Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
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Disease
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Target Concepts:
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Enzyme
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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)
Extracts of Pseudomonas citronellolis cells grown on glucose or gluconate possessed all the enzymes of the Entner-Doudoroff pathway. Gluconokinase and either or both 6-phosphogluconate dehydratase and KDPG aldolase were induced by growth on these substrates. Glucose and gluconate dehydrogenases and
6-phosphofructokinase
were not detected. Thus catabolism of glucose proceeds via an inducible Entner-Doudoroff pathway. Metabolism of glyceraldehyde 3-phosphate apparently proceeded via glyceraldehyde 3-phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate mutase, enolase and pyruvate kinase. These same enzymes plus triose phosphate isomerase were present in lactate-grown cells indicating that synthesis of triose phosphates from gluconeogenic substrates also occurs via this pathway. Extracts of lactate grown-cells possessed fructose diphosphatase and phosphohexoisomerase but apparently lacked
fructose diphosphate aldolase
thus indicating either the presence of an
aldolase
with unusual properties or requirements or an alternative pathway for the conversion of triose phosphate to fructose disphosphate. Cells contained two species of glyceraldehyde 3-phosphate dehydrogenase, one an NAD-dependent enzyme which predominated when the organism was grown on glycolytic substrates and the other, an NADP-dependent enzyme which predominated when the organism was grown on gluconeogenic substrates.
...
PMID:Enzymatic analysis of the pathways of glucose catabolism and gluconeogenesis in Pseudomonas citronellolis. 23 56
The nucleotide and deduced amino acid sequences of the lacA and lacB genes of the Staphylococcus aureus lactose operon (lacABCDFEG) are presented. The primary translation products are polypeptides of 142 (Mr = 15,425) and 171 (Mr = 18,953) amino acids, respectively. The lacABCD loci were shown to encode enzymes of the tagatose 6-phosphate pathway through both in vitro studies and complementation analysis in Escherichia coli. A serum
aldolase
assay, modified to allow detection of the tagatose 6-phosphate pathway enzymes utilizing galactose 6-phosphate or fructose phosphate analogs as substrate, is described. Expression of both lacA and lacB was required for galactose 6-phosphate isomerase activity. LacC (34 kDa) demonstrated tagatose 6-phosphate kinase activity and was found to share significant homology with LacC from Lactococcus lactis and with both the minor
6-phosphofructokinase
(PfkB) and 1-phosphofructokinase (FruK) from E. coli. Detection of tagatose 1,6-bisphosphate
aldolase
activity was dependent on expression of the 36-kDa protein specified by lacD. The LacD protein is highly homologous with LacD of L. lactis. Thus, the lacABCD genes comprise the tagatose 6-phosphate pathway and are cotranscribed with genes lacFEG, which specify proteins for transport and cleavage of lactose in S. aureus.
...
PMID:Lactose metabolism by Staphylococcus aureus: characterization of lacABCD, the structural genes of the tagatose 6-phosphate pathway. 165 95
Optimal concentrations of the essential components for analyzing the activity of each enzyme associated with glycolysis and gluconeogenesis in rabbit periodontal ligament were examined, and enzyme assay systems for 15 enzymes including 22 reactions were established using triethanolamine buffer. Specific activities of all the enzymes, except for the gluconeogenic reaction of phosphoglycerate kinase, were systematically evaluated using the optimum buffer for each enzyme, since the activity of each enzyme varied depending on the buffer used. For glycolysis, the activity levels of hexokinase and
6-phosphofructokinase
were very low, and consequently these enzyme reactions were inferred to be the rate-limiting steps. For gluconeogenesis, fructose 1,6-bisphosphatase and
aldolase
activities were extremely low, and the activities of glucose 6-phosphatase, phosphoenolpyruvate carboxykinase and pyruvate carboxylase were undetectable. These results suggest that the periodontal ligament may have no gluconeogenesis capability. With a rise in pH, the activities of the key enzymes of glycolysis gradually increased, and a specific "crossover" point was found between the activities of glyceraldehyde-phosphate dehydrogenase and phosphoglyceromutase. In addition, the activity of fructose 1,6-bisphosphatase, one of the key enzymes of gluconeogenesis, was markedly increased with a rise in pH, although pH changes had no effect on
aldolase
activity. Consequently, alkaline pH appeared to result in overall stimulation of glycolysis.
...
PMID:Enzymatic regulation of glycolysis and gluconeogenesis in rabbit periodontal ligament under various physiological pH conditions. 165 53
This study measured axonal transport of
6-phosphofructokinase
(PFK) and
aldolase
activities in the sciatic nerves of rats with short-term streptozotocin-induced diabetes. The diabetic rats showed deficits in anterograde (69% of controls; p less than 0.001) and retrograde (33% of controls; p less than 0.01) accumulations of PFK activity as well as its content per unit length of unconstricted sciatic nerve (86% of controls; p less than 0.05). There were no accumulation deficits in
aldolase
activity in the nerves of the diabetic rats, although the activity per unit length of unconstricted nerve was deficient (81% of controls; p less than 0.05). Treatment of diabetic rats with mixed bovine brain gangliosides (10 mg/kg of body weight/day, i.p.) did not affect the deficit in PFK activity in unconstricted nerve (84% of ganglioside-treated controls; p less than 0.01), but all the other defects in enzyme activities were prevented completely. The diabetic rats also showed a reduction of 7% (p less than 0.01) in sciatic nerve dry weight per unit length, which was prevented by ganglioside treatment. In contrast, the reduced motor nerve conduction velocity, accumulation of polyol pathway metabolites, and depletion of myo-inositol, characteristic of untreated short-term diabetes, were unaffected by ganglioside treatment.
...
PMID:Ganglioside treatment of streptozotocin-diabetic rats prevents defective axonal transport of 6-phosphofructokinase activity. 245 37
A simple procedure has been elaborated to screen for the calmodulin antagonist effect of drugs. A covalently attached fluorescent probe was used to monitor the binding of enzymes known as target enzymes to calmodulin. Moreover, the probe made it possible to recognize a new target enzyme,
aldolase
(
D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase
,
EC 4.1.2.13
), for calmodulin among glycolytic enzymes. The calmodulin antagonist trifluoperazine prevented or eliminated the complex formation between calmodulin and enzymes studied in reconstituted systems; the Ca channel blockers had no effect. The functional consequences of the effect of drugs on calmodulin-phosphofructokinase (
ATP:D-fructose-6-phosphate 1-phosphotransferase
, EC 2.7.1.11) interaction were investigated as well. Whereas trifluoperazine suspended the calmodulin-mediated hysteretic inactivation of phosphofructokinase, Ca channel blockers (verapamil and nifedipine) were ineffective. Fendiline (regarded as a Ca channel blocker) seems to act as a functional calmodulin antagonist. Its binding to calmodulin does not prevent the complex formation of phosphofructokinase and calmodulin, but within this ternary complex phosphofructokinase preserves or recovers its original activity measured in the absence of calmodulin. The possible molecular effect of drugs on a calmodulin-enzyme complex is discussed.
...
PMID:Functional in vitro test of calmodulin antagonism: effect of drugs on interaction between calmodulin and glycolytic enzymes. 283 37
Energy metabolism in proliferating cultured rat thymocytes was compared with that of freshly prepared non-proliferating resting cells. Cultured rat thymocytes enter a proliferative cycle after stimulation by concanavalin A and Lymphocult T (interleukin-2), with maximal rates of DNA synthesis at 60 h. Compared with incubated resting thymocytes, glucose metabolism by incubated proliferating thymocytes was 53-fold increased; 90% of the amount of glucose utilized was converted into lactate, whereas resting cells metabolized only 56% to lactate. However, the latter oxidized 27% of glucose to CO2, as opposed to 1.1% by the proliferating cells. Activities of hexokinase,
6-phosphofructokinase
, pyruvate kinase and
aldolase
in proliferating thymocytes were increased 12-, 17-, 30- and 24-fold respectively, whereas the rate of pyruvate oxidation was enhanced only 3-fold. The relatively low capacity of pyruvate degradation in proliferating thymocytes might be the reason for almost complete conversion of glucose into lactate by these cells. Glutamine utilization by rat thymocytes was 8-fold increased during proliferation. The major end products of glutamine metabolism are glutamate, aspartate, CO2 and ammonia. A complete recovery of glutamine carbon and nitrogen in the products was obtained. The amount of glutamate formed by phosphate-dependent glutaminase which entered the citric acid cycle was enhanced 5-fold in the proliferating cells: 76% was converted into 2-oxoglutarate by aspartate aminotransferase, present in high activity, and the remaining 24% by glutamate dehydrogenase. With resting cells the same percentages were obtained (75 and 25). Maximal activities of glutaminase, glutamate dehydrogenase and aspartate aminotransferase were increased 3-, 12- and 6-fold respectively in proliferating cells; 32% of the glutamate metabolized in the citric acid cycle was recovered in CO2 and 61% in aspartate. In resting cells this proportion was 41% and 59% and in mitogen-stimulated cells 39% and 65% respectively. Addition of glucose (4 mM) or malate (2 mM) strongly decreased the rates of glutamine utilization and glutamate conversion into 2-oxoglutarate by proliferating thymocytes and also affected the pathways of further glutamate metabolism. Addition of 2 mM-pyruvate did not alter the rate of glutamine utilization by proliferating thymocytes, but decreased the rate of metabolism beyond the stage of glutamate significantly. Formation of acetyl-CoA in the presence of pyruvate might explain the relatively enhanced oxidation of glutamate to CO2 (56%) by proliferating thymocytes.
...
PMID:Glutamine and glucose metabolism during thymocyte proliferation. Pathways of glutamine and glutamate metabolism. 286 9
On the basis of the analysis of the data on adsorption of glycolytic enzymes to structural proteins of skeletal muscle and to erythrocyte membranes, the data on enzyme-enzyme interactions and the data on the regulation of activity of glycolytic enzymes by cellular metabolites the structure of glycolytic enzyme complex adsorbed to a biological support has been proposed. The key role in the formation of the multienzyme complex belongs to
6-phosphofructokinase
. The enzyme molecule has two association sites, one of which provides the fixation of
6-phosphofructokinase
on the support and another is saturated by fructose-1,6-bisphosphate
aldolase
. The multienzyme complex fixed on structural proteins of skeletal muscle contains one tetrameric molecule of
6-phosphofructokinase
and at two molecules of other glycolytic enzymes. Hexokinase is not involved in the complex composition. The molecular mass of the multienzyme complex is about 2,6 X 10(6) Da. The formation of the multienzyme complex leads to the compartmentation of the glycolytic process. The problem of integration of physico-chemical mechanisms of enzyme activity regulation (allosteric, dissociative and adsorptive mechanisms) is discussed.
...
PMID:[Supramolecular organization of glycolytic enzymes]. 293 49
On the basis of the analysis of the data on adsorption of glycolytic enzymes to structural proteins of skeletal muscles and to the erythrocyte membranes, the data on enzyme-enzyme interactions and the data on the regulation of activity of glycolytic enzymes by cellular metabolites, the structure of the glycolytic enzymes complex adsorbed to a biological support has been proposed. The key role in the formation of multienzyme complex belongs to
6-phosphofructokinase
. The enzyme molecule has two association sites, one of which provides the fixation of
6-phosphofructokinase
on the support and another is saturated by fructose-1,6-bisphosphate
aldolase
. The multienzyme complex contains one tetrameric molecule of
6-phosphofructokinase
and two molecules of each of other glycolytic enzymes. Hexokinase is not a part of the complex. The molecular mass of the multienzyme complex is about 2.6 X 10(6) daltons. The multienzyme complex has symmetry axis of second order. The formation of the multienzyme complex leads to the compartmentation of glycolytic process. The problem of integration of physico-chemical mechanisms of enzyme activity regulation (allosteric, dissociative and adsorptive mechanisms) is discussed.
...
PMID:Supramolecular organization of glycolytic enzymes. 299 16
Interactions of glucose-6-phosphate isomerase (D-glucose-6-phosphate ketol-isomerase, EC 5.3.1.9),
aldolase
(D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate lyase,
EC 4.1.2.13
), glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12), triose-phosphate isomerase (D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.1.1), phosphoglycerate mutase (D-phosphoglycerate 2,3-phosphomutase, EC 5.4.2.1), phosphoglycerate kinase (ATP:3-phospho-D-glycerate 1-phosphotransferase, EC 2.7.3), enolase (2-phospho-D-glycerate hydro-lyase, EC 4.2.1.11), pyruvate kinase (ATP:Pyruvate O2-phosphotransferase, EC 2.7.1.40) and lactate dehydrogenase [S)-lactate:NAD+ oxidoreductase, EC 1.1.1.27) with F-actin, among the glycolytic enzymes listed above, and with phosphofructokinase (
ATP:D-fructose-6-phosphate 1-phosphotransferase
, EC 2.7.1.11) were studied in the presence of poly(ethylene glycol). Both purified rabbit muscle enzymes and rabbit muscle myogen, a high-speed supernatant fraction containing the glycolytic enzymes, were used to study enzyme-F-actin interactions. Following ultracentrifugation, F-actin and poly(ethylene glycol) tended to increase and KCl to decrease the pelleting of enzymes. In general, the greater part of the pelleting occurred in the presence of both F-actin and poly(ethylene glycol) and the absence of KCl. Enzymes that pelleted more in myogen preparations than as individual purified enzymes in the presence of poly(ethylene glycol) and the absence of F-actin were tested for specific enzyme-enzyme associations, several of which were observed. Such interactions support the view that the internal cell structure is composed of proteins that interact with one another to form the microtrabecular lattice.
...
PMID:Heteromerous interactions among glycolytic enzymes and of glycolytic enzymes with F-actin: effects of poly(ethylene glycol). 333 56
Rat liver cytosolic enzyme preparation catalyses the formation of sedoheptulose 1,7-P2 (60% of total heptulose-P formed) from hexose 6-P and triose 3-P (reverse mode of pentose pathway operation). Smaller amounts of sedoheptulose 1,7-P2 are also formed from ribose 5-P during the non-oxidative synthesis of hexose 6-P (forward pentose pathway operation). The apparent absence of erythrose 4-P in biological systems may be explained by its contribution to carbons 4,5,6 and 7 of sedoheptulose 1,7-P2 as well as its pronounced ability to exist in dimeric form. Apart from the
aldolase
catalyzed formation of sedoheptulose 1,7-P2,
6-phosphofructokinase
also catalyses its formation from sedoheptulose 7-P and fructose 1,6-bisphosphatase catalyses its dephosphorylation. These three enzymes may contribute to the regulation of carbon flux through the near equilibrium reactions of the non-oxidative pentose phosphate pathway in vivo. The phosphotransferase enzyme of the L-type pentose pathway is also able to catalyse the interconversion of sedoheptulose mono and bisphosphates via D-glycero D-ido octulose-P.
...
PMID:The significance of sedoheptulose 1,7-bisphosphate in the metabolism and regulation of the pentose pathway in liver. 408 20
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