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)

The presence of low molecular weight GTP-binding proteins was investigated in subcellular fractions from skeletal muscle. Skeletal muscle homogenate, transverse tubules, triads, sarcoplasmic reticulum membranes, and cytosol fractions were separated in sodium dodecyl sulfate-gel electrophoresis and blotted onto nitrocellulose. The presence of GTP-binding proteins was explored by incubation of these blots with [alpha-32P] GTP. GTP labeled two polypeptides of Mr = 23,000 and 29,000 in all the fractions examined. Binding of [alpha-32P]GTP was specific and dependent on Mg2+. The 23-kDa polypeptide was labeled to a higher extent with [alpha-32P]GTP than the 29-kDa polypeptide, although both were enriched in transverse tubule fractions. A GTP-binding polypeptide of 40 kDa was also enriched in transverse tubule preparations and identified as Gi alpha by immunostaining with anti-Gi alpha. Using a blot overlay approach and [alpha-32P]GTP-labeled cytosolic components, several polypeptides were identified that interact with the 23- and 29-kDa GTP-binding proteins. Among these components were polypeptides of Mr = 60,000, 47,000, 44,000, 42,000, and 38,000, which were mainly of cytosolic origin but also associated with triads and transverse tubule membranes. The 47-, 44-, 42-, and 38-kDa polypeptides were found to be structurally related to the glycolytic enzymes enolase, 3-phosphoglyceric phosphokinase, aldolase, and glycoeraldehyde-3-phosphate dehydrogenase, respectively. The purified glycolytic enzymes specifically bound the 23- and 29-kDa GTP-binding proteins under both denaturing and nondenaturing conditions. The association of the GTP-binding proteins with these polypeptides was resistant to detergents such as 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS), Triton X-100, and Tween. A 23-kDa GTP-binding protein purified from chromaffin cells bound to a 157-kDa polypeptide in triads and chromaffin cell membranes. The 157-kDa polypeptide was a minor component in these membranes and not related to the subunits of the dihydropyridine receptor. In view of the proposed function of low molecular weight GTP-binding proteins in processes such as membrane communication and secretion coupling, the association of these proteins with transverse tubules and triads in skeletal muscle is discussed in terms of a role in signal transmission.
J Biol Chem 1991 Sep 15
PMID:Identification of low molecular weight GTP-binding proteins and their sites of interaction in subcellular fractions from skeletal muscle. 191 47

When neuroinvasive Escherichia coli K1 cells are grown at temperatures below 20 degrees C, they fail to synthesize the alpha-2,8-linked polysialic acid (polySia) capsule. The objective of this study was to use a genetic and biochemical approach to analyse why capsule expression was defective at cold temperatures. The strategy was to construct E.coli K1-derived mutants with defects in activation and degradation of Sia. The inability to degrade Sia because of a defect in the Sia-specific aldolase permitted accurate quantitation of Sia and CMP-Sia. Strains EV5 and EV90 possessed a defective CMP-Sia synthetase and were unable to activate Sia. These mutants were then used to study how synthesis of Sia, CMP-Sia, and the polySia capsule was affected by growth at 15 degrees C. In contrast to wild type strains, the mutants accumulated Sia in considerable quantities (up to 100 nmol mg protein-1) at 37 degrees C. However, no Sia was detected after growth at 15 degrees C. A temperature upshift experiment showed that the intracellular concentration of Sia increased ca. 3-fold within 5-10 min after shift from 15 to 37 degrees C, even in the presence of inhibitors of protein synthesis or transcription initiation. An in vitro assay for Sia synthase showed that Sia was synthesized at 37 degrees C in cell-free extracts from both 37 and 15 degrees C grown cells, but that no synthesis occurred when the same extracts were assayed at 15 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)
Glycobiology 1990 Sep
PMID:Biosynthesis of the polysialic acid capsule in Escherichia coli K1. Cold inactivation of sialic acid synthase regulates capsule expression below 20 degrees C. 213 86

Eight patients who became ill while taking tryptophan had myalgia, fatigue, rash, fever, edema, alopecia, arthralgias, diminished joint motion, skin tightening, muscle cramping, and distal paresthesias. Three had shortness of breath, and one had pulmonary hypertension. Laboratory abnormalities included peripheral eosinophilia, leukocytosis, thrombocytosis, raised erythrocyte sedimentation rate, and elevated serum levels of aldolase, lactate dehydrogenase, and liver enzymes. Of 4 chest radiographs, 3 were abnormal. Of 5 skin and muscle biopsies, 4 showed sclerosis or mixed inflammatory cell infiltration of the dermis, subcutis, and fascia. Eosinophils were often present, but vasculitis was absent. Muscle inflammation was minimal. We conclude that the "eosinophilia-myalgia syndrome" is related to the ingestion of tryptophan and that abnormalities in the secretion of lymphokines may be important in its pathogenesis.
West J Med 1990 Sep
PMID:Tryptophan-induced eosinophilia-myalgia syndrome. 221 1

Seven cytosolic enzymes with varying half-lives (ornithine decarboxylase, 0.9 h; tyrosine aminotransferase, 3.1 h; tryptophan oxygenase, 3.3 h; serine dehydratase, 10.3 h; glucokinase, 12.7 h; lactate dehydrogenase, 17.0 h; aldolase, 17.4 h) were found to be autophagically sequestered at the same rate (3.5%/h) in isolated rat hepatocytes. Autophagy was measured as the accumulation of enzyme activity in the sedimentable organelles (mostly lysosomes) of electrodisrupted cells in the presence of the proteinase inhibitor leupeptin. Inhibitors of lysosomal fusion processes (vinblastine and asparagine) allowed accumulation of catalytically active enzyme (in prelysosomal vacuoles) even in the absence of proteolytic inhibition, showing that no inactivation step took place before lysosomal proteolysis. The completeness of protection by leupeptin indicates, furthermore, that a lysosomal cysteine proteinase is obligatorily required for the initial proteolytic attack upon autophagocytosed proteins. The experiments suggest that sequestration and degradation of normal cytosolic proteins by the autophagic-lysosomal pathway is a nonselective bulk process, and that nonautophagic mechanisms must be invoked to account for differential enzyme turnover.
J Cell Biol 1990 Sep
PMID:Nonselective autophagy of cytosolic enzymes by isolated rat hepatocytes. 239 70

We have prepared a functional fluorescent analogue of the glycolytic enzyme aldolase (rhodamine [Rh]-aldolase), using the succinimidyl ester of carboxytetramethyl-rhodamine. Fluorescence redistribution after photobleaching measurements of the diffusion coefficient of Rh-aldolase in aqueous solutions gave a value of 4.7 x 10(-7) cm2/S, and no immobile fraction. In the presence of filamentous actin, there was a 4.5-fold reduction in diffusion coefficient, as well as a 36% immobile fraction, demonstrating binding of Rh-aldolase to actin. However, in the presence of a 100-fold molar excess of its substrate, fructose 1,6-diphosphate, both the mobile fraction and diffusion coefficient of Rh-aldolase returned to control levels, indicating competition between substrate binding and actin cross-linking. When Rh-aldolase was microinjected into Swiss 3T3 cells, a relatively uniform intracellular distribution of fluorescence was observed. However, there were significant spatial differences in the in vivo diffusion coefficient and mobile fraction of Rh-aldolase measured with fluorescence redistribution after photobleaching. In the perinuclear region, we measured an apparent cytoplasmic diffusion coefficient of 1.1 x 10(-7) cm2/s with a 23% immobile fraction; while measurements in the cell periphery gave a value of 5.7 x 10(-8) cm2/s, with no immobile fraction. Ratio imaging of Rh-aldolase and FITC-dextran indicated that FITC-dextran was relatively excluded excluded from stress fiber domains. We interpret these data as evidence for the partitioning of aldolase between a soluble fraction in the fluid phase and a fraction associated with the solid phase of cytoplasm. The partitioning of aldolase and other glycolytic enzymes between the fluid and solid phases of cytoplasm could play a fundamental role in the control of glycolysis, the organization of cytoplasm, and cell motility. The concepts and experimental approaches described in this study can be applied to other cellular biochemical processes.
J Cell Biol 1988 Sep
PMID:Aldolase exists in both the fluid and solid phases of cytoplasm. 245 65

A neonate is described whose clinical condition rapidly and irreversibly deteriorated on day two. He developed a profound acidosis, hypoglycaemia and a shock-like syndrome. The infant was centrally cyanosed and had a systolic murmur from a moderately severe pulmonary valve stenosis and a small atrial septal defect. The overwhelming acidosis was inconsistent with the severity of the congenital heart defects and as no infection was found a metabolic cause was sought. Liver tissue obtained at autopsy shortly after death on day four, showed deficiencies of fructose-1, 6-biphosphatase and aldolase.
Acta Paediatr Scand 1989 Sep
PMID:Severe acidosis in a neonate with pulmonary valve stenosis: a possible stress inducer of a fatal syndrome of fructose-1, 6-biphosphatase and aldolase deficiency. 259 90

A 39-year-old female with several past psychiatric hospitalization for schizophrenia was admitted to our hospital because of severe pain and swelling of her legs. A few days before onset, she had often sat down upon her heels in water closet, agitated and talking to herself for many hours. Two days before the admission, she had suffered from severe pain and swelling of her bilateral calf-muscles, and her urine became brownish. On admission, neurological findings revealed delirious state, moderate rigidity of limbs, hyporeflexia of legs, marked swelling and severe spontaneous pain in bilateral legs. She was afebrile with body temperature of 36.4 degrees C. Laboratory data showed marked increase of levels of serum CK to 163,000 U/1, myoglobin to 9,860 ng/ml and aldolase to 42.8 IU/1, and the diagnosis of rhabdomyolysis was made. Although she fell into acute renal failure, the renal function recovered after repeated hemodialysis. Several days after admission, swelling and pain of calf-muscles began to improve, and serum CK, myoglobin and aldolase decreased rapidly. One month later, she was able to walk on her own legs. In the literature, rhabdomyolysis associated with immobile posture caused by schizophrenia is extremely rare, and this is the first case reported in Japan. The relationship between rhabdomyolysis and schizophrenia was discussed.
Rinsho Shinkeigaku 1989 Sep
PMID:[A case of rhabdomyolysis following long time immobile posture caused by schizophrenia]. 259 45

Pyridoxal kinase displays high catalytic activity in the presence of metallothionein. The apoprotein of metallothionein as well as the peptide LYS-CYS-THR-CYS-CYS-ALA exert a strong inhibitory effect upon pyridoxal kinase by sequestering free Zn ions. Several steps intervene in the process of pyridoxal kinase activation, i.e. binding of Zn ions by ATP and interaction of Zn-ATP with the enzyme; but direct interaction between metallothionein and pyridoxal kinase (protein association) could not be detected by emission anisotropy measurements. Since the concentration of free Zn++ in mammalian tissues is lower than 10(-9)M, it is postulated that the concentration of metallothionein regulates the catalytic activity of pyridoxal kinase. The mechanism of reconstitution of the metalloenzyme yeast aldolase in the presence of metallothionein was also investigated.
Biochem Int 1988 Sep
PMID:Modulation of the catalytic activity of pyridoxal kinase by metallothionein. 284 38

Fractionation of rat liver by homogenization and differential centrifugation revealed that only about 83% of the transglutaminase activity in the tissue is in a soluble form, and that the remainder is associated with the particulate fraction. This latter activity remained with the membranes even after they were extensively washed to remove 99% of such soluble enzymes as lactate dehydrogenase and aldolase. Subsequent fractionation of the membranes by isopycnic density gradient centrifugation in sucrose resulted in a single band of transglutaminase activity at a density of 1.194 g/cm3. This activity was coincident with the major band of plasma membranes, which was identified by its content of 5'-nucleotidase, alkaline phosphodiesterase I, alkaline phosphatase and leucine aminopeptidase activities. After treatment with digitonin and fractionation on sucrose gradients, the transglutaminase activity and the plasma membrane marker enzyme activities were found at a new density of 1.210 g/cm3, while the enzyme markers for the other membrane fractions remained unchanged. From these data, we conclude that approximately 17% of the transglutaminase activity in rat liver is specifically associated with the plasma membranes.
Arch Biochem Biophys 1985 Sep
PMID:Subcellular localization of a membrane-associated transglutaminase activity in rat liver. 286 17

The effect of aldolase on the concentration-dependent kinetic behaviour of phosphofructokinase was investigated by means of covalently attached fluorescent probe and by using a kinetic approach. The dimeric form of kinase in equilibrium with the active tetramer interacts with the native aldolase with an apparent dissociation constant of 2.5 microM. Within this heterologous enzyme complex the phosphofructokinase is catalytically active probably because the aldolase binding to nascent kinase dimers might protect them against inactivation.
Biochem Biophys Res Commun 1987 Sep 30
PMID:Aldolase decreases the dissociation-induced inactivation of muscle phosphofructokinase. 295 83


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