Glutamic-oxaloacetic enzyme

Other. The most active and the most widely distributed transaminase is the glutamic-oxaloacetic enzyme ... 

Russell, C. D. Cotlove, E. Serum glutamic-oxaloacetic transaminase Evaluation of a coupled-reaction enzyme assay by means of kinetic theory. Clin. Chem. (1971), 17, 1114-1122. 

Increased serum glutamic oxaloacetic transaminase enzyme activity Increased blood pressure increased hemoglobin... 

A few important substances that are routinely analyzed in a clinical laboratory with the aid of an Autoanalyzer are, namely serum-glutamic-oxaloacetic transaminase (SGOT) creatine-phophokinase (CPK) alkaline-phosphatase (AP) belonging to the class of enzymes and a host of biochemical substances, for instance bilirubin, serum albumin, blood urea nitrogen (BUN), uric acid, creatinine, total protein, glucose, cholesterol, besides a few common inorganic ions, such as Cl, Ca2+, K+, Na+. 

The activities of cytoplasmic enzymes, such as aspartase, glutamate, oxaloacetate, malic enzyme, and alcohol dehydrogenase (ADH) decrease at the onset of anaerobiosis, with occasional transient increases on the... 

Alteration of serum enzyme activity has been shown to be a sensitive parameter of tissue injury (20). While the activities of such enzymes as pyruvate kinase, lactate dehydrogenase, glutamate oxaloacetate transaminase, alkaline phosphatase, and creatine phosphokinase in rat serum were significantly altered by the deprivation of dietary vitamin E, the activities of these enzymes were not influenced by smoking exposure under the experimental conditions (Table I). 

There are numerous transminases, each specific to a given substrate pair. Some may be primarily mitochondrial others, cytosolic. For example, glutamate-oxaloacetate transminase (GOT), also called aspartate aminotransferase (AST), is primarily a mitochondrial enzyme. AST is extensively used in the diagnosis of heart and liver disorders (see Chapter 5). The AST reaction is represented by Equation (20.7). 

The child s laboratory tests revealed a normal hematological picture except for a platelet count of 122,000/mm3 (below normal). He had normal liver enzymes except for a serum glutamic oxaloacetic transaminase level of 197... 

The detailed study of enzyme mechanisms requires the use of purified if not homogeneous enzymes. This experiment presents three procedures commonly used in protein purification ammonium sulfate precipitation, heat denaturation, and ion-exchange chromatography. Although the purification procedure outlined in this experiment is useful in the isolation of glutamate-oxaloacetate transaminase (GOT), the same techniques can be modified to aid in the purification of many other proteins of interest. 

In this experiment, you will perform a three-step purification of glutamate-oxaloacetate transaminase from pig heart. With each step in the purification, you will assay different fractions for GOT activity and total protein concentration. These values will then be used to calculate the total activity, specific activity, and percent yield of GOT following each purification step. The goal of the experiment is to achieve 80- to 100-fold purification of the enzyme with >5% yield. The overall effectiveness of the purification procedure will be analyzed by SDS-PAGE on the last day of the experiment. Be sure that you determine three different... 

Figure 3. Schematic representation of five enzyme activity levels in blood serum as a result of various liver diseases. These data (28) do not show the large range in values among individuals. GOT, glutamate-oxaloacetate transaminase GPT, glutamate-pyruvate transaminase GlDH, glutamate dehydrogenase LDH, lactate dehydrogenase P, alkaline phosphatase.

E-11) SCOT (serum glutamate oxaloacetate transaminase), more recently called AST (aspartate aminotransferase), acts at this step. Both names make sense, depending on which way you read the chemical reaction. The enzyme is found in many areas of the body, but Is most useful as a marker of hver or cardiac injury. It leaks out of the damaged cell and increases in the smim after myocardial infarction and liver injury (for instance, hepatitis) and may pros ids clua as to the existence cf theeo coiuhtions. 

Transaminases The transaminases catalyze the reversible transformation of a-ketoacids into amino acids. Most frequently, the 2 transaminases GPT (= glutamic pyruvic transaminase) (or ALT = alamine transaminase) and GOT (= glutamic oxaloacetic transaminase) (or AST = aspartate transaminase) are used for enzyme diagnostics (F. DeRitis et at., 1955 F. Wroblewski et al., 1955). (s. tab. 5.4) While GOT is distributed evenly, the GPT concentration continuously decreases from periportal to pericentral in the acinus. These are considered to be the basic parameters in the diagnosis and follow-up of hepatocellular disease. If the cause of elevated transaminases remains unclear, the indication for liver biopsy is given. (28, 30, 31, 34)... 

PLP is the cofactor for a large number of enzymes used in the metabolism of amino acids and related compounds. Some of these enzymes are listed in Table 9.3. In the aminotransferases, the cofaefor form shifts between PLP and PME In glutamate-oxaloacetate aminotransferase, for example, glutamate reacts with the enzyme bound cofactor and is converted to ot-ketoglutarate. Its amino group remains bound to the cofactor, which is changed to the pyridoxamine phosphate form ... 

The glutamate-oxaloacetate aminotransferase stimulation test involves the reconstitution of PLP with the apoenzyme. The enzyme activity in broken red blood cells is measured with and without PLP added. Addition of PLP would be expected to result in little or no stimulation of enzyme activity if the subject had been consuming a Bg-adequate diet, whereas an increase in enzyme activity with the addition of pure PLP to the enzyme assay mixtures would indicate that the subject had been consuming a Bg-deficient diet. Consumption of a Bg-deficient diet allows continued synthesis of the apoenzyme in the cell, but not conversion of the apoenzyme to the holoenzyme. A marked increase occurring with the addition of PLP could indicate that the subject had been consuming a Bg-deficient diet or that absorption of dietary vitamin Bg was impaired or defective in some way. 

Many important steps in nitrogen metabolism occur in the liver. Liver disease can be severe enough so that urea production may be compromised. Blood urea nitrogen (BUN) levels will decrease, and levels of the toxic compound ammonia will increase. Because the liver is involved in converting bilirubin to the diglucuronide that is excreted in the bile, the levels of bilirubin will increase in the body and jaundice will occur. When liver cells are damaged, enzymes such as aspartate transaminase (AST, also known as GOT, glutamate-oxaloacetate transaminase) will leak into the blood. 

A normochromic anemia may develop rapidly without evidence of GI blood loss, although intestinal bleeding may be contributory. Leukopenia may be reflective of a relative decrease in polymorphonuclear leukocytes. WBC counts may range from 1200 to 20,000 cells/mm . As many as one-third of the patients have elevated levels of the liver enzymes glutamic-oxaloacetic transaminase and alkaline phosphatase in serum. About 80% of patients have positive blood cultures. Bacteremia persists in about a third of cases for several weeks if not treated. Intestinal perforation, intestinal hemorrhage, thrombophlebitis, toxemia with circulatory collapse, encephalopathy, and pneumonia all contribute to a fatality rate of 1 % to 2%. Without treatment, mortality may be 10%. ... 

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