5 Written Questions
5 Matching Questions
- What does transferase do?
- What is debranching?
- What is the limit dextran?
- What is Uridine Diphosphate?
- What are the properties of the presumptive branch point?
- a Must be at least 4 residues away from other branches. Links are alpha 1,6 glycosidic bond
- b The 4th glucose residue from the branch glucose
- c Transferase transfers the 3 terminal glucose residues from outer branch to the center, main linear branch
- d Uridine diphosphate is a nucleotide composed of uracil, ribose and pyrophosphate
- e When glucose residues are removed to the "limit dextran" which is the 4th glucose residue from the branch glucose
5 Multiple Choice Questions
- PPi+ H2O=> 2Pi
- Utilizes a non branched string of at least 11 glycosyl residues long. Branching enzyme transfers a string of typically 7 residues from non reducing end to presumptive branch point.
- Glucose-1-phosphate +UTP =>UDP-glucose + PPi
- A very large, branched polymer of glucose residues. Most of the glucose residues are linked by alpha 1,4 glycosidic bonds. branches about every 10th residue are linked by alpha 1,6 glycosidic bonds
- Increases the number of terminal glucose residues which are site of action for glycogen phosphorylase and synthase. Branching increases rate of glycogen synthesis and degradation
5 True/False Questions
What is the overall reaction of glycogen phosphorylase activity? → Glucose-1-phosphate +UTP =>UDP-glucose + PPi
What is phosphoglucomutase? → A very large, branched polymer of glucose residues. Most of the glucose residues are linked by alpha 1,4 glycosidic bonds. branches about every 10th residue are linked by alpha 1,6 glycosidic bonds
What enzymes are involved in Glycogen degradation? → Glycogen phosphorylase, Transferase, alpha 1,6 glucosidase, phosphoglucomutase
How is UDP-glucose formed? → UDP-glucose is synthesized from Uridine triphosphate and glucose-1-phosphate via the enzyme UDP-glucose pyrophosphorylase
What is glycogenin? → Glycogenin is both an enzyme and its substrate consisting of two 37 kD subunits. Each subunit catalyzes addition of a glycosyl unit from UDP glucose to Tyr 194 of other subunit. Subsequently, 7 more glycosyl units are added so that 8 glycosyl units are attached to Tyr 194 for each subunit