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)

1. The authors report the results obtained after the action of certain optotoxic substances on several enzyme activities in the retina of the pig. 2. This in vitro study involved enzyme interferences of the following optotoxic agents : ethionamide, d-penicillamine, ethylene diaminotetra-acetic acid (EDTA), disodium and dicobalt salts. The enzyme activities studied involved glycolysis, the enzymes selected being as follows: glucose phosphate isomerase (GPI, E.C. 5.3.1.9), fructose-1,6-diphosphate aldolase (F1-6diPA, E.C. 4.1.2.13), lactate dehydrogenase (LDH, E.C. 1.1.1.27). 3. Following the action of the effectors studied, a marked decrease in the enzyme activities examined was found in the retina. This decrease, of varying rapidity and regularity, went as far in some cases as total inhibition; there was disturbance of glycolysis. 4. These results indicate the existence of interactions with a complex mechanism. It may be noted that all of the effectors studied were chelating agents of divalent metals and the changes which they induced in the enzyme activities examined may be explained by interference of the chelates formed with metal cations, such as Zn++, co-factors or effectors of these glycolysis enzymes (with the exception of GPI). These stable chelates are formed by virtue of the primary amine--NH2, thiol--SH, thionyl-[Formula: see text] groups, i.e. groups belonging to molecules essential to cell metabolism.
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PMID:[Effects of optotoxic substances on several glycolytic enzyme activities in the retina of the pig (author's transl)]. 679 28

Clones of 32 strains of Trichomonas vaginalis isolated from patients attending a venereal diseases clinic were compared among themselves and with authentic Pentatrichomonas hominis on the basis of their isoenzyme patterns for eight enzymes by thin-layer starch-gel electrophoresis. The enzymes examined were: glucose phosphate isomerase (GPI); phosphoglucomutase (PGM); malic enzyme (NADP+) (ME); hexokinase (HK); malate dehydrogenase (NAD+) (MDH); glucose-6-phosphate dehydrogenase (G6PD); aldolase (ALD); and lactate dehydrogenase (LDH). From the isoenzyme patterns of four enzymes (LDH, MDH, HK, and GPI) the strains of T vaginalis could be divided clearly into five groups. PGM showed differences in only one strain, while two other enzyme patterns (ME and ALD) were the same for all the strains of T vaginalis tested. All isolates were clearly distinguishable from P hominis. Although G6PD patterns were not sharp some differences were evident among T vaginalis strains.
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PMID:Isoenzyme characterisation of Trichomonas vaginalis. 698 Jun 85

The purification of an enzyme is described, a protease, from human erythrocytes which degrades insulin with a high specificity at physiological hormone concentrations. Since the enzyme contains free sulfhydryl groups, affinity chromatography on organomercuri-Sepharose proved to be applicable as a valuable step in the isolation procedure. The purification factor amounted to approx. 6000, the yield to 8%. 1mg of purified enzyme was capable of degrading 50 pmol of insulin/min into trichloroacetic acid-soluble split products. The purified insulin-degrading enzyme was shown to be homogeneous, as demonstrated by gel chromatography, gel electrophoresis and isoelectric focusing. The isoelectric points was at pH 5.8. The molecular weight of nativ enzyme was estimated by gel chromatography and gel electrophoresis and found to be about 150 000-160 000, consisting of 4 subunits. Degradation products of insulin eluted from a Biogel P 30 column are smaller than the A-chain of the hormone, suggesting the activity of a protease. The enzyme appears to be specific for insulin in that it does not degrade other peptide hormones such as growth hormone, prolactin, or thyroid-stimulating hormone. Furthermore, the enzyme does not inactivate enzymes such as lactate dehydrogenase, aldolase, fructose 1,6-bisphosphatase, hexosephosphate isomerase or hexokinase.
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PMID:Purification to homogeneity of an insulin-degrading enzyme from human erythrocytes. 699 71

A method was developed to measure the activities of enzymes in extracts from single human preimplantation embryos. The method permits the analysis of two enzymes plus appropriate controls in an extract from a single embryo, and was used to investigate the control of energy metabolism during the development of human embryos from the two-cell to the blastocyst stage. Hexokinase (HK), 6-phosphofructokinase (PFK), pyruvate kinase (PK), fructose-1,6-diphosphate aldolase (ALD), glucose phosphate isomerase (GPI), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PDH) and 2-oxoglutarate dehydrogenase (ODH) were all detectable, whereas glycogen phosphorylase (GP) was not. The enzyme activities of ODH, PFK, LDH, PK, GPI and G6PDH, averaged over all stages of development from the two-cell to blastocyst stage (days 2-6 after insemination), were 3.5, 6.6, 15, 69, 73 and 87 times greater than HK, respectively. The activity of ALD was very similar to that of HK. The activities of ALD, GPI, PFK, PK and LDH showed no significant variation with stage of development, although the activity of GPI fell significantly from the four-eight cell to the eight-sixteen cell stage (P < 0.05). HK activity decreased from the two-eight cell to the eight-sixteen cell (P < 0.05), and increased significantly from the eight-sixteen cell to the blastocyst stage (P < 0.01). The overall relationship between hexokinase activity and stage approached significance (P = 0.059, one-way analysis of variance). The activity of G6PDH decreased significantly with development (P < 0.001, one way analysis of variance).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Activity of enzymes of energy metabolism in single human preimplantation embryos. 828 48

Expression of genes encoding enzymes involved in specialized metabolic pathways is assumed to be regulated coordinately to maintain homeostasis in plant cells. We analyzed transcript levels of rice (Oryza sativa L.) genes associated with glycolysis and alcohol fermentation under submergence stress. When each transcript was quantified at several times, two types (I and II) of mRNA accumulation were observed in response to submergence stress. Transcripts of type I genes reached a maximum after 24 h of submergence and were reduced by transfer to aerobic conditions or by partial exposure of shoot tips to air. In a submergence-tolerant rice cultivar, transcript amounts of several type I genes, such as glucose phosphate isomerase, phosphofructokinase, glyceraldehyde phosphate dehydrogenase, and enolase, increased significantly compared to an intolerant cultivar after 24 h of submergence. This suggests that the mRNA accumulation of type I genes increases in response to anaerobic stress. mRNA accumulation of type II genes, such as aldolase and pyruvate kinase, reached a maximum after 10 h of submergence. Following transfer to aerobic conditions, their transcript levels were not so rapidly decreased as were type I genes. These results suggest that the mRNA levels of genes engaged in glycolysis and alcohol fermentation may be regulated differentially under submergence stress.
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PMID:Differential Transcript Levels of Genes Associated with Glycolysis and Alcohol Fermentation in Rice Plants (Oryza sativa L.) under Submergence Stress. 1223 82

Within 72 hours after injection of the LDH agent into normal mice, five (LDH, ICDH, MDH, PHI, and GOT) out of the seven plasma enzymes studied were elevated. This elevation persisted for the duration of the experiment. Alkaline phosphatase and aldolase were not elevated. Plasma from mice bearing tumor SS-70429 and infected with the LDH agent showed 7 times more LDH, 8 times more ICDH, and 4 times more MDH activity than the plasma from mice with the same tumor but uninfected. The plasma aldolase activity from the infected tumor-bearing animal was approximately the same as that from the uninfected tumor-bearing animal. Somewhat similar results, but lower in magnitude, were found with mice bearing mammary carcinoma C(3)HBA. The early rise in plasma enzyme activity (LDH, MDH, ICDH) prior to the actual appearance of the tumor was shown to be due not to the tumor, but to the LDH agent. Uninfected tumor-bearing mice showed a late increase in plasma enzyme activity which appeared to be related to tumor growth. The findings reported above suggest that contamination with the LDH agent may have been responsible for much of the increased plasma enzyme activity previously attributed to the tumor.
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PMID:Multiple enzyme changes in the plasma of normal and tumor-bearing mice following infection with the lactic dehydrogenase agent. 1393 41

A genetic approach was cited for species detection of the ameba genus Naegleria using allozyme electrophoresis to characterize the trophozoite stage of three strains of Naegleria fowleri isolated from patients with primary amebic meningoencephalitis, five thermophilic (45 degrees C) Naegleria spp isolated from natural water sources in the Taling Chan district, and a reference control strain, Naegleria fowleri CDC VO 3081. Isoenzymes of ameba whole-cell extracts were analyzed by vertical polyacrylamide slab gel electrophoresis to determine whether there was any correlation between different strains of the ameba. The results showed that five out of fifteen enzymes; aldehyde oxidase (ALDOX), aldolase (ALD), a-glycerophosphate dehydrogenase (a-GPDH), xanthine dehydrogenase (XDH), and glutamate oxaloacetate transaminase (GOT), were undetectable in the pathogenic strains, while the other enzymes; esterase (EST), fumerase (FUM), glucose-6-phosphate dehydrogenase (G-6-PDH), glucose phosphate isomerase (GPI), isocitate dehydrogenase (IDH), lactate dehydrogenase (LDH), leucine aminopeptidase (LAP), malic enzyme (ME), glucose phosphomutase (GPM), and malate dehydrogenase (MDH), were detected. Naegleria fowleri strains were biochemically the most homogeneous. They showed intraspecific isoenzyme variation that allowed them to be grouped. In contrast, the allozyme patterns (EST 1-7, IDH) of Naegleria spp isolated from the environment showed interspecific isoenzyme variations from the pathogenic Naegleria strain. In conclusion, this study recognized the zymograms of the Naegleria fowleri strains were heterogenically different from the thermophilic 45 degrees C Naegleria spp isolated from the environment.
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PMID:Zymogram patterns of Naegleria spp isolated from natural water sources in Taling Chan district, Bangkok. 1569 Nov 24

Control analysis of the glycolytic flux was carried out in two fast-growth tumor cell types of human and rodent origin (HeLa and AS-30D, respectively). Determination of the maximal velocity (V(max)) of the 10 glycolytic enzymes from hexokinase to lactate dehydrogenase revealed that hexokinase (153-306 times) and phosphofructokinase-1 (PFK-1) (22-56 times) had higher over-expression in rat AS-30D hepatoma cells than in normal freshly isolated rat hepatocytes. Moreover, the steady-state concentrations of the glycolytic metabolites, particularly those of the products of hexokinase and PFK-1, were increased compared with hepatocytes. In HeLa cells, V(max) values and metabolite concentrations for the 10 glycolytic enzyme were also significantly increased, but to a much lesser extent (6-9 times for both hexokinase and PFK-1). Elasticity-based analysis of the glycolytic flux in AS-30D cells showed that the block of enzymes producing Fru(1,6)P2 (i.e. glucose transporter, hexokinase, hexosephosphate isomerase, PFK-1, and the Glc6P branches) exerted most of the flux control (70-75%), whereas the consuming block (from aldolase to lactate dehydrogenase) exhibited the remaining control. The Glc6P-producing block (glucose transporter and hexokinase) also showed high flux control (70%), which indicated low flux control by PFK-1. Kinetic analysis of PFK-1 showed low sensitivity towards its allosteric inhibitors citrate and ATP, at physiological concentrations of the activator Fru(2,6)P2. On the other hand, hexokinase activity was strongly inhibited by high, but physiological, concentrations of Glc6P. Therefore, the enhanced glycolytic flux in fast-growth tumor cells was still controlled by an over-produced, but Glc6P-inhibited hexokinase.
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PMID:Determining and understanding the control of glycolysis in fast-growth tumor cells. Flux control by an over-expressed but strongly product-inhibited hexokinase. 1664 May 61

A fructose diphosphatase-phosphofructokinase substrate cycle has been reconstructed in vitro to provide a system that recycles fructose 6-phosphate and hydrolyses ATP to ADP and P(i). The concerted actions of glucose phosphate isomerase, phosphofructokinase, aldolase and triose phosphate isomerase catalysed the loss of (3)H from [5-(3)H,U-(14)C]glucose 6-phosphate. This was used as the basis of a method for the estimation of the fructose diphosphatase-phosphofructokinase substrate cycle. For the reconstructed cycle, the rate of decrease of the (3)H/(14)C ratio in [5-(3)H,U-(14)C]hexose 6-phosphate was proportional to the rate of fructose 6-phosphate substrate cycling. A detailed theoretical treatment of this relationship is developed, which enables the rate of substrate cycling to be determined in vivo.
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PMID:A model study of the fructose diphosphatase-phosphofructokinase substrate cycle. 1674 19

In order to provide a reference range for normal red blood cell enzyme activities in Thai, we analyzed data from 113 healthy non-anemic Thai people (55 males and 58 females) age 1-42 years, who all had a normal pattern of hemoglobin typing (HbA and HbA2 less than 3.5%). Hematological analysis was performed using an automated cell counter and the hemoglobin studies were carried out by low pressure liquid chromatography. Owing to a high frequency of alpha-thalassemia in Thailand, cases with an MCV < 75 fl were excluded from the study since these cases were likely to be heterozygotes for alpha0-thalassemia. Cases with reticulocytes > 2.5% were excluded from the study since reticulocytes have a higher enzyme activity than mature erythrocytes. Cases with abnormal red blood cell morphology, such as spherocytes and ovalocytes, were also excluded. These criteria were applied to select "normal" controls for our analysis. We assayed eight red blood cell enzyme activities in normal subjects: glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), pyruvate kinase (PK), hexokinase (HK), glucose phosphate isomerase (GPI), phosphofructokinase (PFK), aldolase (ALD) and phosphoglycerate kinase (PGK). The mean normal ranges (+/- SD) for G6PD, 6PGD, PK, HK, GPI, PFK, ALD and PGK were 12.7 (+/-2.2), 10.7 (+/-1.3), 18.5 (+/-4.0), 1.5 (+/-0.4), 80.5 (+/-11.8), 11.8 (+/-2.1), 4.5 (+/-1.6) and 370 (+/-43) IU/gHb, respectively. Age-dependent differences for the reference values for these enzyme activities were summarized. All red blood cell enzyme activities were highest during the early childhood period and slightly lower in the adult period. These values will be of clinically useful for future reference.
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PMID:Development of a comprehensive red blood cell enzymopathy laboratory in Thailand: the study of normal activity in eight erythroenzymes in Thais. 1932 17


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