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:4.1.2.13 (aldolase)
3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Some physical, catalytic, and regulatory properties of ketopantoate hydroxymethyltransferase (5,10-methylenetetrahydrofolate: alpha-ketoisovalerate hydroxymethyltranferase) from Escherichia coli are described. This enzyme catalyzes the reversible synthesis of ketopantoate (Reaction 1), an essential precursor of pantothenic acid. (1) HC(CH3)2COCOO- + 5,10-methylene tetrahydrofolate f in equilibrium r HOCH2C(CH3)2COCOO- + tetrahydrofolate It has a molecular weight by sedimentation equilibrium of 255,000, a sedimentation coefficient (S20,w) of 11 S, a partial specific volume of 0.74 ml/g, an isoelectric point of 4.4, and an absorbance, (see article), of 0.85. Polyacrylamide gel electrophoresis in sodium dodecyl sulfate and amino acid analyses give a subunit molecular weight of 27,000 and 25,700, respectively; both procedures indicate the presence of 10 identical subunits. The NH2-terminal sequence is Met-Tyr---. The enzyme is stable and active over a broad pH range, with an optimum from 7.0 to 7.6. It requires Mg2+ for activity; Mn2+, Co2+, Zn2+ are progressively less active. The enzyme is not inactivated by borohydride reduction in the presence of excess substrates, i.e. it is a Class II aldolase. Reaction 1f is partially inhibited by concentrations of formaldehyde (0.8 mM) and tetrahydrofolate (0.38 mM) below or near the Km values, apparent Km values are 0.18, 1.1 and 5.9 mM for tetrahydrofolate, alpha-ketoisovalerate, and formaldehyde, respectively. For Reaction 1r, apparent Km values are 0.16 and 0.18 mM, respectively, for ketopantoate and tetrahydrofolate, and the saturation curves for both substrates show positive cooperativity. Forward and reverse reactions occur at similar maximum velocities (Vmax approximately equal to 8 mumol of ketopantoate formed or decomposed per min per mg of enzyme at 37 degrees). Only 1-tetrahydrofolate is active in Reaction 1; d-tetrahydrofolate, folate, and methotrexate were neither active nor inhibitory. However, 1-tetrahydrofolate was effectively replaced with conjugates containing 1 to 6 additional glutamate residues; of these, tetrahydropterolpenta-, tetra-, and triglutamate were effective at lower concentrations than tetrahydrofolate itself; they were also the predominant conjugates of tetrahydrofolate present in E. coli. Alpha-Ketobutyrate, alpha-ketovalerate, and alpha-keto-beta-methylvalerate replaced alpha-ketoisovalerate as substrates; pyruvate was inactive as a substrate, but like isovalerate, 3-methyl-2-butanone and D- or L-valine, inhibited Reaction 1. the transferase has regulatory properties expected of an enzyme catalyzing the first committed step in a biosynthetic pathway. Pantoate (greater than or equal to 500 muM) and coenzyme A (above 1 mM) all inhibit; the Vmax is decreased, Km is increased, and the cooperativity for substrate (ketopantoate) is enhanced. Catalytic activity of the transferase is thus regulated by the products of the reaction path of which it is one component; transferase synthesis is not repressed by growth in the presence of pantothenate.
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PMID:Ketopantoate hydroxymethyltransferase. II. Physical, catalytic, and regulatory properties. 0 63

Blood serum was used of 49 rams and 20 ewew infected with Brucell ovis. The study on the total protein and the protein fractions of rams revealed that there existed gamma-globulinemia, the percent of the gamma-globulin rise showing a positive correlation with the morphologic changes in the testes. The alfa-globulins were found to rise immediately following the experimental infecting of the sheep for about a month, after which they came back to normal. In experimental infection the activity of the alkaline phosphatase, aldolase, glutamate-oxalacetate-transaminase, and glutamate-pyruvate-transaminase of the blood serum showed transient characteristic changes, having, however, no diagnostic value.
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PMID:[Biochemical study of serum from sheep infected with Brucella ovis]. 8 49

Enzyme activity of lactate dehydrogenase, glutamate-oxalacetate and glutamate-pyruvate transaminase, creatine phosphokinase, cholinesterase, alkaline, acid and prostatic phosphatase and aldolase has been studied in a total of 213 subjects, of whom 97 were of good health, 63 had bone tumors and 53 suffered from osteomyelitis. The activities of the majority of the enzymes were found to become significantly changed in comparison with the norm. In both patient groups, the more striking differences being noted in that of osteomyelitis. However, enzymatic activity alone does not allow to differentiate the group of bone tumors from that of osteomyelitis, the differences between these two groups not being of significance in any one of the enzymes followed.
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PMID:Serum enzyme activity in bone tumors and osteomyelitis (LDH, GOT, GPT, CPK, CHE, ALP, AP, PP, ALD). 19 May 48

Spirillum bengal is unable to grow on sugars, but can utilize different organic acids as carbon sources. Dehydrogenase activities were tested with different substrates and were found highest with lactate, glutamate, acetate, succinate and malate. A low aldolase activity was also detectable.
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PMID:Aldolase and dehydrogenase activities in Spirillum bengal. 42 15

In rats, starting from a month or three-months age, stayed for 2 months on a diet with 54 per cent of saccharose in the saliva the activity of hexokinase, aldolase, malate-dehydrogenase, sorbitol-dehydrogenase, glutamate-dehydrogenase, glucose-6-phosphate-dehydrogenase and the content of lactate, pyruvate and glucose were determined. In the activity of significant differences of enzymes and carbohydrate metabolites in the saliva of three- and five-months old rats were not disclosed. Keeping of the one-month rats for 2 months on the saccharose diet increased the activity of enzymes (except for malate-dehydrogenase) and raised the amount of lactate and pyruvate. In five-month rats receiving the saccharose ration starting from three-month age a tendency towars a rising activity of hexoninase and to a falling malate-dehidrogenase activity were noted. The activity of other enzymes and the lactate level remained unchageed. In young rats given a saccharose diet the presence of an enzymatic shift toward intensification of the anaerobic glycolysis was confirmed by change in the isofermentative spectrum of the lactate-dehydrogenase accompanied by a drop of the total amount of aerobic isoenzymes LDG1, LDG2 and also by an excess accumulation of pyruvate and lactate.
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PMID:[Effect of a saccharose diet on the enzymatic activity and the metabolite content from carbohydrate metabolism in the saliva of rats of varying age]. 43 32

Cell-free extracts of Rickettsia typhi were tested for activities of enzymes of the tricarboxylic acid cycle, of glutamate catabolism, and of glycolysis. The organisms were grown in the yolk sacs of chicken embryos, harvested shortly before the time of embryo death, purified by Renografin density gradient centrifugation, and ruptured in a French pressure cell. The following enzymatic activities were demonstrated: high levels of malate dehydrogenase (MDH), moderate levels of glutamate-oxaloacetate transaminase, glutamate, succinate, and isocitrate dehydrogenases, and citrate synthase, and low levels of glutamate-pyruvate transaminase. The specific activities of some of these enzymes were higher when the rickettsiae were harvested at a time of active proliferation, 3 to 4 days prior to embryo death. Rickettsial MDH was differentiated from host MDH by its migration pattern on polyacrylamide gel electrophoresis. The activities of MDH and two other dehydrogenases, demonstrable after the cells had been disrupted, were absent from purified, intact rickettsial preparations. No activity was detected for glucose-6-phosphate, 6-phosphogluconate, glyceraldehyde-3-phosphate, lactate dehydrogenases, phosphoglucose isomerase, fructoaldolase, or pyruvate kinase. Our results suggest that extracts of R. typhi that contain demonstrable enzymes involved in the catabolism of glutamate and tricarboxylic acid cycle intermediates, unlike Coxiella burnetti, lack detectable glycolytic activity.
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PMID:Enzymatic activities of cell-free extracts of Rickettsia typhi. 82 Jun 44

The dermal cells in grey, xanthic, and white goldfish integuments were cytochemically characterized for the following enzymatic activities: tyrosinase, DOPA-oxidase, cytochrome oxidase, monoamine oxidase, peroxidase, non-specific esterase, cholinesterase, NAD-diaphorase, NADP-diaphorase, aryl sulfatase, nucleotide phosphodiesterase, beta-glucuronidase, acid phosphatase, alkaline phosphatase, adenosine triphosphatase, thiamine pyrophosphatase, glucose-6-phosphatase, aldolase, as well as succinate, malate, isocitrate, glutamate, glucose-6-phosphate, 6-phosphogluconate, alpha-glycerophosphate, alcohol, lactate, and beta-hydroxybutyrate dehydrogenases. It was found that the epidermis was a significant barrier to the access of cytochemical reaction substrates. Removal of the epidermal barrier provided dermal cell localizations of enzymatic activities which were reproducible. Further, alterations in reaction times and temperatures from the mammalian methodology provided conditions fe various integumental cells were compared for possible interrelationships. The basic foundations for future work with the dermis of poikilothermic vertebrates on an experimental basis were established. In addition, a previously undescribed non-pigmented dermal cell, the "x"-cell, was found to have enzymatic characteristics similar to both melanophores and lipophores. The "x"-cell may be the common precursor of both types of pigment cells.
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PMID:Cytochemical characterization of goldfish (Carassius auratus L.) dermis with special reference to the pigment cells. 82 86

The activity of the following enzymes in clinically normal newborn calves was investigated: glutamate-oxalacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT), alkaline phosphatase (APh), creatine phosphokinase (CPhK), lactate dehydrogenase (LDH), leucine-aminopeptidase (LAP), aldolase (A), and cholinesterase (ChE). The studies were carried out at the first hour prior to offering colostrum as well as at the 6th, 12th, 24th hr and on the 2nd, 3rd, 4th, 5th, 7th, 10th, 15th, and 20th day following it first intake. Regularly rising values of the enzyme activity up to the 24th hour were observed with APh, GOT, GPT, CPhK, and LAP. The aldolase enzyme (after colostrum had been given for the first time) in all animals showed a statistically significant drop of activity at the 6th hour. The activity of LDH displayed a consistently rising trend up to the end of the experimental period. The cholinesterase activity showed high values immediately following birth, reaching those found in the dams by the end of the observation period.
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PMID:[Dynamics of some serum enzymes in the postnatal development of calves]. 94 95

Plasma glucose and lactate concentrations and glutamate-pyruvate transaminase (SGPT), glutamate-oxalacetic transaminase (SGOT), alkaline phosphatase (AP), aldolase (ALD), creatine phosphokinase (CPK), and hydroxybutyrate dehydrogenase (HBD) activities were determined before, throughout the incubation period, and during the course of a viral-induced diarrhea in the neonatal calf. Hypoglycemia with a glucose concentration less than 40 mg/dl of plasma was observed in 3 of 10 calves. Plasma lactate concentration increased to 1.84 plus or minus 0.1 times normal in 7 and 6 to 7 times normal in 2 of the animals. The major change in both glucose and lactate concentrations during diarrhea occurred during the 24 hours preceding death. Changes in SGPT, SGOT, or AP activities were not observed, indicating the absence of marked hepatic damage. The ALD, CPK, and HBD activities were increased in 2 calves and the CPK alone was increased in 2 others, indicating cardiac and possibly skeletal muscle damage.
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PMID:Changes in plasma glucose and lactate concentrations and enzyme activities in the neonatal calf with diarrhea. 112 76

In order to elucidate the effects of amphotericin B (AMB) on the glycolytic pathway, the metabolism of [1-13C]glucose in glucose-grown repressed Saccharomyces cerevisiae was studied. The cells were aerobically suspended in pyrophosphate solutions of high potassium concentration with or without 10(-6) M amphotericin B and measurements were made using 1H-, 13C-NMR spectroscopy and biochemical methods. The results were compared with those obtained under the same experimental conditions but in a medium rich in sodium salts containing the same antibiotic concentration. In general the presence of 10(-6) M AMB reduces the glucose consumption and the ethanol production while favouring the glycerol and trehalose formation. These effects are greatly reduced when a high K+ concentration was used. The AMB effects on the glucose consumption and the production of ethanol, glycerol and trehalose, observed in a suspension rich in Na+, can be fairly well explained by the leakage of K+ through AMB membrane channels. This outflux induces a substantial decrease in the activity of some K(+)-dependent enzymes, such as aldolase, phosphofructokinase and pyruvate kinase. The intensities of the glutamate C2 and C4 signals are higher with a suspension rich in Na+ than with a suspension rich in K+, suggesting that the Krebs cycle operates more effectively in a solution rich in Na+. In the absence of AMB, the passive diffusion of glycerol through the cell membrane is relatively slow and apparently depends on the ionic external medium: it is more efficient in solutions with a high K+ than with a high Na+ concentration. In the presence of 10(-6) M AMB, the glycerol C1,3 resonance drastically decreases at 20 min and then disappears in the noise. This rapid disappearance suggests that glycerol can easily pass through the pores arising from the interaction of AMB with the membrane sterols. However, the rate of pore formation is slow, independent of the external medium (Na+ or K+) and this process is not completed within 20 min.
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PMID:Comparative study of the effects of amphotericin B on the glucose metabolism in Saccharomyces cerevisiae in K(+)- and Na(+)-rich media. 132 8


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