Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Parvalbumin, aldolase and liver alcohol dehydrogenase (ADH), proteins exhibiting long-lived phosphorescence lifetimes at room temperature, were examined for their reactivity with ferricytochrome c (cytochrome c Fe3+) as an external electron acceptor. Illumination of a reaction mixture containing protein and cytochrome c in the absence of oxygen brought about reduction of cytochrome c in relation to the duration of light. The largest portion of reduced cytochrome c was found with a sample containing ADH, where a 50% reduction of cytochrome c was reached after 5 min of illumination with a xenon lamp. Parvalbumin and aldolase were about half as effective under the same conditions. Several lines of evidence support the idea that the reaction of cytochrome c occurred by a long-range electron transfer from the excited triplet state of tryptophan. First, cytochrome c quenches the tryptophan phosphorescence and with parvalbumin, its bimolecular quenching rate constant, kq, was 2.9 x 10(6) M-1 s-1. Second, when the illuminated reaction mixture was supplied with 0.2 mM to 1 mM nitrite, a concentration range of nitrite which quenches the tryptophan phosphorescence but not the fluorescence, the amount of reduced cytochrome c on illumination markedly decreased. Finally, for all illuminated protein samples, the extent of cytochrome c reduction occurred parallel to a decrease in tryptophan content as judged from a decrease in fluorescence intensity and/or a decrease in tryptophan absorption at 280 nm.
 ...
PMID:Electron transfer from excited tryptophan to cytochrome c: mechanism of phosphorescence quenching? 131 64

Solutions of each of three different globular proteins (cytochrome c, chromophorically labeled serum albumin, and chromophorically labeled aldolase), mixed with another unlabeled globular protein or with fibrous actin, were prepared in pH 8.0 Tris-HCl buffer containing 0.15 M NaCl. Each solution was centrifuged at low speed, at 5 degrees C, until unassociated globular protein in solution achieved sedimentation equilibrium. Individual absorbance gradients of both macrosolutes in the mixtures subsequent to centrifugation were obtained via optical scans of the centrifuge tubes at two wavelengths. The gradients of each macrosolute in mixtures of two globular proteins revealed no association of globular proteins under the conditions of these experiments, but perturbation of the gradients of serum albumin, aldolase, and cytochrome c in the presence of F-actin indicated association of all three globular proteins with F-actin. Perturbation of actin gradients in the presence of serum albumin and aldolase suggested partial depolymerization of the F-actin by the globular protein. Analysis of the data with a simple phenomenological model relating free globular protein, bound globular protein, and total actin concentration provided estimates of the respective equilibrium constants for association of serum albumin and aldolase with F-actin, under the conditions of these experiments, of the order of 0.1 microM-1.
 ...
PMID:Interactions between globular proteins and F-actin in isotonic saline solution. 165 57

A method for the preparative high-yield electroelution of proteins from sodium dodecyl sulphate (SDS) polyacrylamide gel strips was established. The method consisted of SDS-polyacrylamide gel electrophoresis, detection of proteins with sodium acetate and electrophoretic elution at 200 V for 3 h by utilizing a horizontal flat-bed gel electrophoresis apparatus. Standard proteins with molecular masses of 14-66 kilodalton (cytochrome c, aldolase, ovalbumin and bovine serum albumin) were recovered with an average yield of 73.6 +/- 2.3%. A membrane-bound protein, rat skeletal muscle Ca(2+)-ATPase (100 kilodalton) was also well recovered (over 60%). This method was applicable to the purification of proteins required for N-terminal amino acid sequencing and to raise antibodies.
 ...
PMID:Preparative high-yield electroelution of proteins after separation by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and its application to analysis of amino acid sequences and to raise antibodies. 166 9

Transferrin, gamma-globulin, fibrinogen, aldolase, albumin, and cytochrome c at concentration of 0.45 muMole/liter were treated with chrysotile and crocidolite fibers. Specific adsorption for each protein and correlations between protein molecular weight and charge density in experimental conditions were evaluated. Chrysotile showed the highest absorption capability, particularly toward albumin and cytochrome c. Affinity for fibers was poorly linked to protein molecular weight; on the contrary, a good correlation with protein charge density was found. The sign of charge on fibers and proteins seemed to play a minor role in adsorption.
 ...
PMID:Adsorption of proteins by chrysotile and crocidolite: role of molecular weight and charge density. 244 62

Measurements of ammonia release provide the first direct evidence that calmodulin becomes extensively deamidated during incubations at 37 degrees C, pH 7.4 or pH 11. A stoichiometry of 0.5 mol of NH3 released/mol of calmodulin is observed after 2 h at pH 11 or after 8-9 days at pH 7.4. These treatments also increase the ability of calmodulin to serve as a substrate for the isoaspartate-specific protein carboxyl methyltransferase from bovine brain. The stoichiometries of methylation are highly correlated with the stoichiometries of ammonia release. Deamidation and increased methyl-accepting capacity also occur in parallel for seven other proteins (aldolase, bovine serum albumin, cytochrome c, lysozyme, ovalbumin, ribonuclease A, and triosephosphate isomerase) upon incubation at pH 11. However, in comparison to calmodulin, these other proteins show very little deamidation and increased methylation capacity following incubation at pH 7.4. Deamidation of calmodulin at pH 7.4 is unaffected by the addition of 10(-7) M Ca2+; however, at 4 X 10(-6) M Ca2+, the rate of deamidation is inhibited by approximately 70%. The Ca2+-protection effect is consistent with the suggestion (B. A. Johnson, N. E. Freitag, and D. W. Aswad, (1985) J. Biol. Chem. 260, 10913-10916) that deamidation occurs preferentially at Asn-60 and/or Asn-97, each of which resides in a distinct Ca2+-binding domain.
 ...
PMID:Deamidation of calmodulin at neutral and alkaline pH: quantitative relationships between ammonia loss and the susceptibility of calmodulin to modification by protein carboxyl methyltransferase. 291 79

The intrinsic fluorescence of lauryl maltoside solubilized bovine heart cytochrome c oxidase has been determined to arise from tryptophan residues of the oxidase complex. The magnitude of the fluorescence is approximately 34% of that from n-acetyltryptophanamide (NATA). This level of fluorescence is consistent with an average heme to tryptophan distance of 30 A. The majority of the fluorescent tryptophan residues are in a hydrophobic environment as indicated by the fluorescence emission maximum at 328 nm and the differing effectiveness of the quenching agents: Cs+, I-, and acrylamide. Cesium was ineffective up to a concentration of 0.7 M, whereas quenching by the other surface quenching agent, iodide, was complex. Below 0.2 M, KI was ineffective whereas between 0.2 and 0.7 M 15% of the tryptophan fluorescence was found to be accessible to iodide. This pattern indicates that protein structural changes were induced by iodide and may be related to the chaotropic character of KI. Acrylamide was moderately effective as a quenching agent of the oxidase fluorescence with a Stern-Volmer constant of 2 M-1 compared with acrylamide quenching of NATA and the water-soluble enzyme aldolase having Stern-Volmer constants of 12 M-1 and 0.3 M-1, respectively. There was no effect of cytochrome c on the tryptophan emission intensity from cytochrome c oxidase under conditions where the two proteins form a tight, 1:1 complex, implying that the tryptophan residues near the cytochrome c binding site are already quenched by energy transfer to the homes of the oxidase. The lauryl maltoside concentration used to solubilize the enzyme did not affect the fluorescence of NATA.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Detection, characterization, and quenching of the intrinsic fluorescence of bovine heart cytochrome c oxidase. 301 Oct 84

The amino acid sequence of fructose-1,6-bisphosphate aldolase from Drosophila melanogaster was determined and was compared with those of five vertebrate aldolases on record. The four identical polypeptide chains of the insect enzyme, acetylated at the N-terminus and three residues shorter than the vertebrate chains, contain 360 amino acid residues. Of these 190 (or 53%) are identical in all six enzymes and in addition 33 positions (or 9%) are occupied by homologous residues. Comparison with the muscle-type isoaldolases from man and rabbit and the liver-type isoaldolases from man, rat, and chicken indicates an average sequence identity of 70 and 63%, respectively. Thus, the insect and the vertebrate muscle aldolases are probably coded by orthologous genes. On this basis an average rate of evolution of 3.0 PAM per 10(8) years is calculated, documenting an evolutional divergence slower than that of cytochrome c (4.2 PAM/10(8) years). The rate is also lower than that of the liver isoform (3.6 PAM/10(8) years). Secondary structure prediction analysis for Drosophila aldolase suggests the occurrence of 11-12 helical segments and 8-9 beta-strands. The conspicuous alternation of these structures in all six aldolases, especially in the C-terminal 200 residues, is consistant with the formation of an alpha beta-barrel supersecondary structure as documented for several other glycolytic enzymes.
 ...
PMID:Fructose-1,6-bisphosphate aldolase from Drosophila melanogaster: primary structure analysis, secondary structure prediction, and comparison with vertebrate aldolases. 314 Jul 28

The Mg,ATP-dependent serine proteinase (Mr = 50 kD; pH optimum 8.0) was isolated and purified 750-fold. The substrate specificity of the enzyme to some protein substrates (catalase, aldolase, uratoxidase, superoxide dismutase, albumin, cytochrome c, insulin) was investigated. The proteinase shows an affinity for proteins whose molecular mass is more than 100 kD. Some quantitative parameters of the enzyme metabolism, e.g., rate constants for synthesis and degradation of serine proteinase and the time of functioning of the de novo synthesized protein, were investigated.
 ...
PMID:[Metabolism and various properties of proteinase controlling catalase metabolism in rat liver mitochondria]. 347 95

Cytoplasmic beta-actin and five glycolytic enzyme cDNAs were isolated from a rat skeletal muscle cDNA library and together with a genomic clone of rat cytochrome c were used as probes to quantitate the respective RNA transcription rates in isolated nuclei run off transcription assays from stationary cells cultured under normal or 2% oxygen. The transcription rates of lactate dehydrogenase, pyruvate kinase, triosephosphate isomerase and aldolase increased by 2-5 fold during the 72 hr exposure to 2% oxygen. There was a small increase in actin RNA transcription while both cytochrome c and glyceraldehyde-3-phosphate dehydrogenase RNA transcription rates decreased. Since previous studies demonstrated an increase in steady state glyceraldehyde-3-phosphate dehydrogenase RNA during low O2 exposure it is concluded that the level of this RNA is regulated post transcriptionally whereas the other four glycolytic enzyme RNAs are regulated at least partially at the level of transcription by oxygen availability. The relative transcriptional rates of the RNAs in this study are related to their cellular RNA and protein concentrations.
 ...
PMID:Regulation of glycolytic enzyme RNA transcriptional rates by oxygen availability in skeletal muscle cells. 369 61

The enzyme pattern of Saccharomyces cerevisiae was followed during batch growth and in continuous culture in a synthetic medium limited for glucose under aerobic conditions. Seven enzymes were measured: succinate-cytochrome c oxidoreductase, malate dehydrogenase, nicotinamide adenine dinucleotide-linked glutamate dehydrogenase, malate synthase, isocitrate lyase, aldolase, and nicotinamide adenine dinucleotide phosphate (NADP(+))-linked glutamate dehydrogenase. During fermentation of glucose and high growth rate (mu) during the first log phase in batch experiments, the first five enzymes (group I) were repressed, and aldolase and NADP(+)-linked glutamate dehydrogenase (group II) were derepressed. During growth on the accumulated ethyl alcohol and lower mu, the group I enzymes were preferentially formed and the other two were repressed. A sequence of derepression of the group I enzymes was found during the shift from glucose to ethyl alcohol metabolism, which can be correlated with a strong increase in the percentage of single (nonbudding) cells in the population. A correlation between the state of cells in the budding cycle and enzyme repression and derepression is suggested. In continuous culture, the enzyme pattern was shown to be related to the growth rate. The group I enzymes were repressed at high growth rates, while the group II enzymes were derepressed. Each enzyme exhibits a different dependence. The enzyme pattern is shown to depend on the rate of substrate consumption as well as on the type of metabolism and to be correlated with the budding cycle. The enzyme pattern is considered to be controlled by changes of intracellular catabolic or metabolic conditions inherent in the division cycle.
 ...
PMID:Enzyme pattern and aerobic growth of Saccharomyces cerevisiae under various degrees of glucose limitation. 438 90


1 2 3 Next >>