Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.26 (invertase)
4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The determination of mercury(II) ions at the trace level by inhibition of the invertase enzyme-catalysed hydrolysis of sucrose into glucose and fructose coupled to electrochemical batch injection analysis was investigated using two approaches. In the first, the glucose produced was detected by injection of 100 microliters samples into the batch injection cell containing a platinum electrode modified by immobilised glucose oxidase. In the second, the glucose and fructose present in injected samples were oxidised directly at a copper-modified glassy carbon electrode. The experimental parameters were optimised and the degree of enzyme inhibition by mercury(II) ions under both conditions was measured. Mercury concentrations in the ng ml-1 range were determined by these two techniques with low sample and reagent consumption. Comparison is made between the two methods and perspectives as a screening test for field application are indicated.
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PMID:Determination of mercury(II) by invertase enzyme inhibition coupled with batch injection analysis. 1219 51

From the open investigation and laboratory analysis, this paper studied the vegetation state and soil enzyme activities of copper tailing yard of Tongguan mountain. The results showed that there were 34 species of natural colonized plants on copper tailing yard, subordinated to 16 families and 33 genera, and regard herbs as principle, and many for 1-2 years old. The main families were compositae (10 species), gramineae (9 species) and legumineceae (2 species). Hippochaete ramosissimum, which belonged to equisetaceae, had and significant dominant. There were some microcoenses such as Hippochaete ramosissimum + Imperata cylindraca community, Cynodon dactylon + Imperata cylindraca community and Phragmites australis community. But, the vegetation on copper tailing yard was distributed in spot piece and scattered mainly with single species. The activities of three soil enzymes had a stronger sensitivity to the vegetation state, and their relativity to the vegetation state was in order of urease > sucrase > catalase. It's suggested that unrease activity could be used as an indicator index for the reclamation of wasteland.
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PMID:[Vegetation state and soil enzyme activities of copper tailing yard on Tongguan mountain]. 1292 35

Studies on the soil microbes, soil enzyme activity and soil biochemical intensity in copper mining wasteland indicated that the total quantity of major soil microbes declined by 68.43%-80.32%, compared with that of the non-minig soil. The proportion of bacteria and actinomyces decreased, while that of fungi did not changed obviously. The amount of major physiological groups including ammonifiers, nitrogen fixing bacteria, cellulose decomposing bacteria, aerobic nitrogen fixing bacteria and anaerobic nitrogen fixing bacteria all decreased, and soil basic respiration descended, compared with the control. The activity of soil enzymes weakened, which included urease, sucrase, proteinase, acid phosphtase, peroxidase, polyphenol oxidase and dehydrogenase. Soil biochemical intensity including ammonification, nitrification, nitrogen fixation and cellulose decomposition descended, and the circulation of C and N in mining soil inhibited. All the results showed that the weakening of microbial activity was one of major characteristics in reclaimed mining soil.
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PMID:[Microbial eco-characteristics of reclaimed mining wasteland in red soil area of southern China. I. Effects on soil microbial activity]. 1499 48

The main effects of pollutions including acid rain, Cu2+, atrazine and their combined products on the activities of urease, invertin, acid phosphatase and catalase were studied by means of orthogonal test. The results showed that H+ and Cu2+ had significant influence on the activities of four enzymes and the ability of their inhibiting followed the order: H+ > Cu2+. Al3+ and atrazine only had litter effects on the activity of urease and phosphatase, respectively. Furthermore, interaction analysis revealed that Cu2+ -H+ affected on the activity of acid phosphatase significantly and antagonism on invertin and urease, Cu2+ -atrazine only exhibited the synergism on the activity of acid phosphatase. But atrazine-H+ had non-interaction within the investigated concentration range. Among four enzymes, acid phosphatase was the most sensitive one to the contaminations.
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PMID:Effect of organic/inorganic compounds on the enzymes in soil under acid rain stress. 1513 33

The effects of acid rain, Cu2+ and atrazine on the activities of soil urease, invertase and acid phosphatase were studied by means of orthogonal test. The results showed that the inhibition rate was H+ > Cu2+, and atrazine had no significant influence on urease and intertase. Interaction analysis revealed that Cu x atrazine exhibited synergism on soil acid phosphatase activity, Cu x H had antagonism on soil invertase and urease, but atrazine x H had no interaction within the investigated concentration range. Among the three enzymes, soil acid phosphatase was the most sensitive one to the contaminations.
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PMID:[Effect of acid rain, copper, and atrazine on soil hydrolase activity]. 1513 4

An endoinulinase produced by Chaetomium sp. C34 was purified to electrophoretic homogeneity, with recovery of 7.7% activity and purification factor of 30.8 fold by five steps including ammonium sulfate precipitation, DEAE-cellulose, Q-sepharose Fast Flow, Sephacryl S-200 and Pre-Packed Hydrophobic Column. Its subunit molecular weight was estimated to be about 66kD by SDS-PAGE. The optimum temperature and pH of the enzyme activity were 50 approximately 55 degrees C and 6.0 respectively. The K(m) and V(max) values for inulin were 0.199 mmol/L and 115 micromol/(mg x min) respectively. Cu2+ completely inhibited inulinase activity. An appreciable loss of activity was observed in presence of NBS, Mn2+, Zn2+, Fe2+ and EDTA. A ratio of inulinase activity to invertase activity (I/S) of 20 was found in purified inulinase. The endoinulinase hydrolyzed inulin and liberated inulooligosaccharides. But it lacked activity toward melezitose or raffinose.
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PMID:[Purification and properties of endoinulinase from Chaetomium sp]. 1611 Sep 61

The study on the calatase, polyphenol-oxidase, invertase, urease and phosphatase activities in Paeonia ostii rhizosphere and non-rhizosphere soil of Tongling copper mining showed that all test enzyme activities were higher in rhizosphere than in non-rhizosphere soil. Soil calatase, urease and phosphatase were sensitive to heavy metals pollution, and their activities could be used as the indicators of heavy metals' joint pollution. The effects of rhizosphere environment on the soil enzyme activities were in the sequence of phosphatase > urease > calatase > invertase > polyphenol-oxidase, and the affecting rate was 131.562%, 92.492%, 87.557%, 59.673% and 34.076%, respectively. The test enzyme activities were negatively correlated with soil heavy metals pollution, and the correlation coefficients were all higher than -0.898, suggesting the inhibitory effects of heavy metals' joint pollution on soil enzyme activities. P. ostii could effectively improve soil environment, and thus, enhance the activities of soil enzymes.
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PMID:[Enzyme activities in Paeonia ostii rhizosphere and non-rhizosphere soil of Tongling copper mining]. 1704 14

The current study was conducted to investigate the effects of high dietary concentrations of Zn as zinc oxide and Cu as copper sulfate on the activity of digestive enzymes in the pancreas and the intestinal mucosa, intestinal morphology, and mucin histochemistry in pigs after weaning. Thirty-two pigs were weaned at 4 wk of age. The pigs were fed standard weaning diets supplemented with Zn (100 or 2,500 ppm) and Cu (0 or 175 ppm) in a 2 x 2 factorial arrangement of treatments for a 14-d period. In pancreatic tissue, the activity of amylase, carboxypeptidase A, chymotrypsin, trypsin, and lipase increased (P < 0.01) in pigs fed 2,500 ppm of Zn, whereas the activity of carboxypeptidase B and carboxylester hydrolase was unaffected. Copper had no effect on the activity of pancreatic enzymes. In small intestinal contents, the total activity of amylase and carboxypeptidase A was greater in pigs fed 100 ppm of Zn (P < 0.05), whereas feeding 2,500 ppm of Zn increased the chymotrypsin activity (P < 0.001). The remaining enzymes were unaffected by dietary Zn concentration. The villi were longer in the cranial small intestine (P < 0.001) in pigs fed 100 ppm of Zn than in pigs fed 2,500 ppm of Zn, but otherwise there were no clear effects of Zn and Cu supplementation on intestinal morphology. In the cranial small intestine, the activity of maltase (P < 0.001), sucrase (P < 0.001), and lactase was greater in pigs fed 100 ppm of Zn, even though there was a Zn x Cu interaction (P < 0.05) in lactase activity. In the middle and caudal small intestine, no clear differences between dietary treatments were observed. The activity of gamma-glutamyl transpeptidase in the intestinal mucosa was not affected by dietary Zn or Cu. In pigs fed 100 ppm of Zn, the activity of aminopeptidase N was greater in the caudal small intestine, but dietary Zn or Cu had no effect on aminopeptidase N in the cranial and middle small intestine. No effect of dietary Zn or Cu supplementation was found on carbohydrate histochemistry in the caudal small intestine, whereas high dietary Zn increased the area of neutral, acidic, and sulfomucins in the cecum (P < 0.01) and in the colon (P < 0.001). In summary, high dietary Zn increased the activity of several enzymes in the pancreatic tissue and increased the mucin staining area in the large intestine, whereas Cu had no clear effect on these variables. However, no definite answers were found as to how the growth promoting and diarrhea reducing effects of excess dietary Zn are exerted.
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PMID:Influence of dietary zinc and copper on digestive enzyme activity and intestinal morphology in weaned pigs. 1709 23

There has been no study on key enzymes in sucrose cleavage in metallophyte plants so far, which may be crucial for the plants' root growth and heavy metal tolerance maintenance. Acid invertases are rate-limiting enzymes in sucrose metabolism. Here, we tested the hypothesis that the roots of copper-tolerant plants should manifest a higher activity of acid invertases than nontolerant plants both for supporting growth and for their maintaining tolerance under Cu stress. Two populations of Rumex dentatus L., one from an ancient waste heap at a Cu mine (Cu-tolerant population), and the other from a noncontaminated site (Cu nontolerant population), were used in the experiments. The seedlings of Rumex dentatus L. were exposed to 0, 10, and 40 microM CuCl(2) for 14 days. Cu exposure had a stronger inhibition on root growth and thus resulted in a lower root/shoot ratio in the plants of nontolerant population compared with the Cu-tolerant population. Cu exposure showed a stronger inhibition of acid invertase activity of Cu nontolerant plants than Cu tolerant plants, whereas neutral/alkaline invertase was insensitive to Cu. A positive correlation between the activity of acid invertases and the root growth and root/shoot ratio was observed. The results suggested that the higher activities in acid invertases of Cu-tolerant population might at least partly associate with the plants' Cu tolerance, and their higher activities in acid invertases in turn played an role in maintenance of the Cu tolerance by supplying carbon and energy for tolerance mechanisms.
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PMID:Effect of Cu stress on the invertase activity and root growth in two populations of Rumex dentatus L. with different Cu tolerance. 1821 87

The electrochemical oxidation of mono- and disaccharides at various copper-modified electrodes is reported: glassy carbon modified at open circuit or by electrochemical deposition of copper, gold modified by electrochemical deposition, and at bulk copper electrodes. A comparative study of these four electrodes was made by linear sweep voltammetry and amperometry. The maximum oxidation peak separation between disaccharides and monosaccharides is about 200mV. After optimization, amperometric determination of monosaccharides was done at +0.30 versus Ag/AgCl in 0.15M NaOH at the copper-modified gold electrode. Using the developed method, the enzymatic activities of invertase and beta-galactosidase were determined through their reaction with sucrose and lactose, respectively. Validation was carried out by a spectrophotometric method based on 3,5-dinitrosalicylic acid, and it was shown that the proposed electrochemical method is more sensitive. The analytical utility of the copper-modified gold electrode was tested for the determination of organic mercury. Addition of phenylmercury standards to the invertase solution caused a decrease in the enzyme activity, and allowed the determination of phenylmercury in pharmaceutical samples. The concentration has been determined in the 10-55ngml(-1) range.
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PMID:Copper-modified gold electrode specific for monosaccharide detection Use in amperometric determination of phenylmercury based on invertase enzyme inhibition. 1896 85


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