Influence of substrate concentration on the activation of transketolase, aspartate aminotransferase, and glutathione reductase by coenzymes.
نویسندگان
چکیده
We investigated the mechanism by which the three most commonly measured enzymes in erythrocytes are activated by their respective coenzymes by determining the catalytic activity concentrations of transketolase (EC 2.2.1.1), aspartate aminotransferase (EC 2.6.1.1), and glutathione reductase (EC 1.6.4.2) in relation to various substrate concentrations. We conclude that the underlying mechanisms by which the enzymes are activated are not the same.
منابع مشابه
Evaluation of methods of coenzyme activation of erythrocyte enzymes for detection of deficiency of vitamins B1, B2, and B6.
We describe optimized, ultraviolet spectrophotometric procedures for determination of erythrocyte transketolase, glutathione reductase, and aspartate aminotransferase activity, and their activation by their respective coenzymes--thiamine pyrophosphate, flavin-adenine dinucleotide, and pyridoxal-5-phosphate--as tests for vitamin B1, B2, and B6 deficiency. With these procedures we have investigat...
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My task at this symposium was to discuss the three B-vitamins, thiamin, riboflavin and pyridoxine and the respective red cell enzymes transketolase (TK; sedoheptulose-7-phosphate: ~-glyceraldehyde-3-phosphate glycolaldehyde transferase; EC 2.2.1.1), glutathione reductase (GR; NADPH,: glutathione oxidoreductase; EC 1.6.4.2) and either aspartate aminotransferase (AST; L-aspartate: 2oxoglutarate a...
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1. Thiamin, riboflavin and pyridoxine status of 'low-income-group' mothers and their newborn infants was assessed by analysing paired samples of maternal and umbilical cord blood for erythrocyte transketolase (EC 2.2.1.1) (ETK), erythrocyte glutathione reductase (EC 1.6.4.2) (EGR), and erythrocyte aspartate aminotransferase (EC 2.6.1.1) (EAA) activities. 2. The vitamin status of the infants was...
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عنوان ژورنال:
- Clinical chemistry
دوره 30 1 شماره
صفحات -
تاریخ انتشار 1984