问题 单项选择题

TMP的分解代谢产物是

A.尿酸
B.β-丙氨酸
C.β-氨基异丁酸
D.胺

答案

参考答案:C

解析:①嘧啶核苷酸的分解代谢途径为:
胞嘧啶C→尿嘧啶U→…→β-脲基丙酸→β-丙氨酸+CO2+NH3
胸腺嘧啶T→→→→→…→β-脲基异丁酸→p-氨基异丁酸+CO2+NH3
因此,CMP的分解代谢产物是β-丙氨酸,TMP的分解代谢产物是β-氨基异丁酸。尿酸是嘌呤核苷酸的分解代谢产物。

解答题
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