Download Study Guide Nucleotide metabolism 2015

Study Guide for the following Chapters;
Nucleotide Synthesis
1. In the synthesis of IMP, why is the second reaction the first committed
step? What other pathways utilize PRPP?
2. What is the rate-limiting step of purine synthesis?
3. How is the purine synthetic pathway controlled?
4. What are the amino acid sources for the NH2 come from to form AMP &
GMP from IMP?
5. Describe the different mechanisms of amination of IMP to form GMP or
AMP.
6. Explain feed back control in purine synthesis.
7. How does UMP synthesis differ in prokaryotes and eukaryotes?
8. How is prymidine biosynthesis regulated in bacteria and eukaryotic animal
cells?
9. Describe ATCase structure from prokaryotes.
10. How do the concentraions of ATP, CTP and UTP affect the activity of
ATCase?
11. Explain the T-> R transition in ATCase.
12. Describe the evolutionary changes that occur to the proteins pyrimidine
pathway structurally from prokaryotes to eukaryotes?
13. What is the role of CPSII in UMP synthesis in eukaryotic cells?
14. Describe the unusual proton transfer from dihydrooratedh to CoQ that
occurs in eukaryotes.
15. How does the ribosylation of IMP differ from UMP?
16. Discuss the structure of ribonucleotide reductase. Describe the active site
located on the protein? Describe the mechanism of forming the deoxynucleotide.
17. Describe the interaction between the activity site and the specificity site in
ribonucleotide reductase?
18. How do the activity site and the specificity site affect the substratebinding site ribonucleotide reductase?
19. What is the role of thioredoxin and thioredoxin reductase in maintaining the
activity of ribonucleotide reductase? What is the source of reducing power
in this pathway?
20. Discuss the regeneration of N5N10MTHF from the serine-glycine complex
and the methylation of dUMP to form dTMP.
21. Describe the purine nucleotide cycle and its role in skeletal muscle.
22. Describe the role of HGPRT and APRT in recycling purines.
23. How is HGPRT the major deletion mutation that is central to forming a
hybridoma that produces a monoclonal antibody?
24. What is the purine cycle in muscle cells? What is it relationship to the TCA
cycle?