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)

Total creatine kinase measurement in serum has remained the best overall marker for detection and monitoring of skeletal muscle diseases, despite that different human tissues exhibit varying distributions of cytoplasmic and mitochondrial isoenzymes of creatine kinase. Acute myocardial infarction aside, increases in total serum creatine kinase, as reflected by the MM isoenzyme, are most commonly caused by injury or diseases to striated muscle. Enzyme markers of skeletal muscle injury that have been previously used (eg, aldolase, enolase, aspartate aminotransferase, and lactate dehydrogenase isoenzyme 5) are not as specific as creatine kinase and have limited clinical utility. However, new enzyme and protein markers are currently being investigated, eg, troponin and carbonic anhydrase III, which are more specific than creatine kinase toward particular tissues. Moreover, measurement of creatine kinase isoforms may provide information about whether muscle turnover is acute or chronic.
Curr Opin Rheumatol 1992 Dec
PMID:Clinical applications of muscle enzymes and proteins. 145 75

Intracellular and serum activities of aldolase (ALS) were biochemically determined in lymphocyte subpopulations from normal subjects and patients with B-chronic lymphocytic leukemia (B-CLL). Aldolase activity was significantly lower in T cells of CLL than in normal T cells (2.9 +/- 1.5 vs. 4.7 +/- 2.1 Sigma Units (SU)/6 x 10(6) cells, p < 0.05). The aldolase activity also was significantly (p < 0.001) lower (3.1 +/- 1.9 SU/6 x 10(6) cells) in CLL B lymphocytes than in normal B lymphocytes (18.1 +/- 6.5 SU/6 x 10(6) cells). Moreover, the serum levels of ALS in all patients with B-CLL were higher than that in normal subjects (8.1 +/- 5.8 vs. 2.2 +/- 0.8 SU/ml, p < 0.02). Our findings demonstrate that T lymphocytes from patients with B-CLL display enzyme activity different from that of normal T cells. This may reflect the abnormal maturity of the residual T cell population in B-CLL.
Int J Hematol 1992 Dec
PMID:Intracellular and serum levels of aldolase activity in B chronic lymphocytic leukemia. 147 33

The pattern of gene expression in fetal hepatocytes transformed in culture with a hepatocarcinogen (FRL cells) is studied with respect to a range of markers which are either developmentally regulated and/or shown to be expressed at high levels in hepatoma cells. The relative abundance of the respective mRNAs is determined and immunocytochemistry is used to detect the respective proteins in cultured cells. When compared with its normal counterpart, FRL cells retain the expression of transferrin, alpha 1-acid glycoprotein, gamma-glutamyltranspeptidase, and tyrosine aminotransferase at near normal levels, while expression of the liver-specific isoenzymes of pyruvate kinase (L form) and aldolase (B form) is reduced. The cell lines are different in that they fail to express albumin, alpha-fetoprotein, thiostatin and alpha 2-macroglobulin, and they express high levels of M2-pyruvate kinase and aldolase A, markers often found in abundance in hepatoma cells. Therefore transformation has resulted in different effects on different genes. Furthermore, it is of interest to find that the cells coexpress both forms of the pyruvate kinase isoenzymes which does not occur in the normal developing hepatocyte. These results indicate that it is possible to use this model to study changes which accompany transformation of fetal rat hepatocytes. The resulting cell lines have a stable phenotype and retain the changes which result from transformation even after extended passaging. This facilitates comparisons between the precursor cell and the tumor cell, both of which can be maintained under controlled conditions which exist in culture.
Cancer Res 1990 Dec 01
PMID:Gene expression in clonally derived cell lines produced by in vitro transformation of rat fetal hepatocytes: isolation of cell lines which retain liver-specific markers. 170 49

In this research on metabolic effects of a high fructose diet, we studied the duration of these effects by measuring the specific activity of 8 enzymes stimulated by such a diet, on days, 0, 3, 6, 9, 15, after the return to a normal diet. In the intestinal mucosa, ketohexokinase, aldolase, triokinase, fructose-diphosphatase, and glucose-6-phosphatase specific activities were still entirely or partially stimulated on the 15th day after return to the standard diet. The stimulation of glucose-6-phosphatase and pyruvate kinase specific activities stopped quickly. In the liver, with the exception of fructose-diphosphatase, the return to basic values was much quicker than in intestine. In 7 enzymes out of 8 it was realized in 9 days or less. When a high fructose diet gives way to a normal one, return to basic values comes so much the quicker as activation has needed longer to appear.
Arch Int Physiol Biochim Biophys 1991 Dec
PMID:Dietary regulation of fructose metabolism in the intestine and in the liver of the rat. Duration of the effects of a high fructose diet after the return to the standard diet. 172 50

The actin filament severing protein, Acanthamoeba actophorin, decreases the viscosity of actin filaments, but increases the stiffness and viscosity of mixtures of actin filaments and the crosslinking protein alpha-actinin. The explanation of this paradox is that in the presence of both the severing protein and crosslinker the actin filaments aggregate into an interlocking meshwork of bundles large enough to be visualized by light microscopy. The size of these bundles depends on the size of the containing vessel. The actin filaments in these bundles are tightly packed in some areas while in others they are more disperse. The bundles form a continuous reticulum that fills the container, since the filaments from a particular bundle may interdigitate with filaments from other bundles at points where they intersect. The same phenomena are seen when rabbit muscle aldolase rather than alpha-actinin is used as the crosslinker. We propose that actophorin promotes bundling by shortening the actin filaments enough to allow them to rotate into positions favorable for lateral interactions with each other via alpha-actinin. The network of bundles is more rigid and less thixotropic than the corresponding network of single actin filaments linked by alpha-actinin. One explanation may be that alpha-actinin (or aldolase) normally in rapid equilibria with actin filaments may become trapped between the filaments increasing the effective concentration of the crosslinker.
J Cell Biol 1991 Dec
PMID:The actin filament severing protein actophorin promotes the formation of rigid bundles of actin filaments crosslinked with alpha-actinin. 175 66

The masses of inositol phosphates have been determined in isolated skeletal muscles from Xenopus laevis (sartorius, tibialis anterior and iliofibularis) and rat (gastrocnemius and soleus) which were quick-frozen in the resting state and at different stages of an isometric (Xenopus) or isotonic (rat) tetanus. The isomeric spectrum of inositol phosphates detected was similar to that in other tissues and cell types. The total sarcoplasmic concentrations of the isomers Ins-(1,4,5,6)P4/Ins(3,4,5,6)P4 (0.2-0.9 microM), Ins(1,3,4,6)P4 (not detectable), Ins(1,3,4,5,6)P5 (about 1 microM) and InsP6 (3.2-4.6 microM) were lower than in other cell types. Variations in these concentrations were due to the muscle type rather than to the donor species. The putative second messenger Ins(1,4,5)P3, as well as its dephosphorylation product Ins(1,4)P2, were present at surprisingly high total myoplasmic resting concentrations, ranging from 1.2 to 2.5 microM and 3.5 to 6.9 microM respectively. Upon tetanic stimulation these two inositol phosphates in particular exhibited significantly increased total sarcoplasmic concentrations, up to 4.2 microM and 11.3 microM respectively, with a time scale of seconds. From the initial rate of increase in the total sarcoplasmic concentrations of Ins(1,4,5)P3 and its rapidly formed metabolic products, a minimal phosphoinositidase C (PIC) activity in tetanically activated Xenopus skeletal muscle of about 1.7-2.6 microM/s can be estimated. This PIC activity observed in vivo seems to be far too low to account for a functional role for Ins(1,4,5)P3 as a chemical transmitter in the fast excitation-contraction coupling (ECC) process in skeletal muscle. The presence of Ins(1,3,4,5)P4 in all muscle types is indicative of a Ca(2+)-activated Ins(1,4,5)P3 3-kinase activity. The rapid transient increases in Ins(1,3,4)P3 and Ins(1,3)P2 in isometrically contracting Xenopus muscles suggest that corresponding Ins(1,3,4,5)P4 phosphatases are operating in skeletal muscle as well. In all muscles investigated except rat soleus, the fructose 1,6-bisphosphate [Fru(1,6)P2] concentration increased substantially during a tetanus, up to about 2 mM. This increase is correlated with a simultaneous decrease in phosphocreatine, whereas the energy charge of the muscles was essentially unaffected by the applied tetani. The time course of the rise in Fru(1,6)P2 was used to model changes in the free concentrations of high-affinity aldolase-binding inositol phosphates during the course of a tetanus. These calculations demonstrate that the free concentration of Ins(1,4,5)P3 and other aldolase-bound inositol phosphates can increase much faster and to a larger extent than the corresponding total concentrations as a result of their competitive displacement from aldolase-binding sites by the rapidly rising concentration of Fru(1,6)P2.
Biochem J 1991 Dec 15
PMID:Masses of inositol phosphates in resting and tetanically stimulated vertebrate skeletal muscles. 176 26

Diethyl pyrocarbonate inactivates Pseudomonas ochraceae 4-hydroxy-4-methyl-2-oxoglutarate aldolase [4-hydroxy-4-methyl-2-oxoglutarate pyruvate-lyase: EC 4.1.3.17] by a simple bimolecular reaction. The inactivation is not reversed by hydroxylamine. The pH curve of inactivation indicates the involvement of a residue with a pK of 8.8. Several lines of evidence show that the inactivation is due to the modification of epsilon-amino groups of lysyl residues. Although histidyl residue is also modified, this is not directly correlated to the inactivation. No cysteinyl, tyrosyl, or tryptophyl residue or alpha-amino group is significantly modified. The modification of three lysyl residues per enzyme subunit results in the complete loss of aldolase activity toward various 4-hydroxy-2-oxo acid substrates, whereas oxaloacetate beta-decarboxylase activity associated with the enzyme is not inhibited by this modification. Statistical analysis suggests that only one of the three lysyl residues is essential for activity. l-4-Carboxy-4-hydroxy-2-oxoadipate, a physiological substrate for the enzyme, strongly protects the enzyme against inactivation. Pi as an activator of the enzyme shows no specific protection. The molecular weight of the enzyme, Km for substrate or Mg2+, and activation constant for Pi are virtually unaltered after modification. These results suggest that the modification occurs at or near the active site and that the essential lysyl residue is involved in interaction with the hydroxyl group but not with the oxal group of the substrate.
J Biochem 1991 Dec
PMID:Chemical modification of Pseudomonas ochraceae 4-hydroxy-4-methyl-2-oxoglutarate aldolase by diethyl pyrocarbonate. 179 88

Subpellicular microtubules isolated from Trypanosoma brucei parasites were fractionated on a phosphocellulose column, and the trypanosomal p52 microtubule-associated protein was eluted along with two other proteins of 41 and 36 kDa. These proteins were found to be the glycosomal enzymes aldolase (41 kDa) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH, 36 kDa) by enzyme activity, antibody cross-reaction, and N-terminal sequencing. These enzymes were coprecipitated with tubulin in the presence of taxol, and aldolase had the capacity to polymerize tubulin and crosslink microtubules. Immunolocalization of anti-aldolase and anti-GAPDH antibodies did not show an interaction between these enzymes and the subpellicular microtubules. The question whether the copurification of aldolase and the subpellicular microtubules could reflect a physiological phenomenon or may be an experimental artifact is discussed.
Exp Cell Res 1990 Dec
PMID:The association of glycosomal enzymes and microtubules: a physiological phenomenon or an experimental artifact? 197 42

We analysed the genetic diversity and environmental correlates of the aldolase A and B genes by means of restriction endonucleases (DNA RFLP analysis), in the four chromosomal species (2n = 52, 54, 58 and 60) of the actively speciating subterranean mole-rats of the Spalax ehrenbergi superspecies in Israel. The results indicated that: (i) both aldolase genes are highly polymorphic; (ii) fragment frequencies and fragment profiles display geographical patterns and significant ecological correlates; (iii) discriminant analysis largely succeeded in separating the four chromosomal species on the basis of variation of aldolase RFLPs.
Heredity (Edinb) 1990 Dec
PMID:Aldolase DNA polymorphism in subterranean mole-rats: genetic differentiation and environmental correlates. 198 68

This work includes a comparative study of aldolase enzyme activity, LDG and its isoenzymes in thoracic duct lymph and blood serum of rabbits in fever reaction dynamics of various duration. Irrespective of its duration the fever was followed by a significant activation of investigated enzymes in the body liquids. However, in many day fever reaction a rise of LDG level in the lymph was more prolonged then that in the blood. The above studies make it possible to assume that the released enzymes in fever reaction are primarily resorbed by lymphatic capillaries and their activity indices in the blood serum are largely evidenced by the transport function of the lymphatic system.
Biull Eksp Biol Med 1990 Dec
PMID:[Activity of several carbohydrate exchange enzymes in the lymph during fever reaction]. 208 55


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