The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not...The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not only raises sustainability concerns but also contributes to soil acidity.Therefore,the use of organic fertilizer could offer a solution for addressing both issues related to soil acidity and sustainability.The purpose of this study was to investigate the manipulation of soil pH using organic fertilizer for soybean production under acidic stress.The planting medium,consisting of a mixture of topsoil,rice husk charcoal,and organic fertilizer(in a ratio of 2:1:1),was supplemented with 0.5 g of NPK fertilizer as a basal treatment in each planting medium.To regulate the soil acidity to pH 4,we added FeSO_(4) and allowed the mixture to incubate for 30 days.The results demonstrate that the application of three types of organic fertilizers chicken manure(P1),oil palm empty bunch fertilizer(P2),and vermicompost(P3)positively impacts the growth of three soybean varieties.The findings indicate that the application of P2 organic fertilizer can increase vegetative growth almost 50%in soybeans on acidic soil,including plant height,leaf count,and root length.Meanwhile,applying P3 organic fertilizer can boost reproductive growth responses in soybeans on acidic soil,such as pod number(from around 0-4 unit to 42-51 unit),grain number(from around 0-5 unit to 88-90 unit),and grain weight(from around 0-0.37 g to 12-25 g).Organic fertilizer has the potential to regulate soil pH,promoting higher yields of soybeans under acidic stress.展开更多
The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show tha...The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50~200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50~400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.展开更多
The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show ...The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50~200 mg·L^(-1).展开更多
The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527~0 696 (μg·g -...The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527~0 696 (μg·g -1 ) in the above ground portion of spinach, 2 668~3 003 (μg·g -1 ) in the under ground portion of spinach and 229 09~250 30 (μg·g -1 ) in the soil. With the acidity of acid rain increasing, the leaching of REE in plants and soil is strengthened and the amount of REE reduces with decreasing of pH value. After REE are used, though plants show the selective absorption to Ce group elements (especially spraying on leaves), regardless under acid rain stress or using REE or not, the distribution model of REE in the above ground and under ground portion of plants is basically the same with the control. Plants also follow the Oddo Harkins rule of the REE of distribution abundance, light rare earth elements is enriched, the minus of Eu is abnormal and admeasure of Ce is a rich model. The results show that REE in plants mainly come from soil and are affected by it.展开更多
To obtain ready-to-use wine malolactic starter cultures with high viability, the effects of acid stress treatments on the growth, inoculation viability, freeze-drying viability, and membrane fatty acid composition of ...To obtain ready-to-use wine malolactic starter cultures with high viability, the effects of acid stress treatments on the growth, inoculation viability, freeze-drying viability, and membrane fatty acid composition of the native Oenococcus oeni SD-2a strain were studied. The results showed that pH 3.5 and 3.2 adaptive treatments did not strongly decrease cell biomass but increased distinctly inoculation viability and freeze-drying viability. Concerning the membrane fatty acid composition, it was observed that acid stress conditions increased significantly the relative concentration of lactobacillic acid (C19cycl 1) and the unsaturated:saturated fatty acid ratio in cell membrane lipids. We assumed that acid-induced cross protective responses could be used in preparing ready-to-use O. oeni SD-2a malolactic starter cultures, and the accumulation of lactobacillic acid in the membrane of O. oeni SD-2a cells appears as an acid stress response mechanism, which might be related with the enhanced viability.展开更多
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ...Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.展开更多
Oenoccoccus oeni is an alcohol-tolerant, acidophilic lactic acid bacterium with its ability to perform malolactic fermentation in wine, which is of fundamental importance in oenology. As a representative of the wine b...Oenoccoccus oeni is an alcohol-tolerant, acidophilic lactic acid bacterium with its ability to perform malolactic fermentation in wine, which is of fundamental importance in oenology. As a representative of the wine bacterium with remarkable adaptability to the very harsh physicochemical conditions of wine, many studies were carded out for its applied interest and focused mainly on its stress response mechanisms of O. oeni. on both physiological and molecular levels. In this review, three main stress response mechanisms in O. oeni during culturing process were addressed. Of them, various solute transporters and secondary metabolic energy-generating systems were utilized to control the intracellular environment and the energetic status of O. oeni. The changes in cell membrane fatty acid composition profiles and synthesis of stress proteins, especially small heat shock proteins were required for active cell response to maintain membrane integrity and function under stress conditions. The study on stress response of O. oeni played an important role on culture bacteria selection, making inoculation culture and construction of other engineering bacteria.展开更多
Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this stu...Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this study, the expression stabilities of nine common reference genes, including ACT2, 18 S r RNA, APRT, EF-1α, RNA POL II, TUBα, TUBβ, GAPDH and TLF of Agropyron mongolicum, were studied under drought condition. Among them, 18 S r RNA was found to be the most optimum reference gene under drought stress by the analyzing of ge Norm and Norm Finder software. Quantitative expression levels of P5 CS using 18 S r RNA as the reference gene, and proline contents under drought stress in A. mongolicum were further operated, and we found the expression level of P5 CS gene and proline content had a significantly positive relationship(R^2=0.7763, P〈0.05). This study established and validated 18 S r RNA as the reference genes in A. mongolicum under drought stress, providing a powerful tool for the quantitative expression analysis of drought genes in A. mongolicum.展开更多
Potentiodynamic polarization tests and slow strain rate test(SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking(SCC) behavior of 7003 aluminum al...Potentiodynamic polarization tests and slow strain rate test(SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking(SCC) behavior of 7003 aluminum alloy(AA7003) in acid and alkaline chloride solutions under various applied potentials(Ea). The results show that AA7003 is to a certain extent susceptible to SCC via anodic dissolution(AD) at open-circuit potential(OCP) and is highly susceptible to hydrogen embrittlement(HE) at high negative Ea in the solutions with p H levels of 4 and 11. The susceptibility increases with negative shift in the potential when Ea is less than-1000 m V vs. SCE. However, the susceptibility distinctly decreases because of the inhibition of AD when Ea is equal to-1000 m V vs. SCE. In addition, the SCC susceptibility of AA7003 in the acid chloride solution is higher than that in the alkaline solution at each potential. Moreover, the effect of hydrogen on SCC increases with increasing hydrogen ion concentration.展开更多
AIM:To investigate the possible reasons and suggest therapeutic plan of stress-induced intestinal necrosis resulting from the severe trauma.METHODS:Three patients in our study were trapped inside collapsed structures ...AIM:To investigate the possible reasons and suggest therapeutic plan of stress-induced intestinal necrosis resulting from the severe trauma.METHODS:Three patients in our study were trapped inside collapsed structures for 22,21 and 37 h,respectively,The patients underwent 3-4 operations after sustaining their injuries,Mechanical ventilation,intermittent hemodialysis and other treatments were also provided.The patients showed signs of peritoneal irritation on postoperative days 10-38.Small intestinal necrosis was confirmed by emergency laparotomy,and for each patient,part of the small bowel was removed.RESULTS:Two patients who all performed 3 operations died of respiratory complications on the first and second postoperative days respectively.The third patient who performed 4 operations was discharged and made a full recovery.Three patients had the following common characteristics:(1) Multiple severe trauma events with no direct penetrating gastrointestinal injury;(2) Multiple surgeries with impaired renal function and intermittent hemodialysis treatment;(3) Progressive abdominal pain and tenderness,and peritoneal irritation was present on post-traumatic days 10-38;(4) Abdominal operations confirmed segment ulcer,necrosis of the small intestine,hyperplasia and stiffness of the intestinal wall;and(5) Pathological examinations suggested submucosal hemorrhage,necrosis,fibrosis and hyalinization of the vascular wall.Pathological examinations of all 3 patients suggested intestinal necrosis with fistulas.CONCLUSION:Intestinal necrosis is strongly associated with stress from trauma and post-traumatic complications;timely exploratory laparotomy maybe an effective method for preventing and treating stressinduced intestinal necrosis.展开更多
Objective To probe into the protective mechanism of electro-acupuncture (EA) on anti-oxygen stress in dementia-model rats. Methods A total of 30 male SD rats of cleaning grade were randomized into three groups, name...Objective To probe into the protective mechanism of electro-acupuncture (EA) on anti-oxygen stress in dementia-model rats. Methods A total of 30 male SD rats of cleaning grade were randomized into three groups, named sham-operation (n = 10), model (n = 10), model+ EA (n = 10). The dementia-model rat was made with hippocampal GA1 lesions by quinolinic acid (QA). On the second day of modeling, in model+ EA group, EA (3 Hz, 2-4 mA, continuous waves) was applied to "Dàzhuī" (大椎 GV 14) and "Shènshū" (肾俞 BL 23) for 10 min. The capability of learning and memory was evaluated by step-down test to observe the changes of nitric oxide (NO), nitric oxide synthase (NOS) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) of the hippocampal tissues in rats separately by biochemical methods. Results EA improved learning and memory of dementia rats with hippocampal CA1 lesions induced by QA at different degrees. It significantly increased SOD activity, reduced MDA content and improved NO level and NOS activity. Conclusion EA improves significantly the learning and memory of the dementia rats due to hippocampal CA1 lesions induced by QA, which is probably relevant with the anti-oxygen stress of EA.展开更多
High prevalence of non-alcoholic fatty liver disease (NAFLD) and very diverse outcomes that are related to disease form and severity at presentation have made the search for noninvasive diagnostic tools in NAFLD one o...High prevalence of non-alcoholic fatty liver disease (NAFLD) and very diverse outcomes that are related to disease form and severity at presentation have made the search for noninvasive diagnostic tools in NAFLD one of the areas with most intense development in hepatology today.Various methods have been investigated in the recent years,including imaging methods like ultrasound and magnetic resonance imaging,different forms of liver stiffness measurement,various biomarkers of necroinflammatory processes (acute phase reactants,cytokines,markers of apoptosis),hyaluronic acid and other biomarkers of liver fibrosis.Multicomponent tests,scoring systems and diagnostic panels were also developed with the purposes of differentiating non-alcoholic steatohepatitis from simple steatosis or discriminating between various fibrosis stages.In all of the cases,performance of noninvasive methods was compared with liver biopsy,which is still considered to be a gold standard in diagnosis,but is by itself far from a perfect comparative measure.We present here the overview of the published data on various noninvasive diagnostic tools,some of which appear to be very promising,and we address as well some of still unresolved issues in this interesting field.展开更多
Seed germination of plants with various acid-resis tance display different responses to acid rain.To understand the reason why such differences occur,the effects of sim ulated acid rain(pH 2.5-5.0)on the activities of...Seed germination of plants with various acid-resis tance display different responses to acid rain.To understand the reason why such differences occur,the effects of sim ulated acid rain(pH 2.5-5.0)on the activities of peroxidase(POD)and catalase(CAT)during sced ger-mination of rice(O.sativa),wheat(T.aestivurm),and rape(B.chinensis var.oleifera)were investigated.R cesults indi-cated that the maximum change in activities of CAT and POD by acid rain treatment with different acidity and time in relation to the referent treatment without acid rain,was in the order:rice(28.8%,31.7%)<wheat(34.7%,48.3%)<rape(79.3%,50.0%).The pH level for which the treatment with acid rain did not cause signif-cant difference(p<0.05)was in the order:rice(3.5)>wheat(4.0)>rape(5.0).Moreover,the change in activity of POD was higher than that of CAT,which showed that POD was more sensitive to acid rain stress than CAT.The difference in the ability of POD and CAT in removing free radicals was one reason why the germina-tion indexes of these three species behaved differently.展开更多
The success of many enteric bacteria is hinged on the ability to tolerate environmental stress such as extreme acidity. The acid stress response (ASR) has been investigated in many enteric bacteria and has been show...The success of many enteric bacteria is hinged on the ability to tolerate environmental stress such as extreme acidity. The acid stress response (ASR) has been investigated in many enteric bacteria and has been shown to involve variable expression of a broad spectrum of genes involved in transcriptional regulation, metabolism, colonization and virulence; representing a linkage between acid tolerance and pathogenicity. Though the majority of ASR studies have been conducted in laboratory conditions and from the perspective of pathogenicity, the role of environmental reservoirs on acid adaptation has recently emerged as an important aspect of pathogenic microbial ecology. This mini-review profiles ASR in three opportunistic enteric pathogens and synthesizes recent work pertaining to the study of this dynamic response.展开更多
The precise roles of the B-box zinc finger family of transcription factors in plant stress are poorly understood.Functional analysis was performed on AtCOL4,an Arabidopsis thaliana L.CONSTANS-like 4 protein that is a ...The precise roles of the B-box zinc finger family of transcription factors in plant stress are poorly understood.Functional analysis was performed on AtCOL4,an Arabidopsis thaliana L.CONSTANS-like 4 protein that is a putative novel transcription factor,and which contains a predicted transcriptional activation domain.Analyses of an AtCOL4 promoter-b-glucuronidase(GUS) construct revealed substantial GUS activity in whole seedlings.The expression of AtCOL4 was strongly induced by abscisic acid(ABA),salt,and osmotic stress.Mutation in atcol4 resulted in increased sensitivity to ABA and salt stress during seed germination and the cotyledon greening process.In contrast,AtCOL4-overexpressing plants were less sensitive to ABA and salt stress compared to the wild type.Interestingly,in the presence of ABA or salt stress,the transcript levels of other ABA biosynthesis and stress-related genes were enhanced induction in AtCOL4-overexpressing and WT plants,rather than in the atcol4 mutant.Thus,AtCOL4 is involved in ABA and salt stress response through the ABA-dependent signaling pathway.Taken together,these findings provide compelling evidence that AtCOL4 is an important regulator for plant tolerance to abiotic stress.e展开更多
Phospholipids, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PC), phosphatidylserine (PS) and phosphoinositides, have emerged as an importan...Phospholipids, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PC), phosphatidylserine (PS) and phosphoinositides, have emerged as an important class of cellular messenger molecules in various cellular and physiological processes, of which PA attracts much attention of researchers. In addition to its effect on stimulating vesicle trafficking, many studies have demonstrated that PA plays a crucial role in various signaling pathways by binding target proteins and regulating their activity and subcellular localization. Here, we summarize the functional mechanisms and target proteins underlying PA-mediated regulation of cellular signaling, development, hormonal responses, and stress responses in plants.展开更多
The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)...The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)but lacks glutamate decarboxylase.This study assessed the efects of Gad system introduction into A.succinogenes.The recombinant strains gadB-SW and gadBC-SW were constructed by heterologous expression of gadB alone,or gadB together with gadC,respectively.After 1.0 and 1.5 h of acid stress at pH 4.6,cell survival of gadBC-SW was greater than gadB-SW.The growth of gadB-SW and gadBC-SW was both afected by the expression of heterologous proteins and byγ-aminobutyric acid,with gadBC-SW growth reduced at a neutral pH.SA production in acidic conditions was evaluated by a shake fask and by 3-L bioreactor fermentation.The results showed gadBC-SW to increase SA production by 8.4%in shake fask compared to the parent strain,SW.For a 3-L bioreactor batch fermentation under acidic environment,the highest conversion rate of sugar to SA was observed for gadBC-SW,reaching 96%.However,SA concentration by gadBC-SW was only 47 g/L and 31 g/L at pH 6.5 and pH 6.0,respectively.In summary,the introduction of heterologous gadB and gadC into A.succinogenes not only improved acid tolerance but also infuenced the synthesis of SA and added a metabolic burden.展开更多
Plant growth regulators are biologically active signaling molecules that regulate a number of plant physiological processes. Auxin(indole-3-acetic acid) is an important plant growth regulator and is synthesized within...Plant growth regulators are biologically active signaling molecules that regulate a number of plant physiological processes. Auxin(indole-3-acetic acid) is an important plant growth regulator and is synthesized within plant tissues through L-tryptophan(L-TRP)-dependent and-independent pathways. It has been found that plants respond to exogenously applied L-TRP due to insufficient endogenous auxin biosynthesis. The exogenous application of L-TRP is highly significant for normal plant growth and development.L-tryptophan is applied through foliar spray, seed priming, and soil application. Soil-applied L-TRP is either directly taken up by plants or metabolized to auxin by soil microbiota and then absorbed by plant roots. Similarly, foliar spray and seed priming with L-TRP stimulates auxin synthesis within plants and improves the growth and productivity of agricultural crops. Furthermore, L-TRP contains approximately 14% nitrogen(N) in its composition, which is released upon its metabolism within a plant or in the rhizosphere and plays a role in enhancing crop productivity. This review deals with assessing crop responses under the exogenous application of L-TRP in normal and stressed environments, mode of action of L-TRP, advantages of using L-TRP over other auxin precursors, and role of the simultaneous use of L-TRP and auxin-producing microbes in improving the productivity of agricultural crops. To the best of our knowledge, this is the first review reporting the importance of the use of L-TRP in agriculture.展开更多
This paper reported a wine-derived lactic acid bacterium,Lactiplantibacillus plantarum XJ25,which exhibited higher cell viability under acid stress upon methionine supplementation.Cellular morphology and the compositi...This paper reported a wine-derived lactic acid bacterium,Lactiplantibacillus plantarum XJ25,which exhibited higher cell viability under acid stress upon methionine supplementation.Cellular morphology and the composition of the cytomembrane phospholipids revealed a more solid membrane architecture presented in the acid-stressed cells treated with methionine supplementation.Transcriptional analysis showed L.plantarum XJ25 reduced methionine transport and homocysteine biosynthesis under acid stress.Subsequent overexpression assays proved that methio-nine supplementation could alleviate the cell toxicity from homocysteine accumulation under acid stress.Finally,L.plantarum XJ25 employed energy allocation strategy to response environmental changes by balancing the uptake methionine and adjusting saturated fatty acids(SFAs)in membrane.These data support a novel mechanism of acid resistance involving methionine utilization and cellular energy distribution in LAB and provide crucial theoretical clues for the mechanisms of acid resistance in other bacteria.展开更多
文摘The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not only raises sustainability concerns but also contributes to soil acidity.Therefore,the use of organic fertilizer could offer a solution for addressing both issues related to soil acidity and sustainability.The purpose of this study was to investigate the manipulation of soil pH using organic fertilizer for soybean production under acidic stress.The planting medium,consisting of a mixture of topsoil,rice husk charcoal,and organic fertilizer(in a ratio of 2:1:1),was supplemented with 0.5 g of NPK fertilizer as a basal treatment in each planting medium.To regulate the soil acidity to pH 4,we added FeSO_(4) and allowed the mixture to incubate for 30 days.The results demonstrate that the application of three types of organic fertilizers chicken manure(P1),oil palm empty bunch fertilizer(P2),and vermicompost(P3)positively impacts the growth of three soybean varieties.The findings indicate that the application of P2 organic fertilizer can increase vegetative growth almost 50%in soybeans on acidic soil,including plant height,leaf count,and root length.Meanwhile,applying P3 organic fertilizer can boost reproductive growth responses in soybeans on acidic soil,such as pod number(from around 0-4 unit to 42-51 unit),grain number(from around 0-5 unit to 88-90 unit),and grain weight(from around 0-0.37 g to 12-25 g).Organic fertilizer has the potential to regulate soil pH,promoting higher yields of soybeans under acidic stress.
文摘The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50~200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50~400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.
文摘The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50~200 mg·L^(-1).
文摘The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527~0 696 (μg·g -1 ) in the above ground portion of spinach, 2 668~3 003 (μg·g -1 ) in the under ground portion of spinach and 229 09~250 30 (μg·g -1 ) in the soil. With the acidity of acid rain increasing, the leaching of REE in plants and soil is strengthened and the amount of REE reduces with decreasing of pH value. After REE are used, though plants show the selective absorption to Ce group elements (especially spraying on leaves), regardless under acid rain stress or using REE or not, the distribution model of REE in the above ground and under ground portion of plants is basically the same with the control. Plants also follow the Oddo Harkins rule of the REE of distribution abundance, light rare earth elements is enriched, the minus of Eu is abnormal and admeasure of Ce is a rich model. The results show that REE in plants mainly come from soil and are affected by it.
基金financed by the Key Technology R&D Program of Shaanxi Province, China (2005K02-G2)
文摘To obtain ready-to-use wine malolactic starter cultures with high viability, the effects of acid stress treatments on the growth, inoculation viability, freeze-drying viability, and membrane fatty acid composition of the native Oenococcus oeni SD-2a strain were studied. The results showed that pH 3.5 and 3.2 adaptive treatments did not strongly decrease cell biomass but increased distinctly inoculation viability and freeze-drying viability. Concerning the membrane fatty acid composition, it was observed that acid stress conditions increased significantly the relative concentration of lactobacillic acid (C19cycl 1) and the unsaturated:saturated fatty acid ratio in cell membrane lipids. We assumed that acid-induced cross protective responses could be used in preparing ready-to-use O. oeni SD-2a malolactic starter cultures, and the accumulation of lactobacillic acid in the membrane of O. oeni SD-2a cells appears as an acid stress response mechanism, which might be related with the enhanced viability.
文摘Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.
基金Supported by the Scientific Research Fund of North University of ChinaShanxi Scholarship Council of China
文摘Oenoccoccus oeni is an alcohol-tolerant, acidophilic lactic acid bacterium with its ability to perform malolactic fermentation in wine, which is of fundamental importance in oenology. As a representative of the wine bacterium with remarkable adaptability to the very harsh physicochemical conditions of wine, many studies were carded out for its applied interest and focused mainly on its stress response mechanisms of O. oeni. on both physiological and molecular levels. In this review, three main stress response mechanisms in O. oeni during culturing process were addressed. Of them, various solute transporters and secondary metabolic energy-generating systems were utilized to control the intracellular environment and the energetic status of O. oeni. The changes in cell membrane fatty acid composition profiles and synthesis of stress proteins, especially small heat shock proteins were required for active cell response to maintain membrane integrity and function under stress conditions. The study on stress response of O. oeni played an important role on culture bacteria selection, making inoculation culture and construction of other engineering bacteria.
基金supported by the Western Light Project of Chinese Academy of Sciencesthe National Natural Science Foundation of China(31060057)the National Natural Science Foundation of Inner Mongolia,China(2015MS0305)
文摘Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this study, the expression stabilities of nine common reference genes, including ACT2, 18 S r RNA, APRT, EF-1α, RNA POL II, TUBα, TUBβ, GAPDH and TLF of Agropyron mongolicum, were studied under drought condition. Among them, 18 S r RNA was found to be the most optimum reference gene under drought stress by the analyzing of ge Norm and Norm Finder software. Quantitative expression levels of P5 CS using 18 S r RNA as the reference gene, and proline contents under drought stress in A. mongolicum were further operated, and we found the expression level of P5 CS gene and proline content had a significantly positive relationship(R^2=0.7763, P〈0.05). This study established and validated 18 S r RNA as the reference genes in A. mongolicum under drought stress, providing a powerful tool for the quantitative expression analysis of drought genes in A. mongolicum.
基金financially supported by the National Natural Science Foundation of China(No.51371039)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),Jiangsu Province,China
文摘Potentiodynamic polarization tests and slow strain rate test(SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking(SCC) behavior of 7003 aluminum alloy(AA7003) in acid and alkaline chloride solutions under various applied potentials(Ea). The results show that AA7003 is to a certain extent susceptible to SCC via anodic dissolution(AD) at open-circuit potential(OCP) and is highly susceptible to hydrogen embrittlement(HE) at high negative Ea in the solutions with p H levels of 4 and 11. The susceptibility increases with negative shift in the potential when Ea is less than-1000 m V vs. SCE. However, the susceptibility distinctly decreases because of the inhibition of AD when Ea is equal to-1000 m V vs. SCE. In addition, the SCC susceptibility of AA7003 in the acid chloride solution is higher than that in the alkaline solution at each potential. Moreover, the effect of hydrogen on SCC increases with increasing hydrogen ion concentration.
基金Supported by The Fund of the People's Liberation Army Gen-eral Hospital of Chengdu Command,No.2011YG-B24
文摘AIM:To investigate the possible reasons and suggest therapeutic plan of stress-induced intestinal necrosis resulting from the severe trauma.METHODS:Three patients in our study were trapped inside collapsed structures for 22,21 and 37 h,respectively,The patients underwent 3-4 operations after sustaining their injuries,Mechanical ventilation,intermittent hemodialysis and other treatments were also provided.The patients showed signs of peritoneal irritation on postoperative days 10-38.Small intestinal necrosis was confirmed by emergency laparotomy,and for each patient,part of the small bowel was removed.RESULTS:Two patients who all performed 3 operations died of respiratory complications on the first and second postoperative days respectively.The third patient who performed 4 operations was discharged and made a full recovery.Three patients had the following common characteristics:(1) Multiple severe trauma events with no direct penetrating gastrointestinal injury;(2) Multiple surgeries with impaired renal function and intermittent hemodialysis treatment;(3) Progressive abdominal pain and tenderness,and peritoneal irritation was present on post-traumatic days 10-38;(4) Abdominal operations confirmed segment ulcer,necrosis of the small intestine,hyperplasia and stiffness of the intestinal wall;and(5) Pathological examinations suggested submucosal hemorrhage,necrosis,fibrosis and hyalinization of the vascular wall.Pathological examinations of all 3 patients suggested intestinal necrosis with fistulas.CONCLUSION:Intestinal necrosis is strongly associated with stress from trauma and post-traumatic complications;timely exploratory laparotomy maybe an effective method for preventing and treating stressinduced intestinal necrosis.
基金a grant from the National Natural Science Foundation of China ( No.30772836)Education Bureau,Jiangsu Province (06KJD360146)
文摘Objective To probe into the protective mechanism of electro-acupuncture (EA) on anti-oxygen stress in dementia-model rats. Methods A total of 30 male SD rats of cleaning grade were randomized into three groups, named sham-operation (n = 10), model (n = 10), model+ EA (n = 10). The dementia-model rat was made with hippocampal GA1 lesions by quinolinic acid (QA). On the second day of modeling, in model+ EA group, EA (3 Hz, 2-4 mA, continuous waves) was applied to "Dàzhuī" (大椎 GV 14) and "Shènshū" (肾俞 BL 23) for 10 min. The capability of learning and memory was evaluated by step-down test to observe the changes of nitric oxide (NO), nitric oxide synthase (NOS) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) of the hippocampal tissues in rats separately by biochemical methods. Results EA improved learning and memory of dementia rats with hippocampal CA1 lesions induced by QA at different degrees. It significantly increased SOD activity, reduced MDA content and improved NO level and NOS activity. Conclusion EA improves significantly the learning and memory of the dementia rats due to hippocampal CA1 lesions induced by QA, which is probably relevant with the anti-oxygen stress of EA.
文摘High prevalence of non-alcoholic fatty liver disease (NAFLD) and very diverse outcomes that are related to disease form and severity at presentation have made the search for noninvasive diagnostic tools in NAFLD one of the areas with most intense development in hepatology today.Various methods have been investigated in the recent years,including imaging methods like ultrasound and magnetic resonance imaging,different forms of liver stiffness measurement,various biomarkers of necroinflammatory processes (acute phase reactants,cytokines,markers of apoptosis),hyaluronic acid and other biomarkers of liver fibrosis.Multicomponent tests,scoring systems and diagnostic panels were also developed with the purposes of differentiating non-alcoholic steatohepatitis from simple steatosis or discriminating between various fibrosis stages.In all of the cases,performance of noninvasive methods was compared with liver biopsy,which is still considered to be a gold standard in diagnosis,but is by itself far from a perfect comparative measure.We present here the overview of the published data on various noninvasive diagnostic tools,some of which appear to be very promising,and we address as well some of still unresolved issues in this interesting field.
基金This work was supported by the Foundation of State Planning Committee(No.GJX01100626)the Foundation of Science and Technology Committee of Jiangsu Province(Grant No.BG2001045)the Foundation from Key Laboratory of Industrial Biotechnology of Ministry of Education,Jiangnan University of China.
文摘Seed germination of plants with various acid-resis tance display different responses to acid rain.To understand the reason why such differences occur,the effects of sim ulated acid rain(pH 2.5-5.0)on the activities of peroxidase(POD)and catalase(CAT)during sced ger-mination of rice(O.sativa),wheat(T.aestivurm),and rape(B.chinensis var.oleifera)were investigated.R cesults indi-cated that the maximum change in activities of CAT and POD by acid rain treatment with different acidity and time in relation to the referent treatment without acid rain,was in the order:rice(28.8%,31.7%)<wheat(34.7%,48.3%)<rape(79.3%,50.0%).The pH level for which the treatment with acid rain did not cause signif-cant difference(p<0.05)was in the order:rice(3.5)>wheat(4.0)>rape(5.0).Moreover,the change in activity of POD was higher than that of CAT,which showed that POD was more sensitive to acid rain stress than CAT.The difference in the ability of POD and CAT in removing free radicals was one reason why the germina-tion indexes of these three species behaved differently.
文摘The success of many enteric bacteria is hinged on the ability to tolerate environmental stress such as extreme acidity. The acid stress response (ASR) has been investigated in many enteric bacteria and has been shown to involve variable expression of a broad spectrum of genes involved in transcriptional regulation, metabolism, colonization and virulence; representing a linkage between acid tolerance and pathogenicity. Though the majority of ASR studies have been conducted in laboratory conditions and from the perspective of pathogenicity, the role of environmental reservoirs on acid adaptation has recently emerged as an important aspect of pathogenic microbial ecology. This mini-review profiles ASR in three opportunistic enteric pathogens and synthesizes recent work pertaining to the study of this dynamic response.
基金supported in part by a grant to C.S.K.from the Next-Generation Bio Green21 program (SSAC,PJ00949104)funded by the Rural Development Administration+1 种基金Basic Science Research Programfunded by the Ministry of Education,Science and Technology of Korea (NRF-2010-0022026)
文摘The precise roles of the B-box zinc finger family of transcription factors in plant stress are poorly understood.Functional analysis was performed on AtCOL4,an Arabidopsis thaliana L.CONSTANS-like 4 protein that is a putative novel transcription factor,and which contains a predicted transcriptional activation domain.Analyses of an AtCOL4 promoter-b-glucuronidase(GUS) construct revealed substantial GUS activity in whole seedlings.The expression of AtCOL4 was strongly induced by abscisic acid(ABA),salt,and osmotic stress.Mutation in atcol4 resulted in increased sensitivity to ABA and salt stress during seed germination and the cotyledon greening process.In contrast,AtCOL4-overexpressing plants were less sensitive to ABA and salt stress compared to the wild type.Interestingly,in the presence of ABA or salt stress,the transcript levels of other ABA biosynthesis and stress-related genes were enhanced induction in AtCOL4-overexpressing and WT plants,rather than in the atcol4 mutant.Thus,AtCOL4 is involved in ABA and salt stress response through the ABA-dependent signaling pathway.Taken together,these findings provide compelling evidence that AtCOL4 is an important regulator for plant tolerance to abiotic stress.e
基金supported by the National Natural Science Foundation of China(31721001 and 31400261)the“Ten Thousand Talent Program”Collaborative Innovation Center of Crop Stress Biology,Henan Province
文摘Phospholipids, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PC), phosphatidylserine (PS) and phosphoinositides, have emerged as an important class of cellular messenger molecules in various cellular and physiological processes, of which PA attracts much attention of researchers. In addition to its effect on stimulating vesicle trafficking, many studies have demonstrated that PA plays a crucial role in various signaling pathways by binding target proteins and regulating their activity and subcellular localization. Here, we summarize the functional mechanisms and target proteins underlying PA-mediated regulation of cellular signaling, development, hormonal responses, and stress responses in plants.
基金The authors are grateful for the fnancial support from the National First-class Discipline Program of Light Industry Technology and Engineering(Grant No.LITE2018-04)the Topnotch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP).
文摘The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)but lacks glutamate decarboxylase.This study assessed the efects of Gad system introduction into A.succinogenes.The recombinant strains gadB-SW and gadBC-SW were constructed by heterologous expression of gadB alone,or gadB together with gadC,respectively.After 1.0 and 1.5 h of acid stress at pH 4.6,cell survival of gadBC-SW was greater than gadB-SW.The growth of gadB-SW and gadBC-SW was both afected by the expression of heterologous proteins and byγ-aminobutyric acid,with gadBC-SW growth reduced at a neutral pH.SA production in acidic conditions was evaluated by a shake fask and by 3-L bioreactor fermentation.The results showed gadBC-SW to increase SA production by 8.4%in shake fask compared to the parent strain,SW.For a 3-L bioreactor batch fermentation under acidic environment,the highest conversion rate of sugar to SA was observed for gadBC-SW,reaching 96%.However,SA concentration by gadBC-SW was only 47 g/L and 31 g/L at pH 6.5 and pH 6.0,respectively.In summary,the introduction of heterologous gadB and gadC into A.succinogenes not only improved acid tolerance but also infuenced the synthesis of SA and added a metabolic burden.
文摘Plant growth regulators are biologically active signaling molecules that regulate a number of plant physiological processes. Auxin(indole-3-acetic acid) is an important plant growth regulator and is synthesized within plant tissues through L-tryptophan(L-TRP)-dependent and-independent pathways. It has been found that plants respond to exogenously applied L-TRP due to insufficient endogenous auxin biosynthesis. The exogenous application of L-TRP is highly significant for normal plant growth and development.L-tryptophan is applied through foliar spray, seed priming, and soil application. Soil-applied L-TRP is either directly taken up by plants or metabolized to auxin by soil microbiota and then absorbed by plant roots. Similarly, foliar spray and seed priming with L-TRP stimulates auxin synthesis within plants and improves the growth and productivity of agricultural crops. Furthermore, L-TRP contains approximately 14% nitrogen(N) in its composition, which is released upon its metabolism within a plant or in the rhizosphere and plays a role in enhancing crop productivity. This review deals with assessing crop responses under the exogenous application of L-TRP in normal and stressed environments, mode of action of L-TRP, advantages of using L-TRP over other auxin precursors, and role of the simultaneous use of L-TRP and auxin-producing microbes in improving the productivity of agricultural crops. To the best of our knowledge, this is the first review reporting the importance of the use of L-TRP in agriculture.
基金supported by the National Natural Science Foundation of China(32072206)the National Key R&D Program of China(2019YFD1002503)the China Technology Agriculture Research System(CARS-29-jg-3).
文摘This paper reported a wine-derived lactic acid bacterium,Lactiplantibacillus plantarum XJ25,which exhibited higher cell viability under acid stress upon methionine supplementation.Cellular morphology and the composition of the cytomembrane phospholipids revealed a more solid membrane architecture presented in the acid-stressed cells treated with methionine supplementation.Transcriptional analysis showed L.plantarum XJ25 reduced methionine transport and homocysteine biosynthesis under acid stress.Subsequent overexpression assays proved that methio-nine supplementation could alleviate the cell toxicity from homocysteine accumulation under acid stress.Finally,L.plantarum XJ25 employed energy allocation strategy to response environmental changes by balancing the uptake methionine and adjusting saturated fatty acids(SFAs)in membrane.These data support a novel mechanism of acid resistance involving methionine utilization and cellular energy distribution in LAB and provide crucial theoretical clues for the mechanisms of acid resistance in other bacteria.