A 45-year-old male presents to the Emergency Room with hematemesis and melena, which is actively managed. He has been previously diagnosed with liver cirrhosis. An esophago-gastro- duodenoscopy has been planned and patient has been asked to observe an overnight fast in esophagogastroduodenoscopy preparation of endoscopy. Patient had dinner at 7 pm and endoscopy was performed at 1 pm the next day. At the time of endoscopy, some pathways were generating glucose to maintain serum glucose levels. Which of the following enzymes catalyze the irreversible biochemical reaction of this process?
Correct Answer: Fructose-1,6-bisphosphatase
Description: Answer: c) Fructose-1,6-bisphosphatase* Patient is observing a fast for 18 hours.* During fasting, glycogen storage is usually depleted within 12 hours.* After this point, gluconeogenesis is mainly responsible for maintaining serum glucose levels by converting non-glucose substances to glucose.* It occurs within liver and is opposite of glycolysis with four key irreversible steps.* One of those steps is conversion of Fructose 1,6-bisphosphate to Fructose-6-phosphate.* It is catalyzed by the enzyme, Fructose-1,6-bisphosphatase.* The other irreversible steps are:o The conversion of Pyruvate to Oxaloacetate, catalyzed by Pyruvate carboxylase enzyme and requires biotin.o The conversion of Oxaloacetate to Phosphoenolpyruvate, catalyzed by Phosphoenolpyruvate carboxykinase.o The conversion of Glucose-6-phosphate to Glucose, catalyzed by Glucose 6-phosphatase.
Category:
Biochemistry
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now