試題詳解

15. Thymine nucleotides are not synthesized directly by cells but indirectly from other pyrimidine deoxyribonucleotides. All of the following statements regarding thymine nucleotide synthesis are true EXCEPT:
(A) dUMP is the immediate precursor for dTMP,
(B) The action of dUTPase allows dUTP to serve as a substrate in DNA synthesis,
(C) Thymidylate synthase catalyzes the formation of dTMP from dUMP,
(D) The methyl donor in the reaction of dTMP is N5, N10-methylene-THE,
(E) THF is used as a cofactor.