Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17174 (aspartate aminotransferase)
 14,872 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The response of guinea pig macrophages to migration inhibitory factor (MIF) is altered by several chemical treatments. Treatment of macrophages with the diazonium salt of sulfanilic acid (5 x 10(-6) to 4 x 10(-4) M) significantly increases the response of these cells to MIF. Treatment with acetic anhydride also augments the response of these cells to MIF. The latter finding suggests that alteration of amino, hydroxyl, or sulfhydryl groups is involved in this phenomenon. Treatment of macrophages with sodium periodate (2 x 10(-5) to 10(-3) M) which is known to oxidize cis-glycols and with hydroxylamine (2 x 10(-5) to 2 x 10(-3) M), which reacts with carbonyl groups also increases response to MIF. The following experiments suggest that the significant alteration occurs at the level of the cell surface. Incubation of macrophages with the diazonium salt of sulfanilic acid at 4 degrees C, at which temperature pinocytosis is largely inhibited, is sufficient to increase the MIF response. The activity of the cytoplasmic enzyme aspartate aminotransferase, which in homogenates is susceptible to inactivation by low concentrations of the diazonium salt of sulfanilic acid, is not decreased when intact macrophages are incubated with high concentrations of the diazonium salt of sulfanilic acid. Cumulatively, these findings suggest that modification of different functional groups on the macrophage surface causes the same physiologic effect.
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PMID:Chemical treatment of macrophages increases their responsiveness to migration inhibitory factor (MIF). 18 95

A method for the purification of two cysteinesulphinate transaminases, A and B (EC 2.6.1), is described. These enzymes catalyse the conversion of cysteinesulphinic acid to beta-sulphinyl pyruvate. The final preparations are homogeneous by polyacrylamide gel electrophoresis, sodium dodecyl sulphate-polyacrylamide gel electrophoresis and isoelectrofocusing. The molecular weight of the subunits is 41 000 for cysteinesulphinate transaminase A and 43 400 for B. Both enzymes are unspecific, as L-asparate, L-glutamate and L-cysteic acid serve as substrates in addition to L-cysteinesulphinic acid. Cysteinesulphinate transaminase A has a Km of 9.8 mM for cysteinesulphinic acid and 0.25 mM for aspartic acid, whereas the B enzyme has a Km of 6.5 mM for cysteinesulphinic acid and 1.4 mM for aspartic acid. The Vmax values of the A and B enzymes are respectively 7.1 and 6.2 mmol h-1 mg-1 protein for aspartic acid and 45 and 9.3 mmol h-1 mg-1 protein for cysteinesulphinic acid. Both enzymes exhibit maximum activity at pH 8.6. A high specific activity is found in optimal conditions for these two transaminases, the pI values being 9.06 and 5.70 for cysteinesulphinate transaminase A and B respectively. These results have been compared with those already obtained for purified aspartate aminotransferase. Similarities in the pathways of taurine and gamma-aminobutyric acid (GABA) metabolism are discussed.
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PMID:Similarities between cysteinesulphinate transaminase and aspartate aminotransferase. 26 60

Minimal liver damage was induced in groups of rats by the administration of three toxicants, viz. carbon tetrachloride, sodium phenobarbitone and orotic acid. Serial blood samples were taken from the animals during the course of the experiment and the plasma levels of a number of enzymes, substrates and metabolites were measured. Liver and kidney samples were also taken at appropriate times after dosing and examined histologically for evidence of drug induced damage. The results of the experiment show that (I) no single test gave unequivocal evidence of liver damage for all three compounds, (II) the conventional liver function tests, alanine transaminase, aspartate transaminase, and alkaline phosphatase, whose plasma activities are usually reported in toxicity studies, were not the most sensitive indicators of the minimal liver cell damage caused by the drugs used in this experiment, (III) knowledge of the intracellular location of the diagnostic enzyme makes it possible to describe, at least in part, the nature of the changes within the liver, (IV) measurement of plasma cholesterol and triglyceride levels can provide information about disruption in lipid metabolism, (V) the times at which blood samples are taken are most important if transient drug effects on the liver are to be detected.
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PMID:Young Scientists Award Lecture 1977: An investigation into the value of some clinical biochemical tests in the detection of minimal changes in liver morphology and function in the rat. 27 87

Transaminase B (branched-chain amino acid aminotransferase, EC 2.6.1.42), the ilvE gene product, was purified to apparent homogeneity from an Escherichia coli K-12 strain which carries the ilvE gene both on the host chromosome and on a plasmid. The oligomeric structure of the enzyme, as determined by analytical ultracentrifugation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was confirmed to be that of a hexamer with a molecular weight of about 182,000 and apparently identical subunits. Cross-linking with dimethylsuberimidate yielded trimers, dimers, and monomers, but essentially no species of higher molecular weight. These results are consistent with a double-trimer arrangement of the subunits in native enzyme. The amino-terminal sequence was found to be: Gly Thr Lys Lys Ala Asp Tyr Ile (Trp) Phe Asn Gly (Thr) (Met) Val. Purified transaminase B catalyzed transamination between alpha-ketoglutarate and l-isoleucine, l-leucine, l-valine, and, to a lesser extent, l-phenylalanine and l-tyrosine, the latter reacting very sluggishly. The enzyme was free of aspartate transaminase and of transaminase C. The apparent K(m) values for the branched-chain alpha-ketoacids were smaller than those for the corresponding amino acids. The lowest K(m) was recorded for dl-alpha-keto-beta-methyl-n-valerate, and the highest was recorded for l-valine. The ratio of the valine- and isoleucine-alpha-ketoglutarate activities did not change significantly during purification, and both activities were quantitatively removed from crude extract by antibody raised against purified transaminase B. These observations argue against the existence of a separate valine-alpha-ketoglutarate transaminase. Anti-E. coli transaminase B antibody cross-reacted with crude extract from Salmonella typhimurium, but not with extract obtained from Pseudomonas aeruginosa.
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PMID:Transaminase B from Escherichia coli: quaternary structure, amino-terminal sequence, substrate specificity, and absence of a separate valine-alpha-ketoglutarate activity. 37 64

In order to verify the influence of sampling time on blood constituents, populations of supposedly healthy subjects were grouped according to age, sex, deviation from their ideal weight, state of fasting or nonfasting, and time of sampling. Each fasting subject in one group underwent two samplings during the course of a morning: the first at 08.00 and the second between 09.00 and 12.00. In the second group, the first was taken at 13.00, and the second between 14.00 and 16.00. Subjects in the second group had eaten a standard meal of 700 calories at 12.00. Differences between the paired samples from a given individual are discussed with respect to the time of sampling for plasma urea, creatinine, proteins, albumin, calcium, sodium, potassium, cholesterol, uric acid, chloride ions, phosphate, bilirubin, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine phosphokinase, alkaline phosphatase, hemoglobin and erythrocyte and leukocyte counts. Variations due to the time of sampling were large for phosphorus, bilirubin, and leukocyte count.
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PMID:The effect of sex, deviation from ideal weight and sampling time on blood constituents in presumably healthy subjects. 43 75

Changes in concentration of a number of blood metabolites in 30 thoroughbred horses were recorded after an 1110 metre race. No significant changes occurred in blood urea or aspartate aminotransferase during the three hours after racing. Plasma sodium, potassium and calcium levels were increased immediately after racing but had returned to normal one hour after racing. Plasma phosphate showed a significant fall in concentration one hour after racing. Creatinine and lactic acid concentrations were elevated ten minutes after racing and although they subsequently decreased, the level of lactic acid was still significant one hour later. Uric acid levels were well above resting levels at ten minutes after racing but rose even more in the subsequent hour. Urinary uric acid levels were also elevated during this time. Three hours after racing some horses still had elevated plasma uric acid levels and all of them showed a significant rise in creatine phosphokinase. The possible physiological basis of these findings is discussed.
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PMID:Changes of blood metabolites in horses after racing, with particular reference to uric acid. 44 60

The effect of danazol in a dose of 600 mg a day was studied in 20 women with moderate or severe endometriosis. The clinical effect was found to be excellent and repeat laparoscopy after about 6 months treatment revealed a marked regression in all patients with only small residual foci of endometriosis in two of them. The side effects were few. The metabolic studies revealed a significant increase in serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), serum potassium, serum albumin and serum creatinine, but a significant decrease in serum gamma glutamyl transpeptidase (GT). Serum sodium showed no alteration. A longitudinal study of basal plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and their responses to 25 microgram gonadotrophic releasing hormone (GnRH) i.v. as well as basal plasma levels of oestradiol, oestrone, progesterone and prolactin was performed. During treatment with danazol (600 mg a day) basal levels of LH, FSH, oestradiol, oestrone and progesterone were low but did not differ from the levels found in the early follicular phase of the menstrual cycle. On the other hand the pituitary response to GnRH was significantly greater for both LH and FSH than observed during the early follicular phase. These conflicting results are discussed. It seems that danazol inhibits the pituitary secretion of biologically active LH and FSH and this action is responsible for the decreased ovarian steroid secretion. Whether the atrophy of the uterine and ectopic endometrium is an effect of the reduced oestradiol levels or is a direct effect of danazol on endometrial oestrogen receptors, or a combination of both modes of action, is not clear.
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PMID:Hormonal, metabolic and clinical effects of danazol in the treatment of endometriosis. 53 48

The results of sending specimens through a computerized pneumatic airtransport system and manually delivering specimens were compared for 15 chemical tests and six hematologic procedures. All specimens were collected from inpatients and outpatients into evacuated glass containers. The specimens traversed a maximum of 829 feet (253 meters) involving 16 bends and eight transfer units at 25 feet/second (7.6 meters/second). Only the activity of lactate dehydrogenase exceeded the precision of the test in pneumatically transported specimens. Ruptured erythrocytes in incompletely filled vacuum tubes were the likely source of the increased lactate dehydrogenase activity. Neither the serum sodium, potassium, chloride, carbon dioxide, total protein, albumin, calcium, glucose, creatinine, total bilirubin, alkaline phosphatase, aspartate transaminase, acid phosphatase, uric acid, leukocyte count, erythrocyte count, hemoglobin, hematocrit, nor the prothrombin time and partial thromboplastin time were affected by pneumatic transport. It is concluded that the pneumatic system tested provides a safe, efficient method of transporting the blood specimens tested.
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PMID:Evaluation of a computer-directed pneumatic-tube system for pneumatic transport of blood specimens. 70 6

The values of a number of biochemical variables have been studied before and after a 50-gram load of glucose orally. Reductions which were statistically significant were found for sodium, potassium, urea, total protein, albumin, calcium, phosphorus, urate, bilirubin, alkaline phosphatase, but not for bicarbonate, creatinine, creatine kinase, lactate dehydrogenase, aspartate aminotransferase, cholesterol, triglyceride or chloride. The magnitude of the changes was generally not great, but could be clinically appreciable. The differences may need to be taken into account in comparing population studies.
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PMID:The effect of 50 grams of glucose orally on a number of biochemical variables. 85 60

Cerebrospinal fluid (CSF) samples were collected from the atlanto-occipital (AO) and lumbosacral (LS) subarachnoid spaces of 24 horses and 21 ponies that had no clinical evidence of neurologic disease. Depth of needle insertion, pressures, refractive index, rapid reagent strip test (protein, glucose, blood, pH) results, cell counts, content of protein, glucose, sodium, potassium, chloride, calcium, phosphorus, urea nitrogen, and cholesterol, and activities of creatine phosphokinase, aspartate transaminase, lactic dehydrogenase, and alkaline phosphatase were determined. The resulting clinical reference values obtained were discussed in light of the published normal values for CSF from horses, other animals, and man. White cell counts in CSF were found to be from 0 to 6/microliters. Values for protein content were distributed between wider limits than previously reported values. The LS-AO difference is proposed as a criterion for clinical evaluation of CSF protein content. Ponies were found to have more protein in their CSF than did the horses, and CSF from the LS site contained more glucose than that from the AO site. The CSF electrolyte composition was similar to that of previous reports. Enzyme activities in equine CSF are reported for the 1st time.
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PMID:Equine cerebrospinal fluid: reference values of normal horses. 91 Oct 95


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