Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.6.1.2 (alanine aminotransferase)
26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The involvement of the first 69 amino acids of eukaryotic elongation factor 1 alpha (EF-1 alpha) from rabbit reticulocyte in GTP and aminoacyl-tRNA binding has been analyzed by a variety of techniques. EF-1 alpha was subjected to limited trypsin digestion, which cleaved predominantly at residues 36 and 69. A digested form of Escherichia coli EF-Tu, similar to the one used for this study, has been characterized by x-ray crystallography and is used as a structural model for EF-1 alpha. This form of EF-1 alpha bound E. coli Phe-tRNAPhe similar to the wild type protein, but lacked activity in phenylalanine polymerization with poly(U)-programmed ribosomes. These results were obtained regardless of whether or not loosely associated N-terminal peptides were removed by gel filtration chromatography. The digested EF-1 alpha also shows reduced GTPase activity, but the activity is stimulated by both ribosomes and aminoacyl-tRNA. Binding of EF-1 alpha to the 80 S ribosome, as determined by association of reductively methylated protein through Sepharose 6B chromatography, is reduced approximately 7-fold for the limited digested form of the protein. Limited digested EF-1 alpha can, however, be photo-cross-linked with GTP and 3'-p-azido-GTP similar to intact EF-1 alpha. Chemical cross-linking with oxidized GTP, fluorosulfonylbenzoyl-GTP, or with trans-diaminedichloroplatinum(II) and GPT, shows a similar modification of both intact and limited digested EF-1 alpha. In order to further localize the modification site with the GTP reagents and assure that modification was not occurring in the first 69 amino acids, intact EF-1 alpha was modified with these same reagents. Limited trypsin digestion of modified protein indicates that none of these reagents cross-links GTP to the first 69 amino acids of EF-1 alpha, which includes the first GTP binding consensus element, GXXXXGK.
...
PMID:Characterization of a limited trypsin digestion form of eukaryotic elongation factor 1 alpha. 199 4

Twenty obese and 20 lean LA/N-cp male rats and 20 male Sprague-Dawley rats were fed a diet containing either 54 percent sucrose or starch for six weeks. After a 14-16 hour fast, rats were killed. Liver and kidney enzyme activities were determined in the LA/N-cp rats while plasma urea and selected amino acids were determined in all rats. Liver glucose-6-phosphatase (G6PASE), fructose-1,6-bisphosphatase (FBPASE), phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), malic enzyme (ME), glucokinase (GK), pyruvate kinase (PK), phosphofructokinase (PFK), glutamic-oxaloacetic-transaminase (GOT), glutamic-pyruvic transaminase (GPT), arginase (ARGASE), arginine-synthase (ARG-SYN) and ornithine transcarbamylase (OTC) levels were significantly affected by phenotype (obese greater than lean). All the above changes in enzyme levels were exaggerated by sucrose-feeding with the exception of PK, PFK, GOT, GPT, ARGASE and ARG-SYN. Kidney cortex G6PASE, PEPCK and ARGASE activities were higher in the obese rats as compared to the lean littermates. Sucrose feeding resulted in higher cortex G6PASE, FBPASE and PEPCK as compared to starch-fed rats. A phenotype effect was noted with plasma glutamate, urea, leucine, isoleucine and valine (obese greater than lean) and a diet effect was seen with aspartate, phenylalanine, leucine and valine (sucrose greater than starch) concentration. Sprague-Dawley rats had higher plasma urea and lower alanine than lean LA/N-cp males. Metabolic obesity in the LA/N-cp rat appears to involve an elevated capacity for pathways of glycolysis, gluconeogensis, lipogenesis and amino acid catabolism in the liver.
...
PMID:Effect of dietary carbohydrate on liver and kidney enzyme activities and plasma amino acids in the LA/N-cp rat. 204 12

The effects of recombinant human interleukin-1 beta (rhIL-1 beta) on various serum constituents were studied following subcutaneous injection (12.5 or 125 micrograms/kg) in female Wistar rats. Protein electrophoresis and the determination of the serum concentrations of carboxypeptidase N (CPN), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, aldolase, total proteins, iron, urea, creatinine, and several amino acids were performed 12, 24, and 72 hr after injection. With both doses of rhIL-1 beta, iron, albumin, CPN, and lysine were significantly decreased whereas alpha 2-globulin, urea, and creatinine were significantly increased 12 hr after administration. Iron and CPN were still low after 24 hr but returned to normal levels after 72 hr. With the higher dose of rhIL-1 beta, only alanine and phenylalanine levels were increased after 12 and 72 hr, taurine after 12 hr, and methionine after 24 hr. There were no biochemical or histological signs of hepatotoxicity. The findings indicate that rhIL-1 beta produces a reversible alteration of various biochemical plasma constituents without any apparent signs of cytotoxicity. Moreover, the decrease in CPN observed may influence the degradation of inflammatory peptides.
...
PMID:Recombinant human interleukin-1 beta decreases serum carboxypeptidase N and modifies serum amino acid concentrations in rats. 278 29

A survey of aminotransferase activities present in a cell-free extract of the anaerobic protozoan, Trichomonas vaginalis was performed. 2-Oxoglutarate, oxaloacetate or phenylpyruvate acted as effective amino acceptors with tyrosine, phenylalanine, tryptophan, leucine, valine, isoleucine, aspartate, alanine, ornithine or lysine. Arginine, serine, glutamine, glycine, beta-alanine and gamma-aminobutyrate were not active as amino donors. With pyruvate as acceptor, significant, yet low, activity was seen only with glutamate, lysine or phenylalanine. Partial purification of enzymes catalysing transamination of leucine, valine, isoleucine, alanine, ornithine and lysine were carried out. A single enzyme catalysed the transamination of ornithine and lysine. The substrate specificity of this enzyme is novel. A separate enzyme catalysed the transamination of all three branched chain amino acids. A third enzyme catalysed the alanine aminotransferase reaction. A fourth enzyme catalysing the transamination both of aromatic amino acids and aspartate has previously been purified [Lowe, P.N. and Rowe, A.F. (1985) Biochem. J. 232, 689-695].
...
PMID:Aminotransferase activities in Trichomonas vaginalis. 309 39

Identification of rat liver mitochondrial asparagine-pyruvate transaminase with phenylalanine-pyruvate transaminase has been done. When a mitochondria extract was subjected to isoelectric focusing, the two enzyme activities were identically focused. This procedure and DEAE-Sepharose chromatography revealed multiple forms of the enzyme, in which the main form was purified. In the various purification steps the two enzyme activities appeared in the same fraction. The enzyme of the final preparation step gave a single band in polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. During the purification, a similar increase of the specific activity and yield were obtained in the two activities. Phenylalanine was found to be a competitive inhibitor of asparagine transaminase. These results suggest the identity of the two enzymes.
...
PMID:Identity of rat liver mitochondrial asparagine-pyruvate transaminase with phenylalanine-pyruvate transaminase. 310 29

(1) The acute effects of ethanol on protein synthesis by liver and skeletal muscle were investigated in young (95-100 g) rats. Rats were injected intraperitoneally with ethanol, 75 mmol/kg body wt; controls were injected with isovolumetric 0.15 M NaCl. After 140 min rates of protein synthesis were measured by injection of a large dose of L[4(3)H]phenylalanine and at 150 min rats were killed. (2) Fractional rates of protein synthesis in control animals were approximately four to five times greater in liver than muscle. Absolute rates were, however, comparable in liver and skeletal muscle. Ethanol reduced the fractional rate of liver protein synthesis by 5-20%; the response for muscle was relatively greater (25-30%). The decrease in the amount of protein synthesized by muscle was also greater than that by liver. (3) After 150 min, plasma gamma-glutamyl transferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase and creatine kinase activities were all decreased by 25-60%. Aspartate aminotransferase activity was increased by 42%, though this was not statistically significant. (4) Increased plasma glucose and triglycerides in ethanol-dosed rats indicated that limitations in substrate supply were not mediating factors in reducing protein synthesis. Ethanol was also able to exert its effects in the presence of elevated insulin levels. A direct effect of ethanol, or its metabolites, on protein synthesis, is therefore implied.
...
PMID:Comparison of the acute effects of ethanol on liver and skeletal muscle protein synthesis in the rat. 339 Feb 39

After surgical placement of end-to-side portacaval shunts (PCS), 4 adult mongrel dogs (11.8 to 18.2 kg) were fed purified diets and monitored for approximately 50 weeks for changes in body weight, neurologic status, and an array of clinically important biochemical variables. Two healthy dogs, fed the same diets and maintained in the same environment, were also observed (controls). Body weights were relatively stable over the period of observation. The branched-chain ratio ([valine] + [leucine] + [isoleucine]/[phenylalanine] + [tyrosine]), an index of the degree of change in plasma amino acid concentrations, was significantly lower in dogs with PCS than in controls. Despite this depression in branched-chain ratio, the principals (dogs with PCS) were essentially free of neurologic symptoms. Statistically significant decreases due to portacaval shunting were seen in the serum concentrations of glucose, calcium, urea nitrogen, creatinine, cholesterol, and albumin. Total protein, globulin, and triglyceride concentrations tended to be lower in the serum of principals than in serum of controls, but the differences were not statistically significant. Statistically significant increases due to portacaval shunting were seen in plasma concentrations of total conjugated bile acids and sulfobromophthalein retention. Concentrations of the following compounds tended to be higher in serum of principals than in serum of controls: phosphorus, chloride, uric acid, total bilirubin, lactate dehydrogenase, aspartate transaminase, alanine transaminase, and alkaline phosphatase. Liver biopsy at 7 months after operation showed mild-to-extensive atrophy of hepatocytes, mild-to-extensive fibrosis, and collapsed portal veins in all principals examined.
...
PMID:Long-term biochemical and physiologic effects of surgically placed portacaval shunts in dogs. 395 18

The effect of a single oral dose of endosulfan (5 mg/kg body weight) on the uptake of certain nutrients and brush-border enzymes has been studied in rat intestine. The uptake of glucose and alanine was elevated but that of leucine was decreased in endosulfan-fed rats. There was no change in the uptake of phenylalanine and lysine in insecticide-fed rats. The activities of brush-border sucrase and alkaline phosphatase were considerably increased while the activity of Na+ K+ ATPase was reduced in endosulfan-exposed animals. The leucine aminopeptidase activity was unaffected in pesticide-treated rats. There was a significant decrease in cellular LDH and GOT activities with no change in GPT activity. Neither was there a considerable increase in the cellular glucose-6-phosphatase activity (P less than 0.01) in the pesticide-fed rats. These results suggest that endosulfan toxicity induces certain functional changes in the intestine.
...
PMID:Effect of a single oral dose of endosulfan on intestinal uptake of nutrients and on brush-border enzymes in rats. 618 May 24

Some experimental and clinical studies were done from the metabolic viewpoint to elucidate the characteristics of myonephropathic-metabolic syndrome. In experimental dogs with their femoral arteries ligated and two third of femoral muscles divided, aldolase and myoglobin showed remarkable increase without significant changes in electrolytes. Slight increase of GPT and GOT was observed. Amino acids showed elevation in urea, taurin, leucin, isoleucin, valine, threonine, 3-methylhistidine, phenylalanine, histidine, lysine, methionine, tyrosine and anserin and decrease in glutamine, alanine, glycine, proline, carnosine, citrullin and arginine. In patients with acute arterial occlusion, potassium, GOT, LDH, CPK, lactate and pyruvate increased moderately and myoglobin showed remarkable increase and aldolase slight increase. Amino acids showed remarkable increase in 3-methylhistidine and beta-amino-isobutyric acid and moderate increase in phenylalanine and arginine. These results revealed that measurement of free amino acid concentration, especially that of methylhistidine as well as myoglobin, pyruvate, lactate and some other enzymes might be of great help to predict the prognosis of patients with acute arterial occlusion of the extremities.
...
PMID:[Metabolic study on acute arterial occlusion of the extremities]. 667 89

Neutral amino acid transport was investigated in Leishmania promastigotes. Proline and alanine transport occur against their concentration gradient although there is a very rapid (40% at 30 min) conversion of proline to alanine. Uptake of these amino acids occurs by a sodium-independent route which is completely eliminated by addition of CCCP or KCN. Km values for proline and alanine are 80 microM and 63 microM with Vmax values of 6.4 and 7.2 nmol/min per mg dry weight, respectively. Countertransport of proline, alanine and phenylalanine was measured by loading the cells with a variety of neutral amino acids and proline analogs, followed by CCCP addition. The effect of aminooxyacetic acid, an inhibitor of alanine aminotransferase (EC 2.6.1.2), on proline and alanine countertransport was also examined. The results obtained are consistent with the presence of at least two systems for neutral amino acid transport in Leishmania promastigotes.
...
PMID:Neutral amino acid transport in Leishmania promastigotes. 684 19


<< Previous 1 2 3 4 5 6 7 Next >>