Imbalance Of Elements Research Articles

Research progress on correlations between trace element levels and epilepsy.

Research investigating the correlation between human trace element levels and disease alterations is growing. Epilepsy, a common nervous system disease, has also been found to be closely related to abnormal levels of trace elements. Studies continue to explore mechanisms of various trace elements involved in epileptic seizures through experimental animal models of epilepsy. Thus, we reviewed the research progress on the correlation between trace element levels and epilepsy in recent years and found that the trace elements most closely related to epilepsy are mainly metal ions such as selenium, iron, copper, zinc, and manganese. These results indicate that the changes in some trace elements are closely related to the increase in epilepsy susceptibility. In addition, after treatment with drugs and a ketogenic diet, the concentration of trace elements in the serum of patients with epilepsy changes. In other words, the abnormality of trace element concentrations is of great significance in the occurrence and development of epilepsy. This article is a literature update on the potential role of trace element imbalance in the development of epilepsy, providing new references for the subsequent prevention and treatment of epilepsy.

Co-exposure to molybdenum and cadmium evokes necroptosis and decreases apoptosis in duck myocardium

Superfluous molybdenum (Mo) and cadmium (Cd) in the environment are detrimental to organisms through their accumulation. The NF-κB/TNF-α axis plays a vital part in regulating necroptosis and apoptosis. However, the impacts of Mo and/or Cd on myocardium injury in ducks and the function of NF-κB/TNF-α axis are not clear in the process. In this research, ducks exposed to different dosages of Mo and/or Cd were applied as the study object. The findings substantiated that the accumulation of Mo and/or Cd caused elements imbalance and necroptosis in myocardial tissue. As p-NF-κB/TNF-α expression up-regulated, RIPK1/RIPK3/p-MLKL expression significantly increased in all treatment groups, while the expression of c-caspase-8/3 markedly decreased. Moreover, apoptosis rate obviously decreased in Cd treated groups and clearly elevated in Mo group. Mitochondria-mediated apoptosis was activated by excessive Mo and inhibited by Mo + Cd, but Cd exposure alone had little effect on it. Collectively, our research confirmed that Mo and/or Cd evoked necroptosis via NF-κB/TNF-α axis, and decreased death receptor-mediated apoptosis in duck myocardium, the impacts of Mo and/or Cd on mitochondrial-mediated apoptosis were different. These results are significant for studying toxicology of Mo and/or Cd and preserving the ecosystem.

Evaluation of the effects of three arsenolipids on liver damage based on element imbalance and oxidative damage

AbstractThe International Agency for Research on Cancer has classified semimetal arsenic as a human carcinogen. Arsenic poisoning can severely impact human health. Arsenic can be classified into inorganic and organic arsenic, with arsenolipids (AsLs) belonging to the category of organic arsenic. The primary species of AsLs include arsenic‐containing hydrocarbons (AsHCs), fatty acids, and phospholipids. AsLs are highly abundant in marine organisms and diet may be the primary source of exposure to AsLs. Although increasing evidence shows that AsLs are cytotoxic to humans, the specific toxicity and its mechanism remain unclear. This study aimed to evaluate the hepatotoxicity and possible mechanisms of the toxic effects of AsLs in mice. Three AsLs (AsHC 332, AsHC 346, and AsHC 374) were administered via gavage at a dose of 3 mg/kg for 4 weeks. The results showed that short‐term exposure did not affect the normal growth and development of mice. However, it caused liver damage in mice, mainly by disrupting the metabolism of selenium, copper, zinc, and other elements related to the synthesis of antioxidant enzymes, thereby reducing the activity of antioxidant enzymes and the expression of related genes. The liver damage effect of AsHC 332 was the strongest among the three AsLs.

The assessment of serum trace element levels as the diagnostic biomarkers of functional state of broiler chickens.

Elemental analysis is a useful technique for predicting metabolic disorders in broiler chickens. Elemental imbalances are also important for the development of new methods to diagnose the health status of birds that can be implemented on a farm-wide scale. This study aimed to identify elemental markers related to pre-nosological diagnoses of metabolic disorders in broiler chickens. We compared birds given high-protein, high-carbohydrate, and high-fat diets. A control group received the standard diet recommended by the All-Russian Research and Technological Institute of Poultry, while experimental Group I received a diet with high-protein content, Group II received a diet with high-carbohydrate content, and Group III received a diet with high-fat content. At the end of the experiment, blood samples were taken for biochemical and elemental analysis. Biochemical analysis was carried out using an automated biochemical analyzer, and the levels of trace elements in the serum were assessed using inductively coupled plasma spectrometry. We found that the high-protein diet was accompanied by a decrease in chicken body weight, cholesterol, and several elements (i.e., P, Cr, Cu, Zn, and B) as well as an increase in the levels of Ca, Co, and Si. The high-carbohydrate diet led to a significant increase in glucose levels as well as a decrease in the levels of albumin, triglycerides, and Cr, Mn, Se, I, and Cu. Finally, the high-fat diet led to an increase in body weight, glucose, cholesterol, triglycerides, and the elements Cu, Zn, and Si as well as a decrease in the levels of Mg, Cr, and Fe. The determination of the levels of trace elements such as Co, Cr, Mn, Fe, and Cu in chicken blood serum may be an important indicator of the state of protein, carbohydrate, and lipid metabolism of poultry stock.

Rutin, Puerarin and Silymarin Regulated Aluminum-Induced Imbalance of Neurotransmitters and Metal Elements in Brain of Rats.

Non-specifically binding of aluminum to various substances in the organism can result in toxicity. The accumulation of large amounts of aluminum can cause an imbalance in metal homeostasis and interfere with the synthesis and release of neurotransmitters. Flavonoids have strong metal chelating activity, which can reduce damage to the central nervous system. The purpose of this study was to investigate the protective effect of three representative flavonoids, rutin, puerarin and silymarin, on the brain toxicity induced by long-term exposure to aluminum trichloride (AlCl3). Sixty-four Wistar rats were randomly divided into eight groups (n = 8). The rats in six intervention groups were given 100 or 200 mg/kg BW/day of three different flavonoids for four weeks after a 4-week exposure to 281.40 mg/kg BW/day AlCl3·6H2O, while the rats in the AlCl3-toxicity and control groups were given the vehicle after the period of AlCl3 exposure. The results showed that rutin, puerarin, and silymarin could increase the concentrations of magnesium, iron, and zinc in the brains of the rats. Moreover, the intake of these three flavonoids regulated the homeostasis of amino acid neurotransmitters and adjusted the concentrations of monoamine neurotransmitters to normal levels. Taken together, our data suggest that rutin, puerarin, and silymarin could ameliorate AlCl3-induced brain toxicity in the rats by regulating imbalance of metal elements and neurotransmitters in the brains of rats.

Trace Element Imbalances in Acquired Hepatocerebral Degeneration and Changes after Liver Transplant.

Brain manganese (Mn) accumulation is a key feature in patients with acquired hepatocerebral degeneration (AHD). The role of trace elements other than Mn in AHD needs to be clarified. In this study, using inductively coupled plasma mass spectrometry, we aimed to evaluate blood levels of trace elements in patients with AHD before and after liver transplantation (LT). Trace element levels in the AHD group were also compared with those of healthy controls (blood donors, n = 51). Fifty-one AHD patients were included in the study (mean age: 59.2 ± 10.6 years; men: 72.5%). AHD patients had higher levels of Mn, Li, B, Ni, As, Sr, Mo, Cd, Sb, Tl and Pb and a higher Cu/Se ratio, and lower levels of Se and Rb. Six patients (two women; mean age 55 ± 8.7 years) underwent LT, and there was an improvement in neurological symptoms, a significant increase in the Zn, Se and Sr levels, and a decrease in the Cu/Zn and Cu/Se ratios. In summary, several trace element imbalances were identified in AHD patients. Liver transplantation resulted in the improvement of neurological manifestations and the oxidant/inflammatory status. It is possible that observed changes in trace element levels may play a role in the pathophysiology and symptomatology of AHD.

Effects of preharvest bagging on soft nose disorder in mango (Mangifera indica L. cv. ‘Keitt’) during postharvest

ABSTRACT Internal breakdown is a common physiological disorder in mango growth and development, and ‘Keitt’ mango is sensitive to soft nose disorder. In this study, the effect of preharvest bagging on the occurrence of soft nose disorder of ‘Keitt’ mango was studied. The results showed that the incidence rate of soft nose disorder in bagged mango fruit increased with the increase in the fruit size and storage time, and the contents of mainly mineral elements were also affected by fruit size. The bagging treatment decreased the contents of Ca, N, and K mineral elements and increased the contents of Fe, Cu, Mg, and P. Also, except for Ca, the contents of these elements in the decayed tissues of soft nose fruit were higher than those in the unaffected tissues. Using principal component and correlation coefficient analysis indicated that fruit size was related to the incidence of soft nose and mineral element imbalance rather than the lack of Ca being the main cause for internal breakdown. In conclusion, the preharvest bagging treatment affected mineral element content, and the fruit size of mango also affected the distribution and concentration of the mineral elements.

Further Evidence on Trace Element Imbalances in Haemodialysis Patients-Paired Analysis of Blood and Serum Samples.

Previous studies have shown that haemodialysis patients have an increased risk of trace element imbalances. Most studies have determined the concentration of trace elements in serum only, but most trace elements are not uniformly distributed between plasma and blood cells, which justifies separate analysis of the different compartments. In this study, we determined both the serum and whole blood concentration of a wide panel of trace elements (Li, B, Mn, Co, Ni, Cu, Zn, Se, Rb, Sr, Mo, Cd, Pb) in haemodialysis patients and compared them with those of a control group. Whole blood and serum samples were collected during routine laboratory testing of patients undergoing chronic haemodialysis. For comparison purposes, samples from individuals with normal renal function were also analysed. Statistically significant differences (p < 0.05) were found between the two groups for whole blood concentrations of all analysed elements except Zn (p = 0.347). For serum, the difference between groups was statistically significant for all elements (p < 0.05). This study confirms that patients on haemodialysis tend to present significant trace element imbalances. By determining the concentration of trace elements in both whole blood and serum, it was shown that chronic haemodialysis may affect intra- and extracellular blood compartments differently.

Appropriate Macronutrients or Mineral Elements Are Beneficial to Improve Depression and Reduce the Risk of Depression.

Depression is a common mental disorder that seriously affects the quality of life and leads to an increasing global suicide rate. Macro, micro, and trace elements are the main components that maintain normal physiological functions of the brain. Depression is manifested in abnormal brain functions, which are considered to be tightly related to the imbalance of elements. Elements associated with depression include glucose, fatty acids, amino acids, and mineral elements such as lithium, zinc, magnesium, copper, iron, and selenium. To explore the relationship between these elements and depression, the main literature in the last decade was mainly searched and summarized on PubMed, Google Scholar, Scopus, Web of Science, and other electronic databases with the keywords "depression, sugar, fat, protein, lithium, zinc, magnesium, copper, iron, and selenium". These elements aggravate or alleviate depression by regulating a series of physiological processes, including the transmission of neural signals, inflammation, oxidative stress, neurogenesis, and synaptic plasticity, which thus affect the expression or activity of physiological components such as neurotransmitters, neurotrophic factors, receptors, cytokines, and ion-binding proteins in the body. For example, excessive fat intake can lead to depression, with possible mechanisms including inflammation, increased oxidative stress, reduced synaptic plasticity, and decreased expression of 5-Hydroxytryptamine (5-HT), Brain Derived Neurotrophic Factor (BDNF), Postsynaptic density protein 95(PSD-95), etc. Supplementing mineral elements, such as selenium, zinc, magnesium, or lithium as a psychotropic medication is mostly used as an auxiliary method to improve depression with other antidepressants. In general, appropriate nutritional elements are essential to treat depression and prevent the risk of depression.

Crosstalk between Mfn2-mediated mitochondria associated membranes disorder and autophagy induced by molybdenum and cadmium in sheep heart.

To investigate the crosstalk of mitochondria associated membranes (MAMs) disorder and autophagy co-induced by molybdenum (Mo) and cadmium (Cd) in sheep hearts. A total of 48 sheep were randomly divided into 4 groups: control group, Mo group, Cd group and Mo+Cd group. The intragastric administration lasted for 50 days. The results showed that Mo or/and Cd exposure could cause morphological damage, imbalance of trace elements and antioxidant function, Ca2+ concentration decreased markedly, and significantly increase the contents of Mo or/and Cd in myocardium. Additionally, the mRNA and protein levels of endoplasmic reticulum stress (ERS) related factors and mitochondrial biogenesis related factors were altered by Mo or/and Cd, as well as the content of ATP, inducing ERS and mitochondrial dysfunction. Meanwhile, Mo or/and Cd could lead to the alteration of expression level of MAMs-related genes and proteins, and the distance between mitochondria and endoplasmic reticulum (ER), resulting in MAMs disorder. Moreover, Mo or/and Cd exposure upregulated the mRNA and protein levels of autophagy related factors. In conclusion, our results revealed that Mo or/and Cd exposure caused ERS, mitochondrial dysfunction and structural MAMs disruption, ultimately leading to autophagy in sheep hearts, and the effects of Mo and Cd co-exposure were more obvious.

Variability in terrestrial litter decomposition can be explained by nutrient allocation strategies among soil decomposer communities

Abstract Leaf litter decomposition is a key process for nutrient cycling with broad ecosystem‐level consequences. However, we still cannot explain an important amount of the observed variability in decomposition rates. Therefore, a mechanistic model of how litter quality impacts the metabolic capacity of microbial decomposers to degrade litter at a given rate could improve our understanding of litter decomposition. Elemental imbalances between leaf litter and microbial decomposers can lead to nutrient‐limited decomposition. Microbial decomposers can deal with elemental imbalances via three main physiological mechanisms; by adjusting their carbon use efficiency (i.e. the proportion of assimilated carbon that is not respired), accumulating nitrogen or adjusting extracellular enzyme allocation between carbon (C) and nitrogen (N). Therefore, decomposer communities that adjust to elemental imbalances using these strategies should decompose litter faster than those unable to adjust. In this study, in a reciprocal transplant microcosm, we experimentally evaluated whether differences in the capacity of decomposers to reduce elemental imbalances help explain variability in decomposition rates. We used litter and soils from three coexisting woody species with contrasting litter C:N. Throughout the decomposition experiment, we quantified litter biomass loss, the allocation to β‐1,4‐glucosidase and β‐N‐acetylglucosaminidase (i.e. C and N degrading enzymes), and N accumulation. These data allowed us to identify the main strategies through which decomposers deal with elemental imbalances and their concomitant effects on litter decomposition rates. Our results confirm that litter decomposition rates are strongly controlled by litter quality, but differences in decay rates are a function of C and N demands of decomposers. Here, decomposers dealt with elemental imbalances mainly through N accumulation and, to a lesser extent, through extracellular enzyme allocation and lower carbon use efficiency. However, when enzymatic allocation and N accumulation were insufficient to reduce elemental imbalances, decomposition rates were slower irrespective of litter quality. Finally, we show that the effectiveness of physiological strategies used by decomposers to reduce elemental imbalances will affect decomposition rates, a key ecosystem process. Read the free Plain Language Summary for this article on the Journal blog.

Shifting the paradigm for phosphorus fertilization in the advent of the fertilizer crisis

AbstractCrop production and food security will be challenged by the availability of phosphate rock and its derived phosphorus (P) fertilizers in the coming decades. Croplands around the world have traditionally received huge amounts of P fertilizers. However, P can quickly become unavailable in soil due to its fast adsorption or fixation on the surface of soil particles. Here, we propose the use of microbially mediated mechanisms of soil‐borne populations to solubilize historically accumulated P over years. We argue that microbially mediated solubilization of P can be enhanced through elemental imbalances that intentionally alter the soil carbon:nitrogen:P ratio, enabling a greater P demand by some soil microbial populations. This strategy may potentially reduce our dependence on conventional and exhausting P fertilizers, but the main caveats are also discussed.

Exposure to coal mining can lead to imbalanced levels of inorganic elements and DNA damage in individuals living near open-pit mining sites

Coal mining activities are considered harmful to living organisms. These activities release compounds to the environment, such as polycyclic aromatic hydrocarbons (PAHs), metals, and oxides, which can cause oxidative damage to DNA. In this study, we compared the DNA damage and the chemical composition of peripherical blood of 150 individuals exposed to coal mining residues and 120 non-exposed individuals. Analysis of coal particles revealed the presence of elements such as copper (Cu), aluminum (Al), chrome (Cr), silicon (Si) and iron (Fe). The exposed individuals in our study had significant concentrations of Al, sulfur (S), Cr, Fe, and Cu in their blood, as well as hypokalemia. Results from the enzyme-modified comet assay (FPG enzyme) suggest that exposure to coal mining residues caused oxidative DNA damage, particularly purine damage. Furthermore, particles with a diameter of <2.5 μm indicate that direct inhalation could promote these physiological alterations. Finally, a systems biology analysis was performed to investigate the effects of these elements on DNA damage and oxidative stress pathways. Interestingly, Cu, Cr, Fe, and K are key nodes that intensely modulate these pathways. Our results suggest that understanding the imbalance of inorganic elements caused by exposure to coal mining residues is crucial to understanding their effect on human health.

Effect of Mineral Element Imbalance on Neutrophil Respiratory Burst Function and Inflammatory and Antioxidant Responses in Sheep

This study established a model of mineral element homeostatic imbalance and examined the respiratory burst function of peripheral blood neutrophils and inflammatory and antioxidant indicators before and after the imbalance in sheep. The results showed that after an EDTA injection, the number of activated neutrophils in the peripheral blood was significantly higher than that in the control group (p < 0.01). In addition, the serum IL-6 level was significantly increased (p < 0.05) and matrix metalloproteinase 7 (MMP7) was inhibited (p < 0.05), but returned to a normal level one week after the injection. Tissue inhibitor of metalloproteinase 1 (TIMP1) levels were consistently higher after the injection and significantly higher than in the control group (p < 0.05). CuZn-SOD, TNOS activity, serum creatinine and urea nitrogen levels were significantly higher than before the injection (p < 0.05). Combining the results of previous studies, the EDTA injection altered the metabolism and transcription of peripheral blood neutrophils. These changes enhance the respiratory burst function of neutrophils and alter the status of inflammatory and antioxidant indicators such as IL-6 and CuZn-SOD.

Selection of biopolymer carriers for immobilization of essential elements on their surface

Optimization of food recipes, in order to increase their nutritional and biological value, remains relevant in the modern world. In regions with an identified imbalance of essential elements, correction of the diet of the population is necessary. One of the most effective methods is the enrichment of products with immobilized colloidal structures of the necessary elements on the surface of biopolymer carriers. Sorption immobilization is more often used in the food industry, due to its simplicity, cheapness and efficiency, as well as due to the weak influence of the carrier on the catalytic ability of the dispersed phase. As carriers suitable for the immobilization of elements, first of all, insoluble or gel-forming natural sorbents are suitable. These include: agar, pectin, chitosan, collagen, starch, cellulose, coal and others. The article lists the most suitable methods of immobilization, selected carriers. In order to minimize the negative impact of the dispersion medium, the use of a multicomponent carrier is proposed. This applies to both hydrophobic and hydrophilic compounds. It is possible to combine biopolymers with coal, in order to increase the sorption capacity and antimicrobial properties of the finished surface. In the case of pectin and agar, the thermal reversibility of the carrier can be used to simplify the storage of the finished immobilized structure. Currently, technologies for the immobilization of essential elements on the surface of biopolymer carriers are being developed in order to optimize recipes for culinary products and dishes for the food industry.

The effect of a high-calorie diet on the total content of chemical elements and metal-ligand forms of zinc in the blood serum and liver of Wistar rats

Background. Worldwide, there is a rapid increase in the number of people suffering from various forms of carbohydrate and lipid metabolism disorders. Modern studies show that the transport, distribution, excretion and accumulation of chemical elements in these types of metabolic disorders change in different ways and affect the further functional state of the body differently.The aim. To evaluate the level of macro- and microelements in the blood serum and liver, as well as the content of metal-ligand forms of zinc in the blood serum of a Wistar rat in a high-calorie diet.Materials and methods. Thirty male rats were selected for the experiment, from which two groups were formed: control (n = 15) and experimental (n = 15). The animals of the control group received the basic diet (270 kcal/100 g), and the animals of the experimental group received a high-calorie diet. During the experiment, the caloric content of the diet of the experimental group gradually increased from the caloric content of the total diet. During the study, body weight, biochemical parameters of blood and urine were evaluated. The analysis of macro- and microelements in the samples was carried out using inductively coupled plasma mass spectrometry. Determination of the content of individual zinc compounds in blood serum was carried out using a combination of a chromatograph and a mass spectrometer.Results. It was found that a high-calorie diet led to a decrease in the level of iron, chromium, iodine, zinc, potassium, calcium, and an increase in vanadium in blood serum. In the liver, there was a decrease in the level of lithium and an increase in the level of calcium, vanadium, chromium, iron, zinc, cobalt. When assessing the chemical forms of zinc in the blood serum, a percentage increase in the albumin fraction was recorded against the background of a decrease in amino acid complexes and low-molecular-weight forms of zinc.Conclusion. The data obtained suggest that a high-calorie diet leads to an imbalance of chemical elements, which can serve as one of the triggers for dysregulation of a number of physiological functions of the body.

Ecophysiological response of marine copepods to dietary elemental imbalances

We assessed the effects of nutrient imbalanced diets on the feeding, reproduction and gross-growth efficiency of egg production of the copepod Paracartia grani. The cryptophyte Rhodomonas salina, cultivated under balanced (f/2) and imbalanced growth conditions (N and P limitation), served as prey. Copepod C:N and C:P ratios increased in the imbalanced treatments, particularly under P limitation. Feeding and egg production rates did not differ between the balanced and N-limited treatments but decreased under P limitation. We found no evidence of compensatory feeding in P. grani. C gross-growth efficiency averaged 0.34 in the balanced treatment and declined to values of 0.23 and 0.14 for the N- and P-limited treatments, respectively. Under N limitation, N gross-growth efficiency increased significantly to a mean value of 0.69, likely as a result of increasing the nutrient absorption efficiency. P gross-growth efficiency reached values > 1 under P limitation, involving the depletion of body P. Hatching success was >80%, with no differences among diets. Hatched nauplii, however, had lower size and slower development when the progenitor was fed a P-limited diet. This study highlights the effects of P limitation in copepods, which are more constraining than N, and the presence of maternal effects driven by prey nutritional composition that ultimately may affect population fitness.

Amendments of nitrogen and sulfur mitigate carbon-promoting effect on microbial mercury methylation in paddy soils

The imbalance of nutrient elements in paddy soil could affect biogeochemical processes; however, how the key elements input influence microbially-driven conversion of mercury (Hg) to neurotoxic methylmercury (MeHg) remains virtually unknown. Herein, we conducted a series of microcosm experiments to explore the effects of certain species of carbon (C), nitrogen (N) and sulfur (S) on microbial MeHg production in two typical paddy soils (yellow and black soil). Results showed that the addition of C alone into the soils increased MeHg production approximately 2–13 times in the yellow and black soils; while the combined addition of N and C mitigated the C- promoting effect significantly. Added S also had a buffering effect on C-facilitated MeHg production in the yellow soil despite the extent being lower than that of N addition, whereas this effect was not obvious for the black soil. MeHg production was positively correlated with the abundance of Deltaproteobactera-hgcA in both soils, and the changes in MeHg production were related to the shifts of Hg methylating community resulting from C, N, and S imbalance. We further found that the changes in the proportions of dominant Hg methylators such as Geobacter and some unclassified groups could contribute to the variations in MeHg production under different treatments. Moreover, the enhanced microbial syntrophy with adding N and S might contribute to the reduced C-promoting effect on MeHg production. This study has important implications for better understanding of microbes-driven Hg conversion in paddies and wetlands with nutrient elements input.

Does long-term soil warming affect microbial element limitation? A test by short-term assays of microbial growth responses to labile C, N and P additions.

Increasing global temperatures have been reported to accelerate soil carbon (C) cycling, but also to promote nitrogen (N) and phosphorus (P) dynamics in terrestrial ecosystems. However, warming can differentially affect ecosystem C, N and P dynamics, potentially intensifying elemental imbalances between soil resources, plants and soil microorganisms. Here, we investigated the effect of long-term soil warming on microbial resource limitation, based on measurements of microbial growth (18 O incorporation into DNA) and respiration after C, N and P amendments. Soil samples were taken from two soil depths (0-10, 10-20 cm) in control and warmed (>14 years warming, +4°C) plots in the Achenkirch soil warming experiment. Soils were amended with combinations of glucose-C, inorganic/organic N and inorganic/organic P in a full factorial design, followed by incubation at their respective mean field temperatures for 24h. Soil microbes were generally C-limited, exhibiting 1.8-fold to 8.8-fold increases in microbial growth upon C addition. Warming consistently caused soil microorganisms to shift from being predominately C limited to become C-P co-limited. This P limitation possibly was due to increased abiotic P immobilization in warmed soils. Microbes further showed stronger growth stimulation under combined glucose and inorganic nutrient amendments compared to organic nutrient additions. This may be related to a prolonged lag phase in organic N (glucosamine) mineralization and utilization compared to glucose. Soil respiration strongly positively responded to all kinds of glucose-C amendments, while responses of microbial growth were less pronounced in many of these treatments. This highlights that respiration-though easy and cheap to measure-is not a good substitute of growth when assessing microbial element limitation. Overall, we demonstrate a significant shift in microbial element limitation in warmed soils, from C to C-P co-limitation, with strong repercussions on the linkage between soil C, N and P cycles under long-term warming.

Adaptation to a limiting element involves mitigation of multiple elemental imbalances.

About 20 elements underlie biology and thus constrain biomass production. Recent systems-level observations indicate that altered supply of one element impacts the processing of most elements encompassing an organism (i.e. ionome). Little is known about the evolutionary tendencies of ionomes as populations adapt to distinct biogeochemical environments. We evolved the bacterium Serratia marcescens under five conditions (i.e. low carbon, nitrogen, phosphorus, iron or manganese) that limited the yield of the ancestor compared with replete medium, and measured the concentrations and use efficiency of these five, and five other elements. Both physiological responses of the ancestor, as well as evolutionary responses of descendants to experimental environments involved changes in the content and use efficiencies of the limiting element, and several others. Differences in coefficients of variation in elemental contents based on biological functions were evident, with those involved in biochemical building (C, N, P, S) varying least, followed by biochemical balance (Ca, K, Mg, Na), and biochemical catalysis (Fe, Mn). Finally, descendants evolved to mitigate elemental imbalances evident in the ancestor in response to limiting conditions. Understanding the tendencies of such ionomic responses will be useful to better forecast biological responses to geochemical changes.