Concept explainers
Radiolabeling with 14C-Glutamate Describe the labeling pattern that would result from the introduction into the TCA cycle of glutamate labeled at Cy with 14C.
Interpretation:
The labeling pattern that would result in the introduction of TCA cycle of glutamate
Concept Introduction:
The technique used to track the passage of an isotope or patterns is known as labeling pattern. TCA cycle is abbreviated as tricarboxylic acid. During this cycle, the organism especially aerobic organisms release the energy which will be a stored through the oxidation of acetyl-CoA.
Explanation of Solution
During Mitochondrial Pyruvate Transport, Glutamate maintains the TCA cycle and survival of the cell. The labeling pattern results in the same as the labeling pattern of methyl carbon of acetyl −CoA. Glutamate is converted into a-ketoglutarate and carbon a-ketoglutarate is present in the same position of methyl carbon of acetyl −CoA in the stage of the TCA cycle. In the first cycle, central carbons get labeled. In the second cycle, all the carbons will get a quarter of the label. In the first two cycles, the loss of radioactivity will not be observed. However, in later cycles, 50 % of loss of radioactivity is noticed in the level of each cycle.
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Chapter 19 Solutions
Biochemistry
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