepted: 08/31/2021] [Indexed: 12/14/2022] Open
Abstract
Impairments in mitochondrial energy metabolism have been implicated in human genetic diseases associated with mitochondrial and nuclear DNA mutations, neurodegenerative and cardiovascular disorders, diabetes, and aging. Alteration in mitochondrial complex I structure and activity has been shown to play a key role in Parkinson's disease and ischemia/reperfusion tissue injury, but significant difficulty remains in assessing the content of this enzyme complex in a given sample. The present study introduces a new method utilizing native polyacrylamide gel electrophoresis in combination with flavin fluorescence scanning to measure the absolute content of complex I, as well as α-ketoglutarate dehydrogenase complex, in any preparation. We show that complex I content is 19 ± 1 pmol/mg of protein in the brain mitochondria, whereas varies up to 10-fold in different mouse tissues. Together with the measurements of NADH-dependent specific activity, our method also allows accurate determination of complex I catalytic turnover, which was calculated as 104 min-1 for NADH:ubiquinone reductase in mouse brain mitochondrial preparations. α-ketoglutarate dehydrogenase complex content was determined to be 65 ± 5 and 123 ± 9 pmol/mg protein for mouse brain and bovine heart mitochondria, respectively. Our approach can also be extended to cultured cells, and we demonstrated that about 90 × 103 complex I molecules are present in a single human embryonic kidney 293 cell. The ability to determine complex I content should provide a valuable tool to investigate the enzyme status in samples after in vivo treatment in mutant organisms, cells in culture, or human biopsies.
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Affiliation(s)
- Fariha Ansari
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Belem Yoval-Sánchez
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Zoya Niatsetskaya
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Sergey Sosunov
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Anna Stepanova
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Christian Garcia
- Department of Physiology & Cellular Biophysics, Columbia University, New York, New York, USA
| | - Edward Owusu-Ansah
- Department of Physiology & Cellular Biophysics, Columbia University, New York, New York, USA
| | - Vadim Ten
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Ilka Wittig
- Functional Proteomics, Institute of Cardiovascular Physiology, Goethe University, Frankfurt am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner site RheinMain, Frankfurt am Main, Germany
| | - Alexander Galkin
- Division of Neonatology, Department of Pediatrics, Columbia University Medical Center, New York, New York, USA; Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York, USA.
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104
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Biagioni F, Mastroiacovo F, Lenzi P, Puglisi-Allegra S, Busceti CL, Ryskalin L, Ferese R, Bucci D, Frati A, Nicoletti F, Fornai F. The Autophagy-Related Organelle Autophagoproteasome Is Suppressed within Ischemic Penumbra. Int J Mol Sci 2021; 22:10364. [PMID: 34638703 DOI: 10.3390/ijms221910364] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 01/18/2023] Open
Abstract
The peri-infarct region, which surrounds the irreversible ischemic stroke area is named ischemic penumbra. This term emphasizes the borderline conditions for neurons placed within such a critical region. Area penumbra separates the ischemic core, where frank cell loss occurs, from the surrounding healthy brain tissue. Within such a brain region, nervous matter, and mostly neurons are impaired concerning metabolic conditions. The classic biochemical marker, which reliably marks area penumbra is the over-expression of the heat shock protein 70 (HSP70). However, other proteins related to cell clearing pathways are modified within area penumbra. Among these, autophagy proteins like LC3 increase in a way, which recapitulates Hsp70. In contrast, components, such as P20S, markedly decrease. Despite apparent discrepancies, the present study indicates remarkable overlapping between LC3 and P20S redistribution within area penumbra. In fact, the amount of both proteins is markedly reduced within vacuoles. Specifically, a massive loss of LC3 + P20S immuno-positive vacuoles (autophagoproteasomes) is reported here. This represents the most relevant sub-cellular alteration here described in cell clearing pathways within area penumbra. The functional significance of these findings remains to be determined and it will take a novel experimental stream to decipher the fine-tuning of such a phenomenon.
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105
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Salavessa L, Lagache T, Malardé V, Grassart A, Olivo-Marin JC, Canette A, Trichet M, Sansonetti PJ, Sauvonnet N. Cytokine receptor cluster size impacts its endocytosis and signaling. Proc Natl Acad Sci U S A 2021; 118:e2024893118. [PMID: 34504012 DOI: 10.1073/pnas.2024893118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2021] [Indexed: 01/08/2023] Open
Abstract
The interleukin-2 receptor (IL-2R) is a cytokine receptor essential for immunity that transduces proliferative signals regulated by its uptake and degradation. IL-2R is a well-known marker of clathrin-independent endocytosis (CIE), a process devoid of any coat protein, raising the question of how the CIE vesicle is generated. Here, we investigated the impact of IL-2Rγ clustering in its endocytosis. Combining total internal reflection fluorescence (TIRF) live imaging of a CRISPR-edited T cell line endogenously expressing IL-2Rγ tagged with green fluorescent protein (GFP), with multichannel imaging, single-molecule tracking, and quantitative analysis, we were able to decipher IL-2Rγ stoichiometry at the plasma membrane in real time. We identified three distinct IL-2Rγ cluster populations. IL-2Rγ is secreted to the cell surface as a preassembled small cluster of three molecules maximum, rapidly diffusing at the plasma membrane. A medium-sized cluster composed of four to six molecules is key for IL-2R internalization and is promoted by interleukin 2 (IL-2) binding, while larger clusters (more than six molecules) are static and inefficiently internalized. Moreover, we identified membrane cholesterol and the branched actin cytoskeleton as key regulators of IL-2Rγ clustering and IL-2-induced signaling. Both cholesterol depletion and Arp2/3 inhibition lead to the assembly of large IL-2Rγ clusters, arising from the stochastic interaction of receptor molecules in close correlation with their enhanced lateral diffusion at the membrane, thus resulting in a default in IL-2R endocytosis. Despite similar clustering outcomes, while cholesterol depletion leads to a sustained IL-2-dependent signaling, Arp2/3 inhibition prevents signal initiation. Taken together, our results reveal the importance of cytokine receptor clustering for CIE initiation and signal transduction.
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106
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Yang S, Shi Z, Zhang M, Li Y, Gao J, Wang X, Liu D. Stoichiometry of Carbon, Nitrogen and Phosphorus in Shrub Organs Linked Closely With Mycorrhizal Strategy in Northern China. Front Plant Sci 2021; 12:687347. [PMID: 34557207 PMCID: PMC8453024 DOI: 10.3389/fpls.2021.687347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 08/18/2021] [Indexed: 05/31/2023]
Abstract
Mycorrhizal strategies include mycorrhizal statuses and mycorrhizal types, which are important reflections of the functional characteristics of ecosystems. The stoichiometry of carbon, nitrogen, and phosphorus in plant organs is an important part of ecosystem functions, which has an important impact on the nutrient cycle of the ecosystem. The concentration of carbon, nitrogen, and phosphorus played a crucial role in ecosystem functioning and dynamics. The purpose of this study is to provide theoretical basis and data support for improving the properties of global terrestrial ecosystems by exploring the impact of mycorrhizal strategies on the stoichiometry of C, N, and P in different shrub organs. In this study, stoichiometric patterns of carbon (C), nitrogen (N) and phosphorus (P) in different shrub organs under different mycorrhizal status or types were analyzed at 725 samples across Northern China. Results showed that in different mycorrhizal status, the highest carbon concentration in shrub organs appeared in the facultatively mycorrhizal (FM) mycorrhizal status, and the highest nitrogen concentration appeared in the Non-mycorrhizal (NM) mycorrhizal status. Under different mycorrhizal types, the nitrogen concentration in the shrub organs under the arbuscular mycorrhiza (AM) mycorrhizal type was the highest, and the phosphorus concentration under the ecto-mycorrhiza (ECM) mycorrhizal type was the highest. In the OM or FM mycorrhizal status, the concentrations of C, N, and P in the stems and leaves increase with the increase of the concentrations of C, N, and P in the roots. In the NM mycorrhizal status, the N concentration in the stems and leaves increases with the increase of the N concentration in the roots. Under AM, AM+ECM, and ECM mycorrhizal type, the concentrations of C, N, and P are closely related in roots, stems and leaves. The content of plant nutrients in different organs is closely related. It turned out that mycorrhizal statuses or types are able to alter the allocation of C, N, and P in different organs, and the relationships of C, N, and P among different organs are able to present different trend with the varying of mycorrhizal statuses or types.
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Affiliation(s)
- Shuang Yang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Zhaoyong Shi
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Menghan Zhang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Yang Li
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Jiakai Gao
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Xugang Wang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
| | - Dehong Liu
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
- Luoyang Key Laboratory of Symbiotic Microorganism and Green Development, Luoyang, China
- Henan Engineering Research Center of Human Settlements, Luoyang, China
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107
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Yin X, Busch FA, Struik PC, Sharkey TD. Evolution of a biochemical model of steady-state photosynthesis. Plant Cell Environ 2021; 44:2811-2837. [PMID: 33872407 PMCID: PMC8453732 DOI: 10.1111/pce.14070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 05/29/2023]
Abstract
On the occasion of the 40th anniversary of the publication of the landmark model by Farquhar, von Caemmerer & Berry on steady-state C3 photosynthesis (known as the "FvCB model"), we review three major further developments of the model. These include: (1) limitation by triose phosphate utilization, (2) alternative electron transport pathways, and (3) photorespiration-associated nitrogen and C1 metabolisms. We discussed the relation of the third extension with the two other extensions, and some equivalent extensions to model C4 photosynthesis. In addition, the FvCB model has been coupled with CO2 -diffusion models. We review how these extensions and integration have broadened the use of the FvCB model in understanding photosynthesis, especially with regard to bioenergetic stoichiometries associated with photosynthetic quantum yields. Based on the new insights, we present caveats in applying the FvCB model. Further research needs are highlighted.
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Affiliation(s)
- Xinyou Yin
- Centre for Crop Systems AnalysisWageningen University & ResearchWageningenThe Netherlands
| | - Florian A. Busch
- School of Biosciences and Birmingham Institute of Forest ResearchUniversity of BirminghamBirminghamUK
| | - Paul C. Struik
- Centre for Crop Systems AnalysisWageningen University & ResearchWageningenThe Netherlands
| | - Thomas D. Sharkey
- MSU‐DOE Plant Research Laboratory, Plant Resilience InstituteMichigan State UniversityEast LansingMichiganUSA
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108
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Yu H, Bai XC, Wang W. Characterization of the subunit composition and structure of adult human glycine receptors. Neuron 2021; 109:2707-2716.e6. [PMID: 34473954 DOI: 10.1016/j.neuron.2021.08.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 07/23/2021] [Accepted: 08/16/2021] [Indexed: 11/27/2022]
Abstract
The strychnine-sensitive pentameric glycine receptor (GlyR) mediates fast inhibitory neurotransmission in the mammalian nervous system. Only heteromeric GlyRs mediate synaptic transmission, as they contain the β subunit that permits clustering at the synapse through its interaction with scaffolding proteins. Here, we show that α2 and β subunits assemble with an unexpected 4:1 stoichiometry to produce GlyR with native electrophysiological properties. We determined structures in multiple functional states at 3.6-3.8 Å resolutions and show how 4:1 stoichiometry is consistent with the structural features of α2β GlyR. Furthermore, we show that one single β subunit in each GlyR gives rise to the characteristic electrophysiological properties of heteromeric GlyR, while more β subunits render GlyR non-conductive. A single β subunit ensures a univalent GlyR-scaffold linkage, which means the scaffold alone regulates the cluster properties.
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Affiliation(s)
- Hailong Yu
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xiao-Chen Bai
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Weiwei Wang
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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109
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Navarro T, Hidalgo-Triana N. Variations in Leaf Traits Modulate Plant Vegetative and Reproductive Phenological Sequencing Across Arid Mediterranean Shrublands. Front Plant Sci 2021; 12:708367. [PMID: 34497623 PMCID: PMC8420881 DOI: 10.3389/fpls.2021.708367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
Structural and nutrient traits of a leaf are important for understanding plant ecological strategies (e.g., drought avoidance). We studied the specific leaf area (SLA), leaf carbon content (LCC), leaf nitrogen content (LNC), leaf phosphorous content (LPC), and the phenophase sequence index (PSI) in 126 Mediterranean perennial species from predesert (SMS) and semiarid (SaMS) to subalpine (SAS), alpine cushion (AcS), and oro-Mediterranean (AjS) shrublands, which represent eight functional groups (evergreen and deciduous trees, evergreen large and half shrubs, deciduous large and half shrubs, succulents and perennial herbs). We analyzed the variation and relationships between leaf traits and PSI among shrublands, functional groups, and within species with drought-avoidance mechanisms. SLA variation of 20-60% could be ascribed to differences between functional groups and only 38-48% to different shrublands increasing from the predesert to the alpine. Alpine species display low PSI and N:P and high SLA, LNC, LPC, LCC, and C:N. On the contrary, predesert and semiarid showed high PSI and low SLA. SLA mediates the vegetative and reproductive phenological plant sequencing, high SLA is often associated with the overlapping in growth and reproductive phenophases with a seasonal reduction of vegetative growth, whereas low SLA is associated with vegetative and reproductive sequencing and a seasonal extension of vegetative growth. Species with drought-avoidance mechanisms (e.g., semideciduous species) contribute to an increase in the mean values of the SLA and LNC because these species show similar leaf and phenological patterns as the deciduous (high SLA and LNC and low PSI). The N:P indicates that only the alpine shrublands could present P limitations. The positive correlations between SLA and LPC and LNC and LPC (leaf economic spectrum) and the negative correlation between SLA and C:N were consistently maintained in the studied arid Mediterranean shrublands.
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110
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Ruiz T, Koussoroplis AM, Danger M, Aguer JP, Morel-Desrosiers N, Bec A. Quantifying the energetic cost of food quality constraints on resting metabolism to integrate nutritional and metabolic ecology. Ecol Lett 2021; 24:2339-2349. [PMID: 34337842 DOI: 10.1111/ele.13855] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/03/2021] [Accepted: 07/14/2021] [Indexed: 12/25/2022]
Abstract
Consumer metabolism controls the energy uptake from the environment and its allocation to biomass production. In natural ecosystems, available energy in food often fails to predict biomass production which is also (co)limited by the relative availability of various dietary compounds. To date, the link between energy metabolism and the effects of food chemical composition on biomass production remains elusive. Here, we measured the resting metabolic rate (RMR) of Daphnia magna along ontogeny when undergoing various (non-energetic) nutritional constraints. All types of dietary (co)limitations (Fatty acids, Sterols, Phosphorus) induced an increase in mass-specific RMR up to 128% between highest and lowest quality diets. We highlight a strong negative correlation between RMR and growth rate indicating RMR as a promising predictor of consumer growth rate. We argue that quantifying the energetic cost imposed by food quality on individual RMR may constitute a common currency enabling the integration of nutritional and metabolic ecology.
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Affiliation(s)
- Thomas Ruiz
- Université Clermont Auvergne, CNRS, LMGE, Clermont-Ferrand, France
| | | | | | | | | | - Alexandre Bec
- Université Clermont Auvergne, CNRS, LMGE, Clermont-Ferrand, France
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111
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Abstract
Autism is a common and complex neurologic disorder whose scientific underpinnings have begun to be established in the past decade. The essence of this breakthrough has been a focus on families, where genetic analyses are strongest, versus large-scale, case-control studies. Autism genetics has progressed in parallel with technology, from analyses of copy number variation to whole-exome sequencing (WES) and whole-genome sequencing (WGS). Gene mutations causing complete loss of function account for perhaps one-third of cases, largely detected through WES. This limitation has increased interest in understanding the regulatory variants of genes that contribute in more subtle ways to the disorder. Strategies combining biochemical analysis of gene regulation, WGS analysis of the noncoding genome, and machine learning have begun to succeed. The emerging picture is that careful control of the amounts of transcription, mRNA, and proteins made by key brain genes-stoichiometry-plays a critical role in defining the clinical features of autism.
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Affiliation(s)
- Robert B Darnell
- Laboratory of Molecular Neuro-Oncology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA;
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112
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Moon DL, Scott JT, Johnson TR. Stoichiometric imbalances complicate prediction of phytoplankton biomass in U.S. lakes: implications for nutrient criteria. Limnol Oceanogr 2021; 66:2967-2978. [PMID: 35919452 PMCID: PMC9337752 DOI: 10.1002/lno.11851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 05/02/2021] [Indexed: 06/15/2023]
Abstract
Using National Lakes Assessment data, we evaluated the influence of total N (TN), total P (TP), and other variables on lake chlorophyll-a concentrations. With simple linear regressions, high TN/TP samples biased predictions based on TN, and low TN/TP samples biased predictions based on TP. The bias problem was corrected, and correlation was improved, by splitting the dataset at the TN/TP ratio we estimated to be indicative of a balanced supply and developing separate regressions that predict chlorophyll-a based on TP, TN, dissolved inorganic N (DIN), dissolved organic carbon (DOC), non-algal light attenuation, depth, area, latitude, elevation, and conductivity. Both nutrients were excellent predictors, and non-algal light attenuation was the next most influential predictor. The regression analysis suggested that a potential for P only limitation (high TN/TP, 17% of samples) or N only limitation (low TN/TP, 14% of samples) can be inferred at the extremes of the TN/TP range. However, 69% of samples had an intermediate TN/TP ratio where it is difficult to infer anything about potential nutrient limitations (biomass could be N limited, P limited, N and P co-limited, or not limited by nutrients at all). Our results show that when developing phytoplankton response relationships using cross-lake datasets that span a wide range of trophic states, it is important to consider whether and how biomass is influenced by confounding factors - such as differences in the relative supply of N and P - so that biomass is not underestimated or overestimated, and nutrient criteria are not under-protective or over-protective.
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Affiliation(s)
- David L. Moon
- Water Quality Section, U.S. Environmental Protection Agency, Region 8, Denver, Colorado
| | - J. Thad Scott
- Department of Biology and Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas
| | - Tom R. Johnson
- Water Quality Section, U.S. Environmental Protection Agency, Region 8, Denver, Colorado
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Fernández-Martínez M, Corbera J, Cano-Rocabayera O, Sabater F, Preece C. Do Bryophyte Elemental Concentrations Explain Their Morphological Traits? Plants (Basel) 2021; 10:1581. [PMID: 34451627 PMCID: PMC8398013 DOI: 10.3390/plants10081581] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 11/17/2022]
Abstract
Differences in the elemental composition of plants, mainly C, N, and P, have been shown to be related to differences in their nutritional status, and their morphological and functional traits. The relationship between morphological traits and micronutrients and trace elements, however, has been much less studied. Additionally, in bryophytes, research devoted to investigating these relationships is still very scarce. Here, we analysed 80 samples from 29 aquatic and semi-aquatic (hygrophytic) moss species living in Mediterranean springs to investigate the relationship between moss nutrient concentrations and their micro- and macroscopic morphological traits and growth forms. We found that, across species, the elemental concentration of mosses was more tightly linked to macroscopic traits than to microscopic traits. Growth forms could also be successfully explained by the concentration of elements in mosses. Apart from macronutrients and their stoichiometric ratios (C:N, C:P, and N:P), micronutrients and trace elements were also important variables predicting moss morphological traits and growth forms. Additionally, our results showed that microscopic traits were well related to macroscopic traits. Overall, our results clearly indicate that the elemental composition of mosses can be used to infer their morphological traits, and that elements other than macronutrients should be taken into account to achieve a good representation of their morphological and, potentially, functional traits when comparing the elemental composition across species.
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Affiliation(s)
- Marcos Fernández-Martínez
- Research Group PLECO (Plants and Ecosystems), Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium;
- Delegació de la Serralada Litoral Central, ICHN, 08302 Mataró, Catalonia, Spain; (J.C.); (O.C.-R.); (F.S.)
| | - Jordi Corbera
- Delegació de la Serralada Litoral Central, ICHN, 08302 Mataró, Catalonia, Spain; (J.C.); (O.C.-R.); (F.S.)
| | - Oriol Cano-Rocabayera
- Delegació de la Serralada Litoral Central, ICHN, 08302 Mataró, Catalonia, Spain; (J.C.); (O.C.-R.); (F.S.)
- Department of Ecology, University of Barcelona, 08028 Barcelona, Catalonia, Spain
| | - Francesc Sabater
- Delegació de la Serralada Litoral Central, ICHN, 08302 Mataró, Catalonia, Spain; (J.C.); (O.C.-R.); (F.S.)
- Department of Ecology, University of Barcelona, 08028 Barcelona, Catalonia, Spain
| | - Catherine Preece
- Research Group PLECO (Plants and Ecosystems), Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium;
- Delegació de la Serralada Litoral Central, ICHN, 08302 Mataró, Catalonia, Spain; (J.C.); (O.C.-R.); (F.S.)
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114
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Zhang Q, Luo D, Yang L, Xie J, Yang Z, Zhou J, Li X, Xiong D, Chen Y, Yang Y. Variations in Rainfall Affect the Responses of Foliar Chemical Properties of Cunninghamia lanceolata Seedlings to Soil Warming. Front Plant Sci 2021; 12:705861. [PMID: 34394162 PMCID: PMC8363246 DOI: 10.3389/fpls.2021.705861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Climate warming is becoming an increasingly serious threat. Understanding plant stoichiometry changes under climate warming is crucial for predicting the effects of future warming on terrestrial ecosystem productivity. Nevertheless, how plant stoichiometry responds to warming when interannual rainfall variation is considered, remains poorly understood. We performed a field soil warming experiment (+5°C) using buried heating cables in subtropical areas of China from 2015 to 2018. Stoichiometric patterns of foliar C:N:P:K:Ca:Mg, non-structural carbohydrate, and stable isotope of Cunninghamia lanceolata seedlings were studied. Our results showed that soil warming decreased foliar P and K concentrations, C:Ca, P:Ca, and P:Mg ratios. However, soil warming increased foliar Ca concentration, δ15N value, C:P and N:P ratios. The response ratios of foliar N, C:N, and δ15N to soil warming were correlated with rainfall. Our findings indicate that there was non-homeostasis of N and C:N under warming conditions. Three possible reasons for this result are considered and include interannual variations in rainfall, increased loss of N, and N limitation in leaves. Piecewise structural equation models showed that stoichiometric non-homeostasis indirectly affected the growth of C. lanceolata seedlings in response to soil warming. Consequently, the growth of C. lanceolata seedlings remained unchanged under the warming treatment. Taken together, our results advance the understanding of how altered foliar stoichiometry relates to changes in plant growth in response to climate warming. Our results emphasize the importance of rainfall variations for modulating the responses of plant chemical properties to warming. This study provides a useful method for predicting the effects of climate warming on economically important timber species.
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Affiliation(s)
- Qiufang Zhang
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Dawei Luo
- Department of Renewable Resources, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada
| | - Liuming Yang
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Jinsheng Xie
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Zhijie Yang
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Jiacong Zhou
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Xiaojie Li
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Decheng Xiong
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Yuehmin Chen
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
| | - Yusheng Yang
- College of Geographical Science, Fujian Normal University, Fuzhou, China
- State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou, China
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115
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Choi MJ, Sagar LK, Sun B, Biondi M, Lee S, Najjariyan AM, Levina L, García de Arquer FP, Sargent EH. Ligand Exchange at a Covalent Surface Enables Balanced Stoichiometry in III-V Colloidal Quantum Dots. Nano Lett 2021; 21:6057-6063. [PMID: 34250796 DOI: 10.1021/acs.nanolett.1c01286] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
III-V colloidal quantum dots (CQDs) are promising semiconducting materials for optoelectronic applications; however, their strong covalent character requires a distinct approach to surface management compared with widely investigated II-VI and IV-VI CQDs-dots, which by contrast are characterized by an ionic nature. Here we show stoichiometric reconstruction in InAs CQDs by ligand exchange. In particular, we find that indium-carboxylate ligands, which passivate as-synthesized InAs CQDs and are responsible for In-rich surfaces, can be replaced by anionic ligands such as thiols. This enables the production of inks consisting of balanced-stoichiomety CQDs; this is distinct from what is observed in II-VI and IV-VI CQDs, in which thiols replace carboxylates. The approach enables the implementation of InAs CQD solids as the active layer in photodiode detectors that exhibit an external quantum efficiency of 36% at 930 nm and a photoresponse time of 65 ns, which is 4 times shorter than that of reference PbS CQD devices.
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Affiliation(s)
- Min-Jae Choi
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
- Department of Chemical and Biochemical Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Laxmi Kishore Sagar
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Bin Sun
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Margherita Biondi
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Seungjin Lee
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Amin Morteza Najjariyan
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Larissa Levina
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - F Pelayo García de Arquer
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Edward H Sargent
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
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116
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He H, Halpin JE, Popuri SR, Daly L, Bos JWG, Moody MP, MacLaren DA, Bagot PAJ. Atom Probe Tomography of a Cu-Doped TiNiSn Thermoelectric Material: Nanoscale Structure and Optimization of Analysis Conditions. Microsc Microanal 2021; 28:1-8. [PMID: 34315548 DOI: 10.1017/s1431927621012162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Cu-doping and crystallographic site occupations within the half-Heusler (HH) TiNiSn, a promising thermoelectric material, have been examined by atom probe tomography. In particular, this investigation aims to better understand the influence of atom probe analysis conditions on the measured chemical composition. Under a voltage-pulsing mode, atomic planes are clearly resolved and suggest an arrangement of elements in-line with the expected HH (F-43m space group) crystal structure. The Cu dopant is also distributed uniformly throughout the bulk material. For operation under laser-pulsed modes, the returned composition is highly dependent on the selected laser energy, with high energies resulting in the measurement of excessively high absolute Ti counts at the expense of Sn and in particular Ni. High laser energies also appear to be correlated with the detection of a high fraction of partial hits, indicating nonideal evaporation behavior. The possible mechanisms for these trends are discussed, along with suggestions for optimal analysis conditions for these and similar thermoelectric materials.
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Affiliation(s)
- Henry He
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
| | - John E Halpin
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Srinivas R Popuri
- Institute of Chemical Sciences and Centre for Advanced Energy Storage and Recovery, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Luke Daly
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
- Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, NSW 2006, Australia
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
- Space Science and Technology Centre, School of Earth and Planetary Science, Curtin University, Bentley, WA 6102, Australia
| | - Jan-Willem G Bos
- Institute of Chemical Sciences and Centre for Advanced Energy Storage and Recovery, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Michael P Moody
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
| | - Donald A MacLaren
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Paul A J Bagot
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
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117
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Gao P, Liu L, Li Y, Zhang LH, Wei JM, Zhao X, DU LX, Han W. Effects of anthracnose on C, N and P stoichiometry in the shoot of forage oat in north Shanxi Province, China. Ying Yong Sheng Tai Xue Bao 2021; 32:2477-2484. [PMID: 34313066 DOI: 10.13287/j.1001-9332.202107.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The C, N and P stoichiometry are helpful to understand the capacity of carbon assimilation and nutrient utilization efficiency during plant growth, as well as to diagnose nutrient limitation status. There is still a knowledge gap about the effects of disease on plant stoichiometry. In this study, forage oats (Avena sativa) suffering from anthracnose were the object of research conducted in north Shanxi Province. The C, N and P stoichiometry in the shoot of oat were examined at different degrees of disease occurrence. We analyzed the relationship of plant stoichiometry with disease duration, cultivar, and cultivation methods. The results showed that C, N and P contents decreased with the increasing degree of disease occurrence. The C, N and P contents in the plants with serious disease were significantly lower than that of healthy plants with a decreasing rate of 5.4%, 20.0% and 24.2%, respectively. C:N and C:P showed an increasing trend with the increases of the degree of disease occurrence. C:N and C:P of the plants with serious disease were significantly increased by 18.5% and 22.2%, respectively, than that of healthy plants. There was no significant difference for C content among different sampling sites, which indicated that the three varieties of forage oats might have disease tolerance capacity to ensure crop production. However, the stoichiometric values of N and P varied from place to place. The longer the disease duration was, the more reduction of N and P contents. Compared with monoculture oats, the P utilization efficiency of mixture oats was decreased by anthracnose. In summary, anthracnose had negative impacts on carbon assimilation capacity of forage oats in northern Shanxi. Anthracnose increased the restriction of N and P nutrition on the aboveground parts. However, anthracnose significantly improved N and P utilization efficiency. For the production practice, it was recommended to take necessary control measures to reduce the adverse effects of diseases on the economic benefits and ecological functions of forage oats.
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Affiliation(s)
- Peng Gao
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Lin Liu
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Yao Li
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Li-Hong Zhang
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Jiang-Ming Wei
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Xiang Zhao
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Li-Xia DU
- College of Grassland Science, Shanxi Agricultural University, Jinzhong 030801, Shanxi, China
| | - Wei Han
- Datong Qianye Pasture Science and Technology Limited Company, Tianzhen 038200, Shanxi, China
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118
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Lehmann J, Jørgensen ME, Fratz S, Müller HM, Kusch J, Scherzer S, Navarro-Retamal C, Mayer D, Böhm J, Konrad KR, Terpitz U, Dreyer I, Mueller TD, Sauer M, Hedrich R, Geiger D, Maierhofer T. Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis. Curr Biol 2021; 31:3575-3585.e9. [PMID: 34233161 DOI: 10.1016/j.cub.2021.06.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 02/03/2021] [Accepted: 06/08/2021] [Indexed: 10/20/2022]
Abstract
Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance.
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Affiliation(s)
- Julian Lehmann
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany; Department of Biotechnology and Biophysics, University of Würzburg, Biocenter -Am Hubland, Würzburg 97074, Germany
| | - Morten E Jørgensen
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Stefanie Fratz
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Heike M Müller
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Jana Kusch
- University Hospital Jena, Institute of Physiologie II, Kollegiengasse 9, Jena 07743, Germany
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Carlos Navarro-Retamal
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, 2 Norte 685, Talca, Chile
| | - Dominik Mayer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Jennifer Böhm
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Kai R Konrad
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Ulrich Terpitz
- Department of Biotechnology and Biophysics, University of Würzburg, Biocenter -Am Hubland, Würzburg 97074, Germany
| | - Ingo Dreyer
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, 2 Norte 685, Talca, Chile
| | - Thomas D Mueller
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, University of Würzburg, Biocenter -Am Hubland, Würzburg 97074, Germany
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany.
| | - Dietmar Geiger
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany
| | - Tobias Maierhofer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Institute, Würzburg 97082, Germany.
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119
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Williamson CJ, Turpin-Jelfs T, Nicholes MJ, Yallop ML, Anesio AM, Tranter M. Macro-Nutrient Stoichiometry of Glacier Algae From the Southwestern Margin of the Greenland Ice Sheet. Front Plant Sci 2021; 12:673614. [PMID: 34262580 PMCID: PMC8273243 DOI: 10.3389/fpls.2021.673614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/23/2021] [Indexed: 06/13/2023]
Abstract
Glacier algae residing within the surface ice of glaciers and ice sheets play globally significant roles in biogeochemical cycling, albedo feedbacks, and melt of the world's cryosphere. Here, we present an assessment of the macro-nutrient stoichiometry of glacier algal assemblages from the southwestern Greenland Ice Sheet (GrIS) margin, where widespread glacier algal blooms proliferate during summer melt seasons. Samples taken during the mid-2019 ablation season revealed overall lower cellular carbon (C), nitrogen (N), and phosphorus (P) content than predicted by standard microalgal cellular content:biovolume relationships, and elevated C:N and C:P ratios in all cases, with an overall estimated C:N:P of 1,997:73:1. We interpret lower cellular macro-nutrient content and elevated C:N and C:P ratios to reflect adaptation of glacier algal assemblages to their characteristic oligotrophic surface ice environment. Such lower macro-nutrient requirements would aid the proliferation of blooms across the nutrient poor cryosphere in a warming world. Up-scaling of our observations indicated the potential for glacier algal assemblages to accumulate ∼ 29 kg C km2 and ∼ 1.2 kg N km2 within our marginal surface ice location by the mid-ablation period (early August), confirming previous modeling estimates. While the long-term fate of glacier algal autochthonous production within surface ice remains unconstrained, data presented here provide insight into the possible quality of dissolved organic matter that may be released by assemblages into the surface ice environment.
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Affiliation(s)
- Christopher J. Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Thomas Turpin-Jelfs
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Miranda J. Nicholes
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Marian L. Yallop
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | | | - Martyn Tranter
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
- Department of Environmental Science, Aarhus University, Aarhus, Denmark
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120
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Xing K, Zhao M, Niinemets Ü, Niu S, Tian J, Jiang Y, Chen HYH, White PJ, Guo D, Ma Z. Relationships Between Leaf Carbon and Macronutrients Across Woody Species and Forest Ecosystems Highlight How Carbon Is Allocated to Leaf Structural Function. Front Plant Sci 2021; 12:674932. [PMID: 34177992 PMCID: PMC8226226 DOI: 10.3389/fpls.2021.674932] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/07/2021] [Indexed: 06/01/2023]
Abstract
Stoichiometry of leaf macronutrients can provide insight into the tradeoffs between leaf structural and metabolic investments. Structural carbon (C) in cell walls is contained in lignin and polysaccharides (cellulose, hemicellulose, and pectins). Much of leaf calcium (Ca) and a fraction of magnesium (Mg) were further bounded with cell wall pectins. The macronutrients phosphorus (P), potassium (K), and nitrogen (N) are primarily involved in cell metabolic functions. There is limited information on the functional interrelations among leaf C and macronutrients, and the functional dimensions characterizing the leaf structural and metabolic tradeoffs are not widely appreciated. We investigated the relationships between leaf C and macronutrient (N, P, K, Ca, Mg) concentrations in two widespread broad-leaved deciduous woody species Quercus wutaishanica (90 individuals) and Betula platyphylla (47 individuals), and further tested the generality of the observed relationships in 222 woody eudicots from 15 forest ecosystems. In a subsample of 20 broad-leaved species, we also analyzed the relationships among C, Ca, lignin, and pectin concentrations in leaf cell walls. We found a significant leaf C-Ca tradeoff operating within and across species and across ecosystems. This basic relationship was explained by variations in the share of cell wall lignin and pectin investments at the cell scale. The C-Ca tradeoffs were mainly driven by soil pH and mean annual temperature and precipitation, suggesting that leaves were more economically built with less C and more Ca as soil pH increased and at lower temperature and lower precipitation. However, we did not detect consistent patterns among C-N, and C-Mg at different levels of biological organization, suggesting substantial plasticity in N and Mg distribution among cell organelles and cell protoplast and cell wall. We observed two major axes of macronutrient differentiation: the cell-wall structural axis consisting of protein-free C and Ca and the protoplasm metabolic axis consisting of P and K, underscoring the decoupling of structural and metabolic elements inherently linked with cell wall from protoplasm investment strategies. We conclude that the tradeoffs between leaf C and Ca highlight how carbon is allocated to leaf structural function and suggest that this might indicate biogeochemical niche differentiation of species.
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Affiliation(s)
- Kaixiong Xing
- Key Laboratory of Ecosystem Network Observation and Modeling, Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Mingfei Zhao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Ülo Niinemets
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
- Estonian Academy of Sciences, Tallinn, Estonia
| | - Shuli Niu
- Key Laboratory of Ecosystem Network Observation and Modeling, Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Jing Tian
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, National Academy of Agriculture Green Development, Beijing, China
| | - Yuan Jiang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Han Y. H. Chen
- College of Natural Resources Management, Lakehead University, Thunder Bay, ON, Canada
- College of Geographical Sciences, Fujian Normal University, Fujian, China
| | - Philip J. White
- The James Hutton Institute, Dundee, United Kingdom
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Dali Guo
- Key Laboratory of Ecosystem Network Observation and Modeling, Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Zeqing Ma
- Key Laboratory of Ecosystem Network Observation and Modeling, Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
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Ellis-Soto D, Ferraro KM, Rizzuto M, Briggs E, Monk JD, Schmitz OJ. A methodological roadmap to quantify animal-vectored spatial ecosystem subsidies. J Anim Ecol 2021; 90:1605-1622. [PMID: 34014558 DOI: 10.1111/1365-2656.13538] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/04/2021] [Indexed: 12/31/2022]
Abstract
Energy, nutrients and organisms move over landscapes, connecting ecosystems across space and time. Meta-ecosystem theory investigates the emerging properties of local ecosystems coupled spatially by these movements of organisms and matter, by explicitly tracking exchanges of multiple substances across ecosystem borders. To date, meta-ecosystem research has focused mostly on abiotic flows-neglecting biotic nutrient flows. However, recent work has indicated animals act as spatial nutrient vectors when they transport nutrients across landscapes in the form of excreta, egesta and their own bodies. Partly due to its high level of abstraction, there are few empirical tests of meta-ecosystem theory. Furthermore, while animals may be viewed as important mediators of ecosystem functions, better integration of tools is needed to develop predictive insights of their relative roles and impacts on diverse ecosystems. We present a methodological roadmap that explains how to do such integration by discussing how to combine insights from movement, foraging and ecosystem ecology to develop a coherent understanding of animal-vectored nutrient transport on meta-ecosystems processes. We discuss how the slate of newly developed technologies and methods-tracking devices, mechanistic movement models, diet reconstruction techniques and remote sensing-that when integrated have the potential to advance the quantification of animal-vectored nutrient flows and increase the predictive power of meta-ecosystem theory. We demonstrate that by integrating novel and established tools of animal ecology, ecosystem ecology and remote sensing, we can begin to identify and quantify animal-mediated nutrient translocation by large animals. We also provide conceptual examples that show how our proposed integration of methodologies can help investigate ecosystem impacts of large animal movement. We conclude by describing practical advancements to understanding cross-ecosystem contributions of animals on the move. Understanding the mechanisms by which animals shape ecosystem dynamics is important for ongoing conservation, rewilding and restoration initiatives around the world, and for developing more accurate models of ecosystem nutrient budgets. Our roadmap will enable ecologists to better qualify and quantify animal-mediated nutrient translocation for animals on the move.
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Affiliation(s)
- Diego Ellis-Soto
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.,Center for Biodiversity and Global Change, Yale University, New Haven, CT, USA
| | | | - Matteo Rizzuto
- Department of Biology, Memorial University of Newfoundland, St. John's, Canada
| | - Emily Briggs
- School of the Environment, Yale University, New Haven, CT, USA.,Department of Anthropology, Yale University, New Haven, CT, USA
| | - Julia D Monk
- School of the Environment, Yale University, New Haven, CT, USA
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Lomozová Z, Catapano MC, Hrubša M, Karlíčková J, Macáková K, Kučera R, Mladěnka P. Chelation of Iron and Copper by Quercetin B-Ring Methyl Metabolites, Isorhamnetin and Tamarixetin, and Their Effect on Metal-Based Fenton Chemistry. J Agric Food Chem 2021; 69:5926-5937. [PMID: 34003649 DOI: 10.1021/acs.jafc.1c01729] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Quercetin, a common flavonoid from human diet, is extensively metabolized. Its two metabolites with the preserved flavonoid core were tested in detail for their interactions with transition metals, iron and copper. Both compounds chelated both metals; however, there were some significant differences between them notwithstanding that the major chelation site (3-hydroxy-4-keto) was the same. The complex stoichiometries were also determined under different pH conditions and in both oxidation states. Mostly, complexes 2:1, flavonoid to metal, were observed. Both compounds reduced iron and copper in a bell-shaped manner with tamarixetin being less potent in general. Both metabolites potentiated the Fenton reaction triggered by iron, while they were able to decrease the copper-based Fenton reaction under acidic conditions. In cellular experiments, both metabolites attenuated the copper-triggered hemolysis with isorhamnetin being more potent. In conclusion, there are differences between methylated metabolites of quercetin in relation to their interactions with biologically relevant transition metals.
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Affiliation(s)
- Zuzana Lomozová
- Department of Pharmacognosy, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Maria Carmen Catapano
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Marcel Hrubša
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Jana Karlíčková
- Department of Pharmaceutical Botany, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Kateřina Macáková
- Department of Pharmacognosy, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Radim Kučera
- Department of Pharmaceutical Chemistry and Pharmaceutical Analysis, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Přemysl Mladěnka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
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123
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Merino-Wong M, Niemeyer BA, Alansary D. Plasma Membrane Calcium ATPase Regulates Stoichiometry of CD4 + T-Cell Compartments. Front Immunol 2021; 12:687242. [PMID: 34093590 PMCID: PMC8175910 DOI: 10.3389/fimmu.2021.687242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
Immune responses involve mobilization of T cells within naïve and memory compartments. Tightly regulated Ca2+ levels are essential for balanced immune outcomes. How Ca2+ contributes to regulating compartment stoichiometry is unknown. Here, we show that plasma membrane Ca2+ ATPase 4 (PMCA4) is differentially expressed in human CD4+ T compartments yielding distinct store operated Ca2+ entry (SOCE) profiles. Modulation of PMCA4 yielded a more prominent increase of SOCE in memory than in naïve CD4+ T cell. Interestingly, downregulation of PMCA4 reduced the effector compartment fraction and led to accumulation of cells in the naïve compartment. In silico analysis and chromatin immunoprecipitation point towards Ying Yang 1 (YY1) as a transcription factor regulating PMCA4 expression. Analyses of PMCA and YY1 expression patterns following activation and of PMCA promoter activity following downregulation of YY1 highlight repressive role of YY1 on PMCA expression. Our findings show that PMCA4 adapts Ca2+ levels to cellular requirements during effector and quiescent phases and thereby represent a potential target to intervene with the outcome of the immune response.
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Affiliation(s)
| | | | - Dalia Alansary
- Molecular Biophysics, Saarland University, Homburg, Germany
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124
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Andersen CB, Yoshimura Y, Nielsen J, Otzen DE, Mulder FAA. How epigallocatechin gallate binds and assembles oligomeric forms of human alpha-synuclein. J Biol Chem 2021; 296:100788. [PMID: 34019875 PMCID: PMC8191297 DOI: 10.1016/j.jbc.2021.100788] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 11/25/2022] Open
Abstract
The intrinsically disordered human protein α-synuclein (αSN) can self-associate into oligomers and amyloid fibrils. Several lines of evidence suggest that oligomeric αSN is cytotoxic, making it important to devise strategies to either prevent oligomer formation and/or inhibit the ensuing toxicity. (−)-epigallocatechin gallate (EGCG) has emerged as a molecular modulator of αSN self-assembly, as it reduces the flexibility of the C-terminal region of αSN in the oligomer and inhibits the oligomer's ability to perturb phospholipid membranes and induce cell death. However, a detailed structural and kinetic characterization of this interaction is still lacking. Here, we use liquid-state NMR spectroscopy to investigate how EGCG interacts with monomeric and oligomeric forms of αSN. We find that EGCG can bind to all parts of monomeric αSN but exhibits highest affinity for the N-terminal region. Monomeric αSN binds ∼54 molecules of EGCG in total during oligomerization. Furthermore, kinetic data suggest that EGCG dimerization is coupled with the αSN association reaction. In contrast, preformed oligomers only bind ∼7 EGCG molecules per protomer, in agreement with the more compact nature of the oligomer compared with the natively unfolded monomer. In previously conducted cell assays, as little as 0.36 EGCG per αSN reduce oligomer toxicity by 50%. Our study thus demonstrates that αSN cytotoxicity can be inhibited by small molecules at concentrations at least an order of magnitude below full binding capacity. We speculate this is due to cooperative binding of protein-stabilized EGCG dimers, which in turn implies synergy between protein association and EGCG dimerization.
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Affiliation(s)
- Camilla B Andersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Yuichi Yoshimura
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark; Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - Janni Nielsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark.
| | - Frans A A Mulder
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark; Department of Chemistry, Aarhus University, Aarhus C, Denmark.
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125
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Leemsuthep A, Zakaria Z, Tanrattanakul V, Ramarad S, Muniyadi M, Jaruga T, Munusamy Y, Wnuk I, Pietrusiewicz P. Development of Porous Epoxy Micro-Beads Using Ammonium Bicarbonate through a Single Epoxy Droplet in Corn Oil. Materials (Basel) 2021; 14:ma14092282. [PMID: 33924997 PMCID: PMC8125122 DOI: 10.3390/ma14092282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 12/02/2022]
Abstract
This paper explored the effects of ammonium bicarbonate and different ratios of epoxy to polyamide on the formation of porous epoxy micro-beads through a single epoxy droplet. A single drop of a mixture, consisting of epoxy, polyamide, and ammonium bicarbonate, was dropped into heated corn oil at a temperature of 100 °C. An epoxy droplet was formed due to the immiscibility of the epoxy mixture and corn oil. The ammonium bicarbonate within this droplet underwent a decomposition reaction, while the epoxy and polyamide underwent a curing reaction, to form porous epoxy micro-beads. The result showed that the higher ammonium bicarbonate content in the porous, epoxy micro-beads increased the decomposition rate up to 11.52 × 10−3 cm3/s. In addition, a higher total volume of gas was generated when a higher ammonium bicarbonate content was decomposed. This led to the formation of porous epoxy micro-beads with a smaller particle size, lower specific gravity, and better thermal stability. At an epoxy to polyamide ratio of 10:6, many smaller micro-beads, with particle sizes ranging from 201 to 400 μm, were obtained at an ammonium bicarbonate content of 10 phr. Moreover, the porous epoxy micro-beads with open pores were shown to have a low specific gravity of about 0.93 and high thermal stability at a high ammonium bicarbonate content. Based on the findings, it was concluded that porous epoxy micro-beads were successfully produced using a single epoxy droplet in heated corn oil, where their shape and particle size depended on the content of ammonium bicarbonate and the ratio of epoxy to polyamide used.
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Affiliation(s)
- Anusha Leemsuthep
- Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis (UniMAP), Arau 02600, Malaysia;
- Geopolymer & Green Technology, Centre of Excellence (CEGeoGTech), Universiti Malaysia Perlis (UniMAP), Arau 02600, Malaysia
| | - Zunaida Zakaria
- Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis (UniMAP), Arau 02600, Malaysia;
- Geopolymer & Green Technology, Centre of Excellence (CEGeoGTech), Universiti Malaysia Perlis (UniMAP), Arau 02600, Malaysia
- Correspondence:
| | - Varaporn Tanrattanakul
- Research and Development Office, Sino-Thai International Rubber College, Prince of Songkla University, Songkhla 90110, Thailand;
| | - Suganti Ramarad
- School of Engineering and Physical Sciences, Heriot-Watt University Malaysia, Putrajaya 62200, Malaysia;
| | - Mathialagan Muniyadi
- Department of Petrochemical Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman (Perak Campus), Jalan Universiti, Bandar Barat, Kampar 31900, Malaysia; (M.M.); (Y.M.)
| | - Tomasz Jaruga
- Faculty of Mechanical Engineering and Computer Science, Częstochowa University of Technology, 42201 Częstochowa, Poland;
| | - Yamuna Munusamy
- Department of Petrochemical Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman (Perak Campus), Jalan Universiti, Bandar Barat, Kampar 31900, Malaysia; (M.M.); (Y.M.)
| | - Izabela Wnuk
- Department of Physics, Częstochowa University of Technology, 42201 Częstochowa, Poland; (I.W.); (P.P.)
| | - Paweł Pietrusiewicz
- Department of Physics, Częstochowa University of Technology, 42201 Częstochowa, Poland; (I.W.); (P.P.)
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126
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Siddique A, Ahmed R, Anderson J, Holtz M, Piner EL. Improved Electrical Properties of AlGaN/GaN High-Electron-Mobility Transistors by In Situ Tailoring the SiN x Passivation Layer. ACS Appl Mater Interfaces 2021; 13:18264-18273. [PMID: 33823581 DOI: 10.1021/acsami.1c01241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
In situ metal-organic chemical vapor deposition growth of SiNx passivation layers is reported on AlGaN/GaN high-electron-mobility transistors (HEMTs) without surface damage. A higher SiNx growth rate, when produced by higher SiH4 reactant gas flow, enables faster lateral coverage and coalescence of the initial SiNx islands, thereby suppressing SiH4-induced III-nitride etching. The effect of in situ SiNx passivation on the structural properties of AlGaN/GaN HEMTs has been evaluated using high-resolution X-ray diffraction. Electrical properties of the passivated HEMTs were evaluated by clover-leaf van der Pauw Hall measurements. The key findings include (a) a correlation of constituent gas chemistry with SiNx stoichiometry, (b) the degree of suppression of strain relaxation in the barrier layer that can be optimized through the SiNx stoichiometry, and (c) optimum strain relaxation by tailoring the SiNx passivation layer stoichiometry that can result in near-ideal AlGaN/AlN/GaN interfaces. The latter is expected to reduce the carrier scatterings and improve electron mobility. Under optimized conditions, low sheet resistance and high electron mobility are obtained. At 10 K, a sheet resistance of 33 Ω/sq and a mobility of 16,500 cm2/V-s are achieved. At 300 K, the sheet resistance is 336 Ω/sq and mobility is 2020 cm2/V-s with a sheet charge density of 0.78 × 1013 cm-2.
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Affiliation(s)
- Anwar Siddique
- Materials Science, Engineering and Commercialization Program, Texas State University, San Marcos, Texas 78666, United States
| | - Raju Ahmed
- Materials Science, Engineering and Commercialization Program, Texas State University, San Marcos, Texas 78666, United States
| | - Jonathan Anderson
- Materials Science, Engineering and Commercialization Program, Texas State University, San Marcos, Texas 78666, United States
| | - Mark Holtz
- Materials Science, Engineering and Commercialization Program, Texas State University, San Marcos, Texas 78666, United States
- Department of Physics, Texas State University, San Marcos, Texas 78666, United States
| | - Edwin L Piner
- Materials Science, Engineering and Commercialization Program, Texas State University, San Marcos, Texas 78666, United States
- Department of Physics, Texas State University, San Marcos, Texas 78666, United States
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127
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Qin P, Wu Z, Li P, Niu D, Liu M, Yin M. Triple-Modulated Chiral Inversion of Co-Assembly System Based on Alanine Amphiphile and Cyanostilbene Derivative. ACS Appl Mater Interfaces 2021; 13:18047-18055. [PMID: 33834761 DOI: 10.1021/acsami.1c03940] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The construction of chiroptical materials with controllable chirality is of special importance in biology and chemistry. Although tunable chirality can be realized in various systems, it remains a fundamental challenge to realize multimodulated chiral inversion. Herein, we report that chiral alanine derivative and fluorescent cyanostilbene derivative co-assemble to prepare supramolecular chiral systems, where twist nanofibers with totally inverted supramolecular chirality and circularly polarized luminescence are obtained through stoichiometric modulation. The supramolecular handedness can be inverted by means of altering the cooling rate and incorporating metal ions. The mechanism study reveals that the synergistic effect among hydrogen bonds, coordination interactions, and π-π stacking interactions contributes to the chirality inversion. This work establishes an effective strategy to precisely modulate supramolecular chirality in multiple ways, which shows great potential in developing smart chiroptical materials capable of achieving complex functionalities.
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Affiliation(s)
- Penghua Qin
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Zhen Wu
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Pengyu Li
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Dian Niu
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Minghua Liu
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Meizhen Yin
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, P. R. China
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128
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Abstract
The cyclic nature of specific conversions in the nitrogen cycle imposes strict limitations to the conversions observed in nature and explains for example why anaerobic ammonium oxidation (anammox) bacteria can only use nitrite – and not nitrate – as electron acceptor in catabolism, and why nitrite is required as additional electron donor for inorganic carbon fixation in anabolism. Furthermore, the biochemistry involved in nitrite-dependent anaerobic methane oxidation excludes the feasibility of using nitrate as electron acceptor. Based on the cyclic nature of these nitrogen conversions, we propose two scenarios that may explain the ecological role of recently discovered complete ammonia-oxidizing (comammox) Nitrospira spp., some of which were initially found in a strongly oxygen limited environment: (i) comammox Nitrospira spp. may actually catalyze an anammox-like metabolism using a biochemistry similar to intra-oxic nitrite-dependent methane oxidation, or (ii) scavenge all available oxygen for ammonia activation and use nitrate as terminal electron acceptor. Both scenarios require the presence of the biochemical machinery for ammonia oxidation to nitrate, potentially explaining a specific ecological niche for the occurrence of comammox bacteria in nature.
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Affiliation(s)
- Robbert Kleerebezem
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Sebastian Lücker
- Department of Microbiology, IWWR, Radboud University, Nijmegen, Netherlands
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129
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Tugaeva KV, Hawkins DEDP, Smith JLR, Bayfield OW, Ker DS, Sysoev AA, Klychnikov OI, Antson AA, Sluchanko NN. The Mechanism of SARS-CoV-2 Nucleocapsid Protein Recognition by the Human 14-3-3 Proteins. J Mol Biol 2021; 433:166875. [PMID: 33556408 PMCID: PMC7863765 DOI: 10.1016/j.jmb.2021.166875] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 12/24/2022]
Abstract
The coronavirus nucleocapsid protein (N) controls viral genome packaging and contains numerous phosphorylation sites located within unstructured regions. Binding of phosphorylated SARS-CoV N to the host 14-3-3 protein in the cytoplasm was reported to regulate nucleocytoplasmic N shuttling. All seven isoforms of the human 14-3-3 are abundantly present in tissues vulnerable to SARS-CoV-2, where N can constitute up to ~1% of expressed proteins during infection. Although the association between 14-3-3 and SARS-CoV-2 N proteins can represent one of the key host-pathogen interactions, its molecular mechanism and the specific critical phosphosites are unknown. Here, we show that phosphorylated SARS-CoV-2 N protein (pN) dimers, reconstituted via bacterial co-expression with protein kinase A, directly associate, in a phosphorylation-dependent manner, with the dimeric 14-3-3 protein, but not with its monomeric mutant. We demonstrate that pN is recognized by all seven human 14-3-3 isoforms with various efficiencies and deduce the apparent KD to selected isoforms, showing that these are in a low micromolar range. Serial truncations pinpointed a critical phosphorylation site to Ser197, which is conserved among related zoonotic coronaviruses and located within the functionally important, SR-rich region of N. The relatively tight 14-3-3/pN association could regulate nucleocytoplasmic shuttling and other functions of N via occlusion of the SR-rich region, and could also hijack cellular pathways by 14-3-3 sequestration. As such, the assembly may represent a valuable target for therapeutic intervention.
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Affiliation(s)
- Kristina V Tugaeva
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia
| | - Dorothy E D P Hawkins
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Jake L R Smith
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Oliver W Bayfield
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - De-Sheng Ker
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Andrey A Sysoev
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia
| | - Oleg I Klychnikov
- Department of Biochemistry, School of Biology, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Alfred A Antson
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom.
| | - Nikolai N Sluchanko
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia.
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130
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Wu MY, Chen L, Pang DB, Liu B, Liu LZ, Qiu KY, Li XB. [Changes of the concentrations and stoichiometry of carbon, nitrogen and phosphorus in soil aggregates along different altitudes of Helan Mountains, Northwest China.]. Ying Yong Sheng Tai Xue Bao 2021; 32:1241-1249. [PMID: 33899392 DOI: 10.13287/j.1001-9332.202104.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Exploring the distribution patterns of soil nutrients in aggregates of forests along different altitudes in arid and semi-arid areas can provide a theoretical basis for understanding nutrient cycling in vulnerable mountain ecosystems. In this study, we analyzed the distribution and stability of aggregates in the 0-20 cm soil layer along different altitudes (1380-2438 m) of Helan Mountains and measured the storage and stoichiometric characteristics of organic carbon, total nitrogen, and total phosphorus in soil aggregates. Results showed that the main soil aggregates of Helan Mountains changed from micro-aggregates (0.25-0.053 mm) to macro-aggregates (>0.25 mm) with increa-sing elevation. The mean weight diameter (MWD) and geometric mean diameter (GMD) of soil aggregates in high altitude (2139-2248 m) were significantly higher than those in low altitude (1380-1650 m). The content and storage of organic carbon and total nitrogen in soil aggregates of different size fractions were positively correlated with altitude, while the content of total phosphorus fluctuated with the increase in elevation and distributed uniformly in aggregates. Macro-aggregates and micro-aggregates had more contribution to soil nutrient storage than the silt and clay fractions, indicating that the proportion of aggregates with different size fractions was the key factor affecting soil nutrient storage and that macro-aggregates and micro-aggregates were the main carriers of soil nutrients. Moreover, the C:N ratio in aggregates of different size fractions did not change across different altitudes, whereas the C:P and N:P ratio were higher at mid and high elevations than those at low elevations. Our results indicated that the mid and high elevations of Helan Mountains had higher nutrient storage in the surface soil layer, and that higher content of macro-aggregates and micro-aggregates would help to retain organic carbon and nutrients in the soil. Soil nitrogen limitation was strong at low altitude in our study, suggesting that the appropriate amount of nitrogen addition in low altitudes could improve total nitrogen status during forest cultivation.
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Affiliation(s)
- Meng-Yao Wu
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Lin Chen
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Dan-Bo Pang
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Bo Liu
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Li-Zhen Liu
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Kai-Yang Qiu
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
| | - Xue-Bin Li
- Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Ningxia University, Yinchuan 750021, China
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China
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Liao VWY, Chebib M, Ahring PK. Efficient expression of concatenated α1β2δ and α1β3δ GABA A receptors, their pharmacology and stoichiometry. Br J Pharmacol 2021; 178:1556-1573. [PMID: 33491192 DOI: 10.1111/bph.15380] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 12/28/2020] [Accepted: 01/11/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE GABAA receptors containing δ-subunits are notorious for being difficult to study in vitro due to heterogeneity of expressed receptor populations and low GABA-evoked current amplitudes. Thus, there are some published misconceptions and contradictory conclusions made regarding the pharmacology and stoichiometry of δ-containing receptors. The aim of this study was to obtain robust homogenous expression of α1βδ receptors for in-depth investigation. EXPERIMENTAL APPROACH Novel δ-containing pentameric concatenated constructs were designed. The resulting α1β2δ and α1β3δ GABAA receptor concatemers were investigated by two-electrode voltage-clamp electrophysiology using Xenopus laevis oocytes. KEY RESULTS First, while homogenous α1βδ GABAA receptor pools could not be obtained by manipulating the ratio of injected cRNAs of free α1, β2/3, and δ subunits, concatenated pentameric α1β2δ and α1β3δ constructs resulted in robust expression levels of concatemers. Second, by using optimised constructs that give unidirectional assembly of concatemers, we found that the δ subunit cannot directly participate in GABA binding and receptor activation. Hence, functional δ-containing receptors are likely to all have a conventional 2α:2β:1δ stoichiometry arranged as βαβαδ when viewed counterclockwise from the extracellular side. Third, α1β2/3δ receptors were found to express efficiently in X. laevis oocytes but have a low estimated open probability of ~0.5% upon GABA activation. Because of this, these receptors are uniquely susceptible to positive allosteric modulation by, for example, neurosteroids. CONCLUSION AND IMPLICATIONS Our data answer important outstanding questions regarding the pharmacology and stoichiometry of α1δ-containing GABAA receptors and pave the way for future analysis and drug discovery efforts.
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Affiliation(s)
- Vivian Wan Yu Liao
- Brain and Mind Centre, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Mary Chebib
- Brain and Mind Centre, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Philip Kiaer Ahring
- Brain and Mind Centre, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
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Platzer M, Kiese S, Herfellner T, Schweiggert-Weisz U, Miesbauer O, Eisner P. Common Trends and Differences in Antioxidant Activity Analysis of Phenolic Substances Using Single Electron Transfer Based Assays. Molecules 2021; 26:molecules26051244. [PMID: 33669139 PMCID: PMC7956415 DOI: 10.3390/molecules26051244] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/19/2021] [Accepted: 02/23/2021] [Indexed: 12/18/2022] Open
Abstract
Numerous assays were developed to measure the antioxidant activity, but each has limitations and the results obtained by different methods are not always comparable. Popular examples are the DPPH and ABTS assay. Our aim was to study similarities and differences of these two assay regarding the measured antioxidant potentials of 24 phenolic compounds using the same measurement and evaluation methods. This should allow conclusions to be drawn as to whether one of the assays is more suitable for measuring specific subgroups like phenolic acids, flavonols, flavanones, dihydrochalcones or flavanols. The assays showed common trends for the mean values of most of the subgroups. Some dihydrochalcones and flavanones did not react with the DPPH radical in contrast to the ABTS radical, leading to significant differences. Therefore, to determine the antioxidant potential of dihydrochalcone or flavanone-rich extracts, the ABTS assay should be preferred. We found that the results of the flavonoids in the DPPH assay were dependent on the Bors criteria, whereas the structure–activity relationship in the ABTS assay was not clear. For the phenolic acids, the results in the ABTS assay were only high for pyrogallol structures, while the DPPH assay was mainly determined by the number of OH groups.
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Affiliation(s)
- Melanie Platzer
- ZIEL-Institute for Food & Health, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Weihenstephaner Berg 1, 85354 Freising, Germany;
- Fraunhofer Institue for Process Engineering and Packaging IVV, Giggenhauser Str. 35, 85354 Freising, Germany; (S.K.); (T.H.); (U.S.-W.)
- Correspondence:
| | - Sandra Kiese
- Fraunhofer Institue for Process Engineering and Packaging IVV, Giggenhauser Str. 35, 85354 Freising, Germany; (S.K.); (T.H.); (U.S.-W.)
- Chair of Food Packaging Technology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Weihenstephaner Steig 22, 85354 Freising, Germany;
| | - Thomas Herfellner
- Fraunhofer Institue for Process Engineering and Packaging IVV, Giggenhauser Str. 35, 85354 Freising, Germany; (S.K.); (T.H.); (U.S.-W.)
| | - Ute Schweiggert-Weisz
- Fraunhofer Institue for Process Engineering and Packaging IVV, Giggenhauser Str. 35, 85354 Freising, Germany; (S.K.); (T.H.); (U.S.-W.)
- Chair of Food Science, Institute for Nutritional and Food Sciences, University of Bonn, Meckenheimer Allee 166a, 53113 Bonn, Germany
| | - Oliver Miesbauer
- Chair of Food Packaging Technology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Weihenstephaner Steig 22, 85354 Freising, Germany;
| | - Peter Eisner
- ZIEL-Institute for Food & Health, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Weihenstephaner Berg 1, 85354 Freising, Germany;
- Fraunhofer Institue for Process Engineering and Packaging IVV, Giggenhauser Str. 35, 85354 Freising, Germany; (S.K.); (T.H.); (U.S.-W.)
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Abstract
Developmental plasticity is ubiquitous in natural populations, but the underlying causes and fitness consequences are poorly understood. For consumers, nutritional variation of juvenile diets is probably associated with plasticity in developmental rates, but little is known about how diet quality can affect phenotypic trajectories in ways that might influence survival to maturity and lifetime reproductive output. Here, we tested how the diet quality of a freshwater detritivorous isopod (Asellus aquaticus), in terms of elemental ratios of diet (i.e. carbon : nitrogen : phosphorus; C : N : P), can affect (i) developmental rates of body size and pigmentation and (ii) variation in juvenile survival. We reared 1047 individuals, in a full-sib split-family design (29 families), on either a high- (low C : P, C : N) or low-quality (high C : P, C : N) diet, and quantified developmental trajectories of body size and pigmentation for every individual over 12 weeks. Our diet contrast caused strong divergence in the developmental rates of pigmentation but not growth, culminating in a distribution of adult pigmentation spanning the broad range of phenotypes observed both within and among natural populations. Under low-quality diet, we found highest survival at intermediate growth and pigmentation rates. By contrast, survival under high-quality diet survival increased continuously with pigmentation rate, with longest lifespans at intermediate growth rates and high pigmentation rates. Building on previous work which suggests that visual predation mediates the evolution of cryptic pigmentation in A. aquaticus, our study shows how diet quality and composition can generate substantial phenotypic variation by affecting rates of growth and pigmentation during development in the absence of predation.
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Affiliation(s)
- Moritz D Lürig
- Department of Biology, Lund University, 22362 Lund, Sweden.,Department of Fish Ecology and Evolution, Eawag, Seestrasse 79, 6047 Kastanienbaum, Switzerland.,Department of Aquatic Ecology, Eawag, Seestrasse 79, 6047 Kastanienbaum, Switzerland
| | - Blake Matthews
- Department of Fish Ecology and Evolution, Eawag, Seestrasse 79, 6047 Kastanienbaum, Switzerland
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Jonnalagadda R, Del Rio Flores A, Cai W, Mehmood R, Narayanamoorthy M, Ren C, Zaragoza JPT, Kulik HJ, Zhang W, Drennan CL. Biochemical and crystallographic investigations into isonitrile formation by a nonheme iron-dependent oxidase/decarboxylase. J Biol Chem 2021; 296:100231. [PMID: 33361191 PMCID: PMC7949033 DOI: 10.1074/jbc.ra120.015932] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 12/21/2020] [Accepted: 12/27/2020] [Indexed: 11/23/2022] Open
Abstract
The isonitrile moiety is found in marine sponges and some microbes, where it plays a role in processes such as virulence and metal acquisition. Until recently only one route was known for isonitrile biosynthesis, a condensation reaction that brings together a nitrogen atom of l-Trp/l-Tyr with a carbon atom from ribulose-5-phosphate. With the discovery of ScoE, a mononuclear Fe(II) α-ketoglutarate-dependent dioxygenase from Streptomyces coeruleorubidus, a second route was identified. ScoE forms isonitrile from a glycine adduct, with both the nitrogen and carbon atoms coming from the same glycyl moiety. This reaction is part of the nonribosomal biosynthetic pathway of isonitrile lipopeptides. Here, we present structural, biochemical, and computational investigations of the mechanism of isonitrile formation by ScoE, an unprecedented reaction in the mononuclear Fe(II) α-ketoglutarate-dependent dioxygenase superfamily. The stoichiometry of this enzymatic reaction is measured, and multiple high-resolution (1.45-1.96 Å resolution) crystal structures of Fe(II)-bound ScoE are presented, providing insight into the binding of substrate, (R)-3-((carboxylmethyl)amino)butanoic acid (CABA), cosubstrate α-ketoglutarate, and an Fe(IV)=O mimic oxovanadium. Comparison to a previously published crystal structure of ScoE suggests that ScoE has an "inducible" α-ketoglutarate binding site, in which two residues arginine-157 and histidine-299 move by approximately 10 Å from the surface of the protein into the active site to create a transient α-ketoglutarate binding pocket. Together, data from structural analyses, site-directed mutagenesis, and computation provide insight into the mode of α-ketoglutarate binding, the mechanism of isonitrile formation, and how the structure of ScoE has been adapted to perform this unusual chemical reaction.
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Affiliation(s)
- Rohan Jonnalagadda
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Antonio Del Rio Flores
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California, USA
| | - Wenlong Cai
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California, USA
| | - Rimsha Mehmood
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | - Chaoxiang Ren
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California, USA
| | - Jan Paulo T Zaragoza
- Department of Chemistry, University of California Berkeley, Berkeley, California, USA; California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California, USA
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
| | - Wenjun Zhang
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California, USA; Chan Zuckerberg Biohub, San Francisco, California, USA.
| | - Catherine L Drennan
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
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135
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Zhou Y, Jiao L, Qin H, Li F. Effect of Environmental Stress on the Nutrient Stoichiometry of the Clonal Plant Phragmites australis in Inland Riparian Wetlands of Northwest China. Front Plant Sci 2021; 12:705319. [PMID: 34490007 PMCID: PMC8416684 DOI: 10.3389/fpls.2021.705319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/21/2021] [Indexed: 05/12/2023]
Abstract
Clonal plants play an important role in determining ecosystem properties such as community stability, species diversity and nutrient cycling. However, relatively little information is available about the stoichiometric characteristics of clonal plants and their drivers in inland riparian wetlands under strong environmental stress. In this manuscript, we studied the clonal plant Phragmites australis in an inland riparian wetland of Northwest China and compared its nutrient distribution and stoichiometry trade-offs as well as its responses to soil environmental factors in three different environments, namely, a wetland, a salt marsh, and a desert. We found that (1) P. australis could adapt to heterogeneous environments by changing its nutrient allocation strategies, as evidenced by the significant decrease in N and P concentrations, and significant increase in whole-plant C:P and N:P ratios from the wetland to the desert habitats. (2) P. australis adapted to stressful environments by changing its nutrient allocation patterns among different modules, showing a greater tendency to invest N and P in underground modules (rhizomes and roots) and an increase in the utilization efficiency of N and P in the leaves, and stems as environmental stress increased. (3) The C-N, C-P, and N:P-C in the whole plant and in each module showed significant anisotropic growth relationships in the three habitats (P < 0.05). (4) Soil water, pH and salt were the main factors limiting nutrient stoichiometry. The results of this study clarified the ecological adaptation mechanism of the clonal plant P. australis to heterogeneous environments and provided targeted protection strategies for inland riparian wetlands in Northwest China.
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Affiliation(s)
- Yi Zhou
- College of Geography and Environment Science, Northwest Normal University, Lanzhou, China
- Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu, China
| | - Liang Jiao
- College of Geography and Environment Science, Northwest Normal University, Lanzhou, China
- Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu, China
- *Correspondence: Liang Jiao,
| | - Huijun Qin
- College of Geography and Environment Science, Northwest Normal University, Lanzhou, China
- Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu, China
| | - Fang Li
- College of Geography and Environment Science, Northwest Normal University, Lanzhou, China
- Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu, China
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Allesson L, Andersen T, Dörsch P, Eiler A, Wei J, Hessen DO. Corrigendum: Phosphorus Availability Promotes Bacterial DOC-Mineralization, but Not Cumulative CO 2-Production. Front Microbiol 2020; 11:614974. [PMID: 33329505 PMCID: PMC7720007 DOI: 10.3389/fmicb.2020.614974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 10/27/2020] [Indexed: 11/18/2022] Open
Affiliation(s)
- Lina Allesson
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Tom Andersen
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Peter Dörsch
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - Alexander Eiler
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Jing Wei
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Dag O Hessen
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
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137
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Schönekerl S, Acker J. The Kinetics and Stoichiometry of Metal Cation Reduction on Multi-Crystalline Silicon in a Dilute Hydrofluoric Acid Matrix. Nanomaterials (Basel) 2020; 10:E2545. [PMID: 33348864 PMCID: PMC7766330 DOI: 10.3390/nano10122545] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/11/2020] [Accepted: 12/13/2020] [Indexed: 11/16/2022]
Abstract
In this study, the process of metal cation reduction on multi-crystalline silicon in a dilute hydrofluoric acid (HF) matrix is described using Ag(I), Cu(II), Au(III) and Pt(IV). The experimental basis utilized batch tests with various solutions of different metal cation and HF concentrations and multi-crystalline silicon wafers. The metal deposition kinetics and the stoichiometry of metal deposition and silicon dissolution were calculated by means of consecutive sampling and analysis of the solutions. Several reaction mechanisms and reaction steps of the process were discussed by overlaying the results with theoretical considerations. It was deduced that the metal deposition was fastest if the holes formed during metal ion reduction could be transferred to the valence bands of the bulk and surface silicon with hydrogen termination. By contrast, the kinetics were lowest when the redox levels of the metal ion/metal half-cells were weak and the equilibrium potential of the H3O+/H2 half-cells was high. Further minima were identified at the thresholds where H3O+ reduction was inhibited, the valence transfer via valence band mechanism was limited by a Schottky barrier and the dissolution of oxidized silicon was restricted by the activity of the HF species F-, HF2- and H2F3-. The findings of the stoichiometric conditions provided further indications of the involvement of H3O+ and H2O as oxidizing agents in addition to metal ions, and the hydrogen of the surface silicon termination as a reducing agent in addition to the silicon. The H3O+ reduction is the predominant process in dilute metal ion solutions unless it is disabled due to the metal-dependent equilibrium potential of the H3O+/H2 half-cell and the energetic level of the valence bands of the silicon. As silicon is not oxidized up to the oxidation state +IV by the reduction of the metal ions and H3O+, water is suspected of acting as a secondary oxidant. The stoichiometric ratios increased up to a maximum with higher molalities of the metal ions, in the manner of a sigmoidal function. If, owing to the redox level of the metal half-cells and the energetic level of the valence band at the metal-silicon contact, the surface silicon can be oxidized, the hydrogen of the termination is the further reducing agent.
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Affiliation(s)
- Stefan Schönekerl
- Department of Physical Chemistry, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Universitätsplatz 1, 01968 Senftenberg, Germany;
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138
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Xu MP, Zhang XY, Li WJ, Ren CJ, Yang GH, Han XH. [Leaf nutrient resorption characteristics of Robinia pseudoacacia at different ages and their response to soil nutrient availability]. Ying Yong Sheng Tai Xue Bao 2020; 31:3357-3364. [PMID: 33314825 DOI: 10.13287/j.1001-9332.202010.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
To reveal nutrient resorption characteristics of Robinia pseudoacacia and their driving factors in hilly and gully regions, we measured the concentration of total nitrogen and total phosphorus in leaves and the concentrations and stoichiometry of organic carbon, total nitrogen, total phospho-rus, ammonium, nitrate and available phosphorus in soils of R. pseudoacacia plantations with different stand ages. We analyzed the relationship between leaf nitrogen and phosphorus resorption efficiencies and soil nutrient characteristics. The nutrients in plants and soil changed significantly with stand ages. The total and available phosphorus concentrations were low in the soil. Nitrogen resorption efficiency first increased and then decreased with the increases of stand age, with a range of 48.2%-54.0% and a mean value of 48.5%. Phosphorus resorption efficiency increased significantly with stand age, with a range of 45.2%-49.4% and a mean value of 46.9%. Nitrogen resorption efficiency showed negative response to soil nitrogen and N:P. Phosphorus resorption efficiency was significantly positively correlated to soil N:P and negatively correlated to soil available phosphorus. Our results indicated that soil nutrient availability negatively drove nutrient resorption efficiency. The strategies of leaf nutrient resorption responded strongly to soil N:P due to the N2-fixing effect and P-limitation of R. pseudoacacia.
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Affiliation(s)
- Miao-Ping Xu
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
| | - Xin-Yi Zhang
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
| | - Wen-Jie Li
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
| | - Cheng-Jie Ren
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
| | - Gai-He Yang
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
| | - Xin-Hui Han
- College of Agronomy, Northwest A&F University/Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, Shaanxi, China
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139
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Naulin PA, Lozano B, Fuentes C, Liu Y, Schmidt C, Contreras JE, Barrera NP. Polydisperse molecular architecture of connexin 26/30 heteromeric hemichannels revealed by atomic force microscopy imaging. J Biol Chem 2020; 295:16499-16509. [PMID: 32887797 PMCID: PMC7864052 DOI: 10.1074/jbc.ra119.012128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 08/31/2020] [Indexed: 11/06/2022] Open
Abstract
Connexin (Cx) protein forms hemichannels and gap junctional channels, which play diverse and profound roles in human physiology and diseases. Gap junctions are arrays of intercellular channels formed by the docking of two hemichannels from adjacent cells. Each hexameric hemichannel contains the same or different Cx isoform. Although homomeric Cxs forms have been largely described functionally and structurally, the stoichiometry and arrangement of heteromeric Cx channels remain unknown. The latter, however, are widely expressed in human tissues and variation might have important implications on channel function. Investigating properties of heteromeric Cx channels is challenging considering the high number of potential subunit arrangements and stoichiometries, even when only combining two Cx isoforms. To tackle this problem, we engineered an HA tag onto Cx26 or Cx30 subunits and imaged hemichannels that were liganded by Fab-epitope antibody fragments via atomic force microscopy. For Cx26-HA/Cx30 or Cx30-HA/Cx26 heteromeric channels, the Fab-HA binding distribution was binomial with a maximum of three Fab-HA bound. Furthermore, imaged Cx26/Cx30-HA triple liganded by Fab-HA showed multiple arrangements that can be derived from the law of total probabilities. Atomic force microscopy imaging of ringlike structures of Cx26/Cx30-HA hemichannels confirmed these findings and also detected a polydisperse distribution of stoichiometries. Our results indicate a dominant subunit stoichiometry of 3Cx26:3Cx30 with the most abundant subunit arrangement of Cx26-Cx26-Cx30-Cx26-Cx30-Cx30. To our knowledge, this is the first time that the molecular architecture of heteromeric Cx channels has been revealed, thus providing the basis to explore the functional effect of these channels in biology.
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Affiliation(s)
- Pamela A Naulin
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Benjamin Lozano
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Christian Fuentes
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Yu Liu
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey, USA
| | - Carla Schmidt
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Jorge E Contreras
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey, USA
| | - Nelson P Barrera
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
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140
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Yu Y, Liu H, Yu Z, Witkowska HE, Cheng Y. Stoichiometry of Nucleotide Binding to Proteasome AAA+ ATPase Hexamer Established by Native Mass Spectrometry. Mol Cell Proteomics 2020; 19:1997-2015. [PMID: 32883800 PMCID: PMC7710143 DOI: 10.1074/mcp.ra120.002067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/04/2020] [Indexed: 11/06/2022] Open
Abstract
AAA+ ATPases constitute a large family of proteins that are involved in a plethora of cellular processes including DNA disassembly, protein degradation and protein complex disassembly. They typically form a hexametric ring-shaped structure with six subunits in a (pseudo) 6-fold symmetry. In a subset of AAA+ ATPases that facilitate protein unfolding and degradation, six subunits cooperate to translocate protein substrates through a central pore in the ring. The number and type of nucleotides in an AAA+ ATPase hexamer is inherently linked to the mechanism that underlies cooperation among subunits and couples ATP hydrolysis with substrate translocation. We conducted a native MS study of a monodispersed form of PAN, an archaeal proteasome AAA+ ATPase, to determine the number of nucleotides bound to each hexamer of the WT protein. We utilized ADP and its analogs (TNP-ADP and mant-ADP), and a nonhydrolyzable ATP analog (AMP-PNP) to study nucleotide site occupancy within the PAN hexamer in ADP- and ATP-binding states, respectively. Throughout all experiments we used a Walker A mutant (PANK217A) that is impaired in nucleotide binding as an internal standard to mitigate the effects of residual solvation on mass measurement accuracy and to serve as a reference protein to control for nonspecific nucleotide binding. This approach led to the unambiguous finding that a WT PAN hexamer carried - from expression host - six tightly bound ADP molecules that could be exchanged for ADP and ATP analogs. Although the Walker A mutant did not bind ADP analogs, it did bind AMP-PNP, albeit at multiple stoichiometries. We observed variable levels of hexamer dissociation and an appearance of multimeric species with the over-charged molecular ion distributions across repeated experiments. We posit that these phenomena originated during ESI process at the final stages of ESI droplet evolution.
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Affiliation(s)
- Yadong Yu
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - Haichuan Liu
- Department of OBGYN & Reproductive Sci, Sandler-Moore MS Core Facility, University of California San Francisco, San Francisco, California, USA
| | - Zanlin Yu
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - H Ewa Witkowska
- Department of OBGYN & Reproductive Sci, Sandler-Moore MS Core Facility, University of California San Francisco, San Francisco, California, USA.
| | - Yifan Cheng
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA; Howard Hughes Medical Institute, University of California San Francisco, San Francisco, California, USA.
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141
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Iannino A, Vosshage ATL, Weitere M, Fink P. Taxonomic Shift Over a Phosphorus Gradient Affects the Stoichiometry and Fatty Acid Composition of Stream Periphyton. J Phycol 2020; 56:1687-1695. [PMID: 32738149 DOI: 10.1111/jpy.13060] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 07/12/2020] [Indexed: 06/11/2023]
Abstract
Phosphorus enrichment of stream ecosystems generally increases primary production in the benthos, but the consequences of eutrophication for the nutritional quality of periphyton for grazers are less clear. On short timescales, high phosphorus inputs may lead to reduced C:P ratios and high essential fatty acid contents of periphyton, which are both considered important determinants of food quality for grazers. However, nutrient enrichment may alter the taxonomic composition of periphyton and favor the growth of less palatable algal taxa. In this study, periphyton was grown under a gradient of dissolved phosphorus availability from 5 to 100 µg P · L-1 , to investigate eutrophication effects on periphyton taxonomy, C:N:P stoichiometry, and fatty acid composition. After 1 month, periphyton grown under oligotrophic conditions was mainly composed of diatoms (~86%). With increasing phosphorus availability, diatoms were gradually outcompeted by chlorophytes and cyanobacteria, which were the predominant taxon under eutrophic conditions. Unexpectedly, periphyton C:P ratios increased with greater phosphorus supply, from ~280 under oligotrophic conditions up to ~790 at 100 µg · L-1 , reflecting a tendency of chlorophytes and cyanobacteria to produce more biomass per unit of assimilated phosphorus compared to diatoms. Periphyton content of essential polyunsaturated fatty acids relative to biomass followed a unimodal relationship with phosphorus availability and peaked at intermediate phosphorus levels, likely as a result of both taxonomic and nutrient effects. Our results demonstrate that phosphorus-driven eutrophication of freshwater ecosystems may worsen periphyton nutritional quality due to taxonomic sorting, which may further lead to lower growth and reproduction of herbivores.
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Affiliation(s)
- Alessandra Iannino
- Workgroup Aquatic Chemical Ecology, University of Cologne Biocentre, Zülpichestrasse 47B, 50674, Cologne, Germany
| | - Alexander Tim Ludwig Vosshage
- Department of River Ecology, Helmholtz Centre for Environmental Research (UFZ), Brückstrasse 3A, 39114, Magdeburg, Germany
| | - Markus Weitere
- Department of River Ecology, Helmholtz Centre for Environmental Research (UFZ), Brückstrasse 3A, 39114, Magdeburg, Germany
| | - Patrick Fink
- Workgroup Aquatic Chemical Ecology, University of Cologne Biocentre, Zülpichestrasse 47B, 50674, Cologne, Germany
- Department of River Ecology & Department of Aquatic Ecosystem Analysis and Management, Helmholtz Centre for Environmental Research (UFZ), Brückstrasse 3A, 39114, Magdeburg, Germany
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142
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Kumar N, Haviar S, Rezek J, Baroch P, Zeman P. Tuning Stoichiometry and Structure of Pd-WO 3-x Thin Films for Hydrogen Gas Sensing by High-Power Impulse Magnetron Sputtering. Materials (Basel) 2020; 13:E5101. [PMID: 33198193 PMCID: PMC7697909 DOI: 10.3390/ma13225101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 11/02/2020] [Accepted: 11/06/2020] [Indexed: 06/11/2023]
Abstract
By tuning the deposition parameters of reactive high-power impulse magnetron sputtering, specifically the pulse length, we were able to prepare WO3-x films with various stoichiometry and structure. Subsequently, the films were annealed in air at moderate temperature (350 °C). We demonstrate that the stoichiometry of the as-deposited films influences considerably the type of crystalline phase formed in the annealed films. The appropriate sub-stoichiometry of the films (approx. WO2.76) enabled crystallization of the monoclinic phase during the annealing. This phase is favorable for hydrogen sensing applications. To characterize the sensory behavior of the films, the tungsten oxide films were decorated by Pd nanoparticles before annealing and were assembled as a conductometric gas sensor. The sensory response of the films that crystallized in the monoclinic structure was proven to be superior to that of the films containing other phases.
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Affiliation(s)
| | - Stanislav Haviar
- Department of Physics and NTIS—European Centre of Excellence, Faculty of Applied Sciences, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (N.K.); (J.R.); (P.B.); (P.Z.)
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143
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Allesson L, Andersen T, Dörsch P, Eiler A, Wei J, Hessen DO. Phosphorus Availability Promotes Bacterial DOC-Mineralization, but Not Cumulative CO 2-Production. Front Microbiol 2020; 11:569879. [PMID: 33072029 PMCID: PMC7541949 DOI: 10.3389/fmicb.2020.569879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/25/2020] [Indexed: 11/13/2022] Open
Abstract
The current trend of increasing input of terrestrially derived dissolved organic carbon (DOC) to boreal freshwater systems is causing increased levels of carbon dioxide (CO2) supersaturation and degassing. Phosphorus (P) is often the most limiting nutrient for bacterial growth and would thus be expected to increase overall mineralization rates and CO2 production. However, high carbon (C) to P ratios of terrestrially derived DOC could also cause elevated cell-specific respiration of the excess C in heterotrophic bacteria. Using data from a survey of 75 Scandinavian lakes along an ecosystem gradient of DOC, we estimated in situ CO2 production rates. These rates showed a unimodal response with DOC-specific CO2 production negatively related to DOC:total phosphorus (TP) ratio, and a turning point at 5 mg C L-1, indicating higher DOC turnover rates in productive than in unproductive lakes. To further assess the dependency of bacterial respiration (BR) on DOC and P, we monitored CO2 production in incubations of water with a gradient of DOC crossed with two levels of inorganic P. Finally, we crossed DOC and P with a temperature gradient to test the temperature dependency of respiration rates [as oxygen (O2) consumption]. While total CO2 production seemed to be unaffected by P additions, respiration rates, and growth yields, as estimated by ribosomal gene copy numbers, suggest increased bacterial growth and decreased cell-specific respiration under non-limited P conditions. Respiration rates showed a sigmoid response to increasing DOC availability reaching a plateau at about 20 mg C L-1 of initial DOC concentrations. In addition to these P and DOC level effects, respiration rates responded in a non-monotonic fashion to temperature with an increase in respiration rates by a factor of 2.6 (±0.2) from 15 to 25°C and a decrease above 30°C. The combined results from the survey and experiments highlight DOC as the major determinant of CO2 production in boreal lakes, with P and temperature as significant modulators of respiration kinetics.
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Affiliation(s)
- Lina Allesson
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Tom Andersen
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Peter Dörsch
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - Alexander Eiler
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Jing Wei
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Dag O Hessen
- Department of Biosciences and Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
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144
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Metson GS, MacDonald GK, Leach AM, Compton JE, Harrison JA, Galloway JN. The U.S. consumer phosphorus footprint: where do nitrogen and phosphorus diverge? Environ Res Lett 2020; 15:1-15. [PMID: 35990174 PMCID: PMC9389546 DOI: 10.1088/1748-9326/aba781] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Phosphorus (P) and nitrogen (N) are essential nutrients for food production but their excess use in agriculture can have major social costs, particularly related to water quality degradation. Nutrient footprint approaches estimate N and P release to the environment through food production and waste management and enable linking these emissions to particular consumption patterns. Following an established method for quantifying a consumer-oriented N footprint for the United States (U.S.), we calculate an analogous P footprint and assess the N:P ratio across different stages of food production and consumption. Circa 2012, the average consumer's P footprint was 4.4 kg P capita-1 yr-1 compared to 22.4 kg N capita-1 yr-1 for the food portion of the N footprint. Animal products have the largest contribution to both footprints, comprising >70% of the average per capita N and P footprints. The N:P ratio of environmental release based on virtual nutrient factors (kilograms N or P per kilogram of food consumed) varies considerably across food groups and stages. The overall N:P ratio of the footprints was lower (5.2 by mass) than for that of U.S. food consumption (8.6), reinforcing our finding that P is managed less efficiently than N in food production systems but more efficiently removed from wastewater. While strategies like reducing meat consumption will effectively reduce both N and P footprints by decreasing overall synthetic fertilizer nutrient demands, consideration of how food production and waste treatment differentially affect N and P releases to the environment can also inform eutrophication management.
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Affiliation(s)
- Geneviève S Metson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
- National Research Council, National Academies of Science, Washington, DC, United States of America
- Pacific Ecological Systems Division, US Environmental Protection Agency, Corvallis, OR, United States of America
- School of the Environment, Washington State University, Vancouver, WA, United States of America
| | | | - Allison M Leach
- The Sustainability Institute, University of New Hampshire, Durham, NH, United States of America
| | - Jana E Compton
- Pacific Ecological Systems Division, US Environmental Protection Agency, Corvallis, OR, United States of America
| | - John A Harrison
- School of the Environment, Washington State University, Vancouver, WA, United States of America
| | - James N Galloway
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA, United States of America
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145
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Penuelas J, Krisztin T, Obersteiner M, Huber F, Winner H, Janssens IA, Ciais P, Sardans J. Country-Level Relationships of the Human Intake of N and P, Animal and Vegetable Food, and Alcoholic Beverages with Cancer and Life Expectancy. Int J Environ Res Public Health 2020; 17:E7240. [PMID: 33022999 PMCID: PMC7579602 DOI: 10.3390/ijerph17197240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 09/27/2020] [Accepted: 09/28/2020] [Indexed: 01/26/2023]
Abstract
BACKGROUND The quantity, quality, and type (e.g., animal and vegetable) of human food have been correlated with human health, although with some contradictory or neutral results. We aimed to shed light on this association by using the integrated data at country level. METHODS We correlated elemental (nitrogen (N) and phosphorus (P)) compositions and stoichiometries (N:P ratios), molecular (proteins) and energetic traits (kilocalories) of food of animal (terrestrial or aquatic) and vegetable origin, and alcoholic beverages with cancer prevalence and mortality and life expectancy (LE) at birth at the country level. We used the official databases of United Nations (UN), Food and Agriculture Organization of the United Nations (FAO), Organization for Economic Co-operation and Development (OECD), World Bank, World Health Organization (WHO), U.S. Department of Agriculture, U.S. Department of Health, and Eurobarometer, while also considering other possibly involved variables such as income, mean age, or human development index of each country. RESULTS The per capita intakes of N, P, protein, and total intake from terrestrial animals, and especially alcohol were significantly and positively associated with prevalence and mortality from total, colon, lung, breast, and prostate cancers. In contrast, high per capita intakes of vegetable N, P, N:P, protein, and total plant intake exhibited negative relationships with cancer prevalence and mortality. However, a high LE at birth, especially in underdeveloped countries was more strongly correlated with a higher intake of food, independent of its animal or vegetable origin, than with other variables, such as higher income or the human development index. CONCLUSIONS Our analyses, thus, yielded four generally consistent conclusions. First, the excessive intake of terrestrial animal food, especially the levels of protein, N, and P, is associated with higher prevalence of cancer, whereas equivalent intake from vegetables is associated with lower prevalence. Second, no consistent relationship was found for food N:P ratio and cancer prevalence. Third, the consumption of alcoholic beverages correlates with prevalence and mortality by malignant neoplasms. Fourth, in underdeveloped countries, reducing famine has a greater positive impact on health and LE than a healthier diet.
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Affiliation(s)
- Josep Penuelas
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, 08193 Cerdanyola del Vallès, Spain;
- CREAF, 08193 Cerdanyola del Vallès, Spain
| | - Tamás Krisztin
- International Institute for Applied Systems Analysis (IIASA), Ecosystems Services and Management, Schlossplatz 1, A-2361 Laxenburg, Austria; (T.K.); (M.O.)
| | - Michael Obersteiner
- International Institute for Applied Systems Analysis (IIASA), Ecosystems Services and Management, Schlossplatz 1, A-2361 Laxenburg, Austria; (T.K.); (M.O.)
| | - Florian Huber
- Paris Lodron University of Salzburg, Mönchsberg 2a, A-5020 Salzburg, Austria; (F.H.); (H.W.)
| | - Hannes Winner
- Paris Lodron University of Salzburg, Mönchsberg 2a, A-5020 Salzburg, Austria; (F.H.); (H.W.)
- Austrian Institute of Economic Research (WIFO), Arsenal Objekt 20, A-1030 Vienna, Austria
| | - Ivan A. Janssens
- Research Group Plants and Ecosystems (PLECO), Department of Biology, University of Antwerp, B-2610 Wilrijk, Belgium;
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l’Environnement, IPSL, 91191 Gif-sur-Yvette, France;
| | - Jordi Sardans
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, 08193 Cerdanyola del Vallès, Spain;
- CREAF, 08193 Cerdanyola del Vallès, Spain
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146
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Olson CR, Solomon CT, Jones SE. Shifting limitation of primary production: experimental support for a new model in lake ecosystems. Ecol Lett 2020; 23:1800-1808. [PMID: 32945617 PMCID: PMC7756323 DOI: 10.1111/ele.13606] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/20/2020] [Accepted: 08/13/2020] [Indexed: 01/07/2023]
Abstract
The limits on primary production vary in complex ways across space and time. Strong tests of clear conceptual models have been instrumental in understanding these patterns in both terrestrial and aquatic ecosystems. Here we present the first experimental test of a new model describing how shifts from nutrient to light limitation control primary productivity in lake ecosystems as hydrological inputs of nutrients and organic matter vary. We found support for two key predictions of the model: that gross primary production (GPP) follows a hump-shaped relationship with increasing dissolved organic carbon (DOC) concentrations; and that the maximum GPP, and the critical DOC concentration at which the hump occurs, are determined by the stoichiometry and chromophoricity of the hydrological inputs. Our results advance fundamental understanding of the limits on aquatic primary production, and have important applications given ongoing anthropogenic alterations of the nutrient and organic matter inputs to surface waters.
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Affiliation(s)
- Carly R Olson
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
| | | | - Stuart E Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
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147
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An Z, Liu P, Zheng J, Si C, Li T, Chen Y, Ma T, Zhang MQ, Zhou Q, Ding S. Sox2 and Klf4 as the Functional Core in Pluripotency Induction without Exogenous Oct4. Cell Rep 2019; 29:1986-2000.e8. [PMID: 31722212 DOI: 10.1016/j.celrep.2019.10.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 06/11/2019] [Accepted: 10/07/2019] [Indexed: 12/11/2022] Open
Abstract
Ectopic expression of Oct4, Sox2, Klf4, and c-Myc can reprogram differentiated somatic cells into induced pluripotent stem cells (iPSCs). For years, Oct4 has been considered the key reprogramming factor core of the four factors. Here, we challenge this view by reporting a core function of Sox2 and Klf4 in reprogramming. We found that polycistronic expression of Sox2 and Klf4 was sufficient to induce pluripotency in the absence of exogenous Oct4, and the stoichiometry of Sox2 and Klf4 was essential. Sox2 and Klf4 cooperatively bound across the genome, leading to epigenetic remodeling of their targets, including pluripotency genes and gradual activation of the pluripotency network. Interestingly, cells of different germ layer origins, fibroblasts (mesoderm) and neural progenitor cells (ectoderm), showed convergent reprogramming trajectories and similar efficiency. This work demonstrates a core function of Sox2 and Klf4 in pluripotency induction and shows that this mechanism is independent of germ layer origin.
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148
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Hao Q, Yang S, Song Z, Li Z, Ding F, Yu C, Hu G, Liu H. Silicon Affects Plant Stoichiometry and Accumulation of C, N, and P in Grasslands. Front Plant Sci 2020; 11:1304. [PMID: 33013953 PMCID: PMC7493684 DOI: 10.3389/fpls.2020.01304] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 08/11/2020] [Indexed: 05/25/2023]
Abstract
Silicon (Si) plays an important role in improving soil nutrient availability and plant carbon (C) accumulation and may therefore impact the biogeochemical cycles of C, nitrogen (N), and phosphorus (P) in terrestrial ecosystems profoundly. However, research on this process in grassland ecosystems is scarce, despite the fact that these ecosystems are one of the most significant accumulators of biogenic Si (BSi). In this study, we collected the aboveground parts of four widespread grasses and soil profile samples in northern China and assessed the correlations between Si concentrations and stoichiometry and accumulation of C, N, and P in grasses at the landscape scale. Our results showed that Si concentrations in plants were significantly negatively correlated (p < 0.01) with associated C concentrations. There was no significant correlation between Si and N concentrations. It is worth noting that since the Si concentration increased, the P concentration increased from less than 0.10% to more than 0.20% and therefore C:P and N:P ratios decreased concomitantly. Besides, the soil noncrystalline Si played more important role in C, N, and P accumulation than other environmental factors (e.g., MAT, MAP, and altitude). These findings indicate that Si may facilitate grasses in adjusting the utilization of nutrients (C, N, and P) and may particularly alleviate P deficiency in grasslands. We conclude that Si positively alters the concentrations and accumulation of C, N, and P likely resulting in the variation of ecological stoichiometry in both vegetation and litter decomposition in soils. This study further suggests that the physiological function of Si is an important but overlooked factor in influencing biogeochemical cycles of C and P in grassland ecosystems.
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Affiliation(s)
- Qian Hao
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
| | - Shilei Yang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
| | - Zhaoliang Song
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
| | - Zichuan Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
- Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, China
| | - Fan Ding
- College of Land and Environment, Shenyang Agriculture University, Shenyang, China
| | - Changxun Yu
- Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Guozheng Hu
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongyan Liu
- College of Urban and Environmental Sciences, Peking University, Peking, China
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149
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Chakouri N, Diaz J, Yang PS, Ben-Johny M. Ca V channels reject signaling from a second CaM in eliciting Ca 2+-dependent feedback regulation. J Biol Chem 2020; 295:14948-14962. [PMID: 32820053 DOI: 10.1074/jbc.ra120.013777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/18/2020] [Indexed: 11/06/2022] Open
Abstract
Calmodulin (CaM) regulation of voltage-gated calcium (CaV1-2) channels is a powerful Ca2+-feedback mechanism to adjust channel activity in response to Ca2+ influx. Despite progress in resolving mechanisms of CaM-CaV feedback, the stoichiometry of CaM interaction with CaV channels remains ambiguous. Functional studies that tethered CaM to CaV1.2 suggested that a single CaM sufficed for Ca2+ feedback, yet biochemical, FRET, and structural studies showed that multiple CaM molecules interact with distinct interfaces within channel cytosolic segments, suggesting that functional Ca2+ regulation may be more nuanced. Resolving this ambiguity is critical as CaM is enriched in subcellular domains where CaV channels reside, such as the cardiac dyad. We here localized multiple CaMs to the CaV nanodomain by tethering either WT or mutant CaM that lack Ca2+-binding capacity to the pore-forming α-subunit of CaV1.2, CaV1.3, and CaV2.1 and/or the auxiliary β2A subunit. We observed that a single CaM tethered to either the α or β2A subunit tunes Ca2+ regulation of CaV channels. However, when multiple CaMs are localized concurrently, CaV channels preferentially respond to signaling from the α-subunit-tethered CaM. Mechanistically, the introduction of a second IQ domain to the CaV1.3 carboxyl tail switched the apparent functional stoichiometry, permitting two CaMs to mediate functional regulation. In all, Ca2+ feedback of CaV channels depends exquisitely on a single CaM preassociated with the α-subunit carboxyl tail. Additional CaMs that colocalize with the channel complex are unable to trigger Ca2+-dependent feedback of channel gating but may support alternate regulatory functions.
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Affiliation(s)
- Nourdine Chakouri
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA
| | - Johanna Diaz
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA
| | - Philemon S Yang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Manu Ben-Johny
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA.
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150
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Atkinson CL, van Ee BC, Pfeiffer JM. Evolutionary history drives aspects of stoichiometric niche variation and functional effects within a guild. Ecology 2020; 101:e03100. [PMID: 32443181 DOI: 10.1002/ecy.3100] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 03/27/2020] [Accepted: 04/15/2020] [Indexed: 12/19/2022]
Abstract
Functional traits are characteristics of an organism that represents how it interacts with its environment and can influence the structure and function of ecosystems. Ecological stoichiometry provides a framework to understand ecosystem structure and function by modeling the coupled flow of elements (e.g. carbon [C], nitrogen [N], phosphorus [P]) between consumers and their environment. Animals tend to be homeostatic in their nutrient requirements and preferentially sequester the element in shortest supply relative to demand, and release relatively more of the element in excess. Tissue stoichiometry is an important functional trait that allows for predictions among the elemental composition of animals, their diet, and their waste products, with important effects on the cycling and availability of nutrients in ecosystems. Here, we examined the tissue stoichiometric niches (C:N:P) and nutrient recycling stoichiometries (N:P) of several filter-feeding freshwater mussels in the subfamily Ambleminae. Despite occupying the same functional-feeding group and being restricted to a single subfamily-level radiation, we found that species occupied distinct stoichiometric niches and that these niches varied, in part, as a function of their evolutionary history. The relationship between phylogenetic divergence and functional divergence suggests that evolutionary processes may be shaping niche complementarity and resource partitioning. Tissue and excretion stoichiometry were negatively correlated as predicted by stoichiometric theory. When scaled to the community, higher species richness and phylogenetic diversity resulted in greater functional evenness and reduced functional dispersion. Filter-feeding bivalves are an ecologically important guild in freshwater ecosystems globally, and our study provides a more nuanced view of the stoichiometric niches and ecological functions performed by this phylogenetically and ecologically diverse assemblage.
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Affiliation(s)
- Carla L Atkinson
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, 35487, USA
| | - Brian C van Ee
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, 35487, USA
| | - John M Pfeiffer
- National Museum of Natural History, Smithsonian Institution, Washington, D.C., 20560, USA
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