Glucose, labeled with ¹⁴C in different carbon atoms, is added to a crude extract of a tissue rich in the enzymes of the pentose phosphate pathway. The most rapid production of ¹⁴CO₂ will occur when the glucose is labeled in:

Question

Quizplus · Accepted Answer

The pentose phosphate pathway involves the oxidative decarboxylation of glucose-6-phosphate, where the C-1 carbon is released as CO2. Therefore, labeling C-1 with 14C will result in the most rapid production of 14CO2.

Glucose, Labeled with 14C in Different Carbon Atoms, Is Added

Glucose, Labeled with ¹⁴C in Different Carbon Atoms, Is Added