The lacking enzyme in the infant is glucose-6 phosphatase. When blood glucose is low, glycogen breakdown in liver produce glucose-6-phosphate. G6P release glucose into blood using glucose-6-phosphatase enzyme. This patient is lacking this enzyme so the blood glucose level is low.
2. What is the metabolic reason for elevated levels of blood lactate in this patient? What are the biochemical sources of lactate?
Because of the deficiency of glucose-6 phosphatase enzyme, glucose-6-phosphate cannot be converted into free glucose. Instead, it is hydrolyze into lactic acid which causes the high levels of lactate in urine.
3. What evidence suggests that phosphoglucomutase levels in the patient were normal? …show more content…
The evidence suggests this is assays for liver glucose-6-phosphatase activity showed a 20-fold lower activity per mg liver protein compared to control using either glucose-6-phosphate or glucose-1-phosphate as a substrate.
4. Why were glycogen levels elevated in liver but normal in skeletal muscle? What symptoms, if any, would appear for this patient under exercise?
Because glycogen was stored in liver not muscle. Moreover, only gluconeogenis occur in liver so that the deficiency of phosphoglucomutase enzyme will cause glucose-1-phosphate to accumulate in liver. Less glucose-6-p is formed and less free glucose is formed to be exported from liver. The muscle is not effected.
When the patient exercises, the blood glucose level will drop low. As a result, the liver will want to produce glucose from excess glycogen but it cannot. Therefore, the blood glucose will be low and the lactic acid level will be