Unformatted text preview: phosphorylation.
If you want part marks, you need to CLEARLY show enough work so that the marker can follow your
reasoning. Page 14 Question #6 (12 points)
Note: If we run out of time in the last week of classes, we may not finish Metabolism-IV and not all of
this question will be “answerable”.
In Problem Set #6 you looked at a reaction involved in the biosynthesis of bases in nucleotides. This reaction was
catalyzed by aspartate transcarbamoylase (ATCase). Carbonate
2 ATP 2 ADP + Pi + H+ Glutamine + H2O
Glutamate Carbamoyl phosphate
N-carbamoylaspartate UMP UTP CTP Kinetic studies of ATCase activity as a function of aspartate concentration at nearly saturating carbamoyl
phosphate concentrations gives the following results: Page 15 (a) (2 points) Is ATCase an allosteric enzyme? How do you know? (b) (2 points) What kind of effector is CTP? Explain. (c) (3 points) What is the biological significance of CTP’s effect on ATCase? (d) (2 points) What kind of effector is ATP? Explain. (e) (3 points) What is the biological significance of ATP’s effect on ATCase? Page 16...
View Full Document
- Winter '13