scholarly journals Sucrose-Enzyme Relationships in Immature Sugarcane Treated With Variable Molybdenum, Calcium, Iron, Boron, Lead, Trichloroacetic Acid, Beta-glycerophosphate, and Starch

1969 ◽  
Vol 49 (4) ◽  
pp. 443-461
Author(s):  
Alex G. Alexander

Variable levels of the elements molybdenum, calcium, iron, lead, and boron, as well as trichloroacetic acid, ß-glycerophosphate, and starch, were supplied to immature sugarcane grown in the greenhouse. Molybdenum, calcium, and iron were provided in factorial combination to plants in sand culture. Molybdenum, lead, and starch were applied as foliar sprays to a second group of plants grown in soil, and boron, ß-glycerophosphate, plus trichloroacetic acid were likewise applied to the foliage of plants grown in soil. The objectives of these experiments were to determine whether any of the applied materials could alter the action of specific enzymes, and, if so, whether significantly greater sucrose content would result. Leaf and meristem tissues were assayed for sugars, and for the enzymes amylase, invertase, acid phosphatases, starch phosphorylase, peroxidase, and polyphenol oxidase. Molybdenum significantly increased sucrose when applied as a foliar spray (80 p.p.m.), and as a nutrient in sand culture (1 p.p.m.). The molybdenum effect was retarded or reversed when either high calcium (9 p.p.m.) or high iron (6 p.p.m.) was supplied concurrently. Acid phosphatases and amylase were suppressed by high molybdenum, although these effects were greatly dependent upon calcium and iron supply. When applied as a foliar spray, molybdenum suppressed amylase and the phosphatase hydrolyzing glucose-1-phosphate, but not ATP-ase or ß-glycerophosphatase. Invertase was suppressed by high iron (6 p.p.m.) when molybdenum and calcium were low, but was stimulated when molybdenum was high. Lead, when applied to leaves at the rate of 50 p.p.m., caused moderate sucrose increases. Glucose-1-phosphate phosphatase was suppressed by lead in leaves and meristem, as was starch phosphorylase in the leaves. Foliar starch application failed to stimulate amylase, while ß-glycerophosphate failed to inhibit starch phosphorylase or to induce greater phosphatase activity. A number of enzyme responses were obtained which do not happen in vitro, and known in vitro effects did not always appear when specific materials were applied to living plants. Trichloroacetic acid, in particular, appeared to stimulate rather than inhibit enzyme action in vivo. This and other consequences of applying enzyme-regulating materials are discussed in detail.

1969 ◽  
Vol 49 (4) ◽  
pp. 429-442
Author(s):  
Alex G. Alexander

Variable concentrations of tungsten and molybdenum were applied as foliar sprays to 12-week-old sugarcane grown in sand culture. The objectives were to evaluate both elements as in vivo inhibitors of amylase, invertase, and acid phosphatases, and to test further the hypothesis that such inhibition will result in increased sucrose content. Leaf and meristem samples were harvested just prior to initial treatment, and at 3, 9, and 27 days thereafter. Glucose-1-phosphatase and amylase were generally inhibited by both elements, and increased sucrose usually appeared as a consequence. Tungsten at 10 p.p.m. significantly increased sucrose in leaf and meristem at all posttreatment harvests. Molybdenum was a more effective phosphatase inhibitor than tungsten, but was less effective in promoting sucrose production. Molybdenum increased sucrose in meristem only. ß-glycerophosphatase and ATP-ase were stimulated by some of the treatments. This was totally unexpected since both enzymes are known to be inhibited by tungsten and molybdenum in vitro. Certain treatments appeared to reduce the enzymes' capacity to experience major fluctuations. The significance of this property and the stimulation of ATP-ase are discussed at length.


Weed Science ◽  
1980 ◽  
Vol 28 (3) ◽  
pp. 334-340 ◽  
Author(s):  
Luanne M. Deal ◽  
J. T. Reeves ◽  
B. A. Larkins ◽  
F. D. Hess

The effects of chloracetamides on protein synthesis were studied both in vivo and in vitro. Four chloracetamide herbicides, alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide], metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide], CDAA (N–N-diallyl-2-chloroacetamide), and propachlor (2-chloro-N-isopropylacetanilide) were tested for inhibition of [3H]-leucine incorporation into protein. Incorporation of3H-leucine into trichloroacetic acid (TCA)-insoluble protein was inhibited in oat (Avena sativaL. ‘Victory’) seedlings grown in sand culture and treated 12 h at 1 × 10−4M with these chloracetamides. The herbicides were also tested in a cell-free protein synthesizing system containing polyribosomes purified from oat root cytoplasm. These herbicides had no effect on the rates of polypeptide elongation nor on the synthesis of specific polypeptides when herbicides (1 × 10−4M) were added directly to the system. Polypeptide formation was inhibited 89% when 1 × 10−4M cycloheximide was added during translation. Cytoplasmic polyribosomes were isolated from oat roots treated 12 h with 1 × 10−4M herbicide. Translation rates and products were not altered when these polyribosomes were added to the in vitro system. Protein synthesis is inhibited when tested in an in vivo system; however, the inhibition does not occur during the translation of mRNA into protein.


2020 ◽  
Vol 10 (15) ◽  
pp. 5183
Author(s):  
Jain Nam ◽  
Kyeong Jin Kim ◽  
Geonhee Park ◽  
Byeong Goo Kim ◽  
Gwi-Hwa Jeong ◽  
...  

This study aimed to determine the effect of deep-sea water (DSW)-derived mineral waters on intestinal health, using a cell model and a dextran sulfate sodium (DSS)-induced enteritis mouse model. DSW was desalted and minerals were added to generate mineral waters that were classified as trace mineral (TM), high magnesium (HM), high magnesium low salt (HMLS), and high magnesium high calcium (HMHC), using a tabletop electrodialysis device. Caco-2 cells cocultured with Raw264.7 cells were either pre-treated or not with the four water groups, and inflammation was induced by treatment with lipopolysaccharide (LPS). Compared to LPS-treated Caco-2 cells, HMLS-cotreated cells maintained high transepithelial electrical resistance, similar to control cells. FITC-dextran permeability was lower in HMLS-treated than in other cells. In vivo, in comparison to DSS-treated mice, colon shortening was inhibited, and disease activity and colon injury were suppressed in HMLS-cotreated mice. RNA-seq of colonic tissues revealed that inflammatory gene expression was similar among the control and HMLS mice, and DSS-induced expression of inflammation-related genes such as TNF-α and NOS2 and inflammatory chemokine genes was suppressed. Our findings suggest that DSW-derived mineral water intake can help reduce colitis symptoms, and the effects may be partially regulated by magnesium and other minerals.


Author(s):  
Alex G. Alexander ◽  
Rafael Montalvo-Zapata

Sugarcane studies have shown that the desiccants Paraquat and Diquat cause severe sucrose losses as a result of interrupted photosynthesis and abnormal behavior of sugar-metabolizing enzymes. It was theorized that an appropriate agent, selective for the sucrose-limiting enzymes, could modify the sugar-destroying features of otherwise useful chemicals. Experiments are reported herein in which silicon (Si), an in vitro inhibitor of cane enzymes, was applied to sugarcane foliage prior to treatment with Paraquat and Diquat. There were three objectives: 1, To incorporate sufficient Si into living tissues to control hydrolytic and oxidative enzymes; 2, to help retain photosynthetic activity; and 3, to maintain higher sucrose levels as a consequence of lessened sugar metabolism and continued photosynthesis. Plants of the variety P.R. 980 were grown in sand culture and treated with the following percent solutions of Paraquat and Diquat: 0, 0.0002, 0.0006, 0.0018, 0.0054, and 0.0162. For each experiment half of the plants were pretreated with 500 p.p.m. of Si (Na2SiO3-9H2O) as a foliar spray at 8, 4, and 1 day prior to desiccant application. The following results were obtained: 1. The 0.0018 to 0.0162 percent levels severely damaged cane foliage, desiccated leaves and sheaths, and caused major sucrose losses in plants not pretreated with Si. 2. Si-pretreated plants retained near-normal foliage and near-normal sucrose levels for approximately two Paraquat increments above those of non-pretreated plants. For example, damage typical of the 0.0018 percent level, without Si, did not appear until the 0.0162 percent level was reached when Si was present. 3. Paraquat desiccation, as reflected by sheath-moisture values, was ultimately constant regardless of Si treatment. 4. Paper chromatography revealed ribose in leaf extracts of Paraquat-and Diquat-treated plants. Si pretreatment retarded the appearance of ribose below the 0.0162 percent level of Paraquat, and at all Diquat levels. This indicated a Si "protection" of photosynthetic reactions, possibly those of phosphoribose isomerase. 5. The leaf enzymes phosphatase, ATP-ase, and peroxidase were suppressed by increasing desiccant concentrations. Si pretreatments acted to preserve near normal enzyme levels regardless of desiccant action. Leaf amylase, and invertase from immature storage tissue, were greatly stimulated by Paraquat. In these instances Si served to suppress the excessive enzyme activity. 6. Si did not seem to act as an inhibitor in living tissues, as it is known to do in the test tube. Rather, a series of Si-enzyme complexes appeared to form and to retard activity shifts in either direction. 7. A third experiment involving 0.001 percent Paraquat, and a single Si pretreatment given 1 day prior to Paraquat, generally verified the sucrose, enzyme, and visible foliar effects noted earlier with more severe desiccant and Si treatments. The results support the thesis that undesirable effects of a chemical on plants can be selectively modified by control of critical enzymes. The value of this concept in increasing the scope and productivity of agricultural chemicals is noted.


1997 ◽  
Vol 16 (11) ◽  
pp. 629-635 ◽  
Author(s):  
AP Moghaddam ◽  
R. Abbas ◽  
JW Fisher ◽  
JC Lipscomb

1 Both trichloroethylene and its metabolite, dichloroa cetic acid, produce liver tumors peroxisome prolifera tion and other adverse cellular alterations in rodents. 2 The hepatic mechanism by which dichloroacetic acid is formed is not conclusively demonstrated, but pharmacokinetic models have successfully associated its formation with trichloroacetic acid as immediate precursor. 3 Previous investigations have shown that dichloroace tic acid is formed from trichloroacetic acid by gut microflora isolated in vitro. 4 To determine the impact of gut microflora on dichlor oacetic acid formation from a trichloroethylene dose in vivo, we developed a procedure which reduced gut microflora some 3 orders of magnitude below pub lished levels. 5 The administration of trichloroethylene to control mice and to mice whose gut was practically sterile resulted in equivalent concentrations of dichloroace tic acid and other metabolites in blood and liver, but significantly different content of these metabolites in cecum contents. 6 These data indicate that gut microflora contribute minimally, if at all, to the formation of circulating dichloroacetic acid under these conditions.


2014 ◽  
Vol 35 (2) ◽  
pp. 370-378 ◽  
Author(s):  
Nicole Rietzschel ◽  
Antonio J. Pierik ◽  
Eckhard Bill ◽  
Roland Lill ◽  
Ulrich Mühlenhoff

Iron is an essential, yet at elevated concentrations toxic trace element. To date, the mechanisms of iron sensing by eukaryotic iron-responsive transcription factors are poorly understood. TheSaccharomyces cerevisiaetranscription factor Yap5, a member of the Yap family of bZIP stress response regulators, administrates the adaptive response to high-iron conditions. Despite the central role of the iron-sensing process for cell viability, the molecule perceived by Yap5 and the underlying regulatory mechanisms are unknown. Here, we show that Yap5 senses high-iron conditions by two Fe/S clusters bound to its activator domain (Yap5-AD). The more stable iron-regulatory Fe/S cluster at the N-terminal cysteine-rich domain (n-CRD) of Yap5 is detectedin vivoandin vitro. The second cluster coordinated by the C-terminal CRD can only be shown after chemical reconstitution, since it is bound in a labile fashion. Both clusters are of the [2Fe-2S] type as characterized by UV/visible (UV/Vis), circular dichroism, electron paramagnetic resonance (EPR), and Mössbauer spectroscopy. Fe/S cluster binding to Yap5-AD induces a conformational change that may activate transcription. The cluster-binding motif of the n-CRD domain is highly conserved in HapX-like transcription factors of pathogenic fungi and thus may represent a general sensor module common to many eukaryotic stress response regulators.


1969 ◽  
Vol 49 (2) ◽  
pp. 153-175
Author(s):  
Alex G. Alexander

In order to test the hypothesis that starch formation and metabolism is of importance to the sucrose-forming potential of cane, a series of 4-week-old plants was subjected to treatments designed to cause wide fluctuations in the enzyme starch phosphorylase. Treatments included high and low nitrate to vary acidity, high and low phosphate to vary the ratio of H3PO4 to glucose-1-phosphate, and two varieties (Uba and M.336) with distinct reputations for producing starch and sucrose, respectively. Treatments were supplied in 2 X 2 X 2 factorial combination. Sugar and enzyme assays were conducted with leaf and meristem samples harvested after 8 weeks of treatment. Sugars included total ketose, total reducing sugars, sucrose, fructose, and glucose. Enzymes included sucrose phosphorylase, starch phosphorylase, invertase, amylase, hexokinase, peroxidase, polyphenol oxidase, and a series of acid phosphatases hydrolyzing ß-glycerophosphate, glucose-1-phosphate, glucose-6-phosphate, fructoses- phosphate, 3-phosphoglyceric acid, ATP, and ADP.


2014 ◽  
Vol 52 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Marie Kummerova ◽  
Józef Buczek

The deficieny of inorganic phosphate in nutrient solution reduces by about 50 per cent NO<sub>3</sub>- absorption in corn seedlings, it decreases both <em>in vitro</em> and in vivo nitrate reductase (NR) activity, as well the potential and actual NR level and has a very weak effect on NR induction. Acid phosphatases activities increase in corn roots when the plants are grown in nutrient solution without phosphorus. We suggest that inorganic phosphate is required mainly for maintenance of NR activity rather, than for induction <em>in vivo</em> of nitrate reductase. It is not excluded that deficiency of inorganic phosphate in root tissue may be partly supplemented as the result of enhanced acid phosphatase activity.


Author(s):  
Laxman Prasad Balai ◽  
R. B. Singh ◽  
Asha Sinha ◽  
S. M. Yadav

Efficacy of bio agents and systemic and non-systemic fungicides @ 50, 100, 200, 250 and 500 ppm were evaluated In vitro against Alternaria tenuissima causing Alternaria blight of pigeonpea. The relative efficacy of bio agents were studied in dual culture plate method showed that Hypocrea rufa was found most effective antagonist against test pathogen followed by T. harzianum. Efficacy of six fungicides was tested in poisoned food technique. Among the six fungicides tested, mancozeb was found most effective against test pathogen followed by Chlorothalonil and Iprodione. Propineb was least effective against mycelial growth of test pathogen. Raise in concentration of fungicides was more effective in inhibiting the mycelial growth of the pathogen. Field condition studies were found out to be the effect of seed treatment, foliar spray, seed treatment+ foliar spray with six fungicides and two bio agents and their combination used as against pathogen. Artificial inoculation of mass culture of A. tenuissima was done in the inoculated seed treatment and after foliar spray on the plants sixty DAS. Amongst them twenty five treatments, combination of Mancozeb with H. rufa was found most effective in reducing the disease intensity and disease control followed by Mancozeb with T. harzianum and Mancozeb alone, respectively. While, T. harzianum alone was least effective and maximum disease intensity recorded as a compared to control followed by T. harzianum with double dose and T. harzianum and H. rufa combination treatment, respectively. In case of both seed treatment and foliar spray of Mancozeb with H. rufa was found most effective in reducing the disease intensity and disease control followed by combination of Mancozeb with T. harzianum and Mancozeb alone, respectively. Whereas, least effective and maximum disease intensity and disease control were observed T. harzianum alone as compared to control.


1969 ◽  
Vol 51 (1) ◽  
pp. 46-54
Author(s):  
Alex G. Alexander

Immature sugarcane was treated with chemical additives to determine whether significant and predictable changes could be induced in enzyme behavior. All plants were grown in sand culture with controlled nutrient supply. One group received foliar application of ascorbic acid, cysteine, hydroxylamine and cyanide; the other group received silicon, iron, and cyanide as nutrient-solution supplements. Enzymes assayed included acid phosphatases, invertase, amylase, peroxidase, and tyrosinase (polyphenoloxidase). Each of the chemicals tested was known to affect one or more enzymes in vitro. Plants receiving 1,000 p.p.m. of cyanide as a foliar spray increased sucrose in leaves and meristem within 3 days. All enzymes measured were suppressed by CN. Amylase was markedly stimulated by 50 and 1,000 p.p.m. of cysteine. All the enzymes assayed were moderately stimulated by 50 p.p.m. of cysteine, whereas 1,000 p.p.m. caused general suppression. Plants receiving 200 p.p.m. of cyanide as a nutrient-solution supplement were greatly stunted and revealed low sugar content of leaf and meristem tissues. Tyrosinase was about 3 times more active in high-cyanide plants than in controls. Silicon added to nutrient solutions at rates of 20 and 200 p.p.m. greatly retarded invertase and tyrosinase. This confirms similar observations recorded earlier, and it is suggested that enzyme inhibition is a physiological function of silicon in sugarcane. Iron added to nutrient solutions at the rate of 10 p.p.m. caused general enzyme suppression, particularly with regard to meristem peroxidase and invertase. Significance of enzyme regulation in living cane is briefly discussed.


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