生物化学与分子生物学09核苷酸代谢duan.pptx

Chapter 8 Metabolism of Nucleotides核苷酸代谢;Section 1 Introduction概 述;Significances of nucleotides核苷酸的生物功用;Nucleoprotein 核蛋白 ;Section 2 Metabolism of Purine Nucleotides嘌呤核苷酸的合成与分解代谢 ;回答以下问题： 1、什么叫从头合成（de novo synthesis）和补救合成（salvage synthesis） 2、嘌呤核苷酸从头合成的原料？氨基酸与嘌呤核苷酸合成的关系？ 3、嘌呤核苷酸从头合成特点？1、嘌呤核苷酸从同合成调节特点？ 4、嘌呤或者嘌呤核苷如何再利用？有何生理意义？ 5、体内dNTP如何生成？ ;There are two pathways leading to nucleotides 核苷酸合成的两条途径;; ;2. Synthesis of IMP IMP的合成;甘氨酰胺核苷酸;5-氨基咪唑-4-羧酸核苷酸;N10-CHOFH4;3. Synthesis of AMP and GMP;4. Formation of NDP and NTP; 嘌呤核苷酸是在磷酸核糖分子上逐步合成的。 高度耗能：IMP的合成需5个ATP，6个高能磷酸键。AMP 或GMP的合成又需1个ATP。 关键步骤：PRPP合成酶，PRPP酰胺转移酶;5. Regulation of de novo synthesis从头合成调节;Regulation of de novo synthesis of purine nucleotides;§ 2.1.2 Salvage pathway 补救合成途径;The course of salvage pathway :; ;Exchange between purines嘌呤核苷酸相互转化;§ 2. 1. 3 Formation of deoxyribonucleotide脱氧核苷酸生成;dNDP + ATP; ; Regulation of ribonucleotide reductase;Summary of purine biosynthesis;§ 2. 1.4 Antimetabolites of purine nucleotides 嘌呤核苷酸抗代谢物;抗代谢物是一些嘌呤、嘧啶、氨基酸、核苷和叶酸的类似物，主要以竞争抑制方式干扰、阻断核苷酸合成代谢或以假乱真掺入核酸，从而阻止核酸以及蛋白质的生物合成。 Antimetabolites of nucleotides are structural analogs of purine, pyrimidine，amino acids and folic acid. They can interfere, inhibit or block synthesis pathway of nucleotides and further block synthesis of RNA, DNA, and proteins. ;1. Purine analogs; ;2. Amino acid analogs;3. Folic acid analogs;;甲酰甘氨酰 胺核苷酸 （FGAR）;§ 2.2 Catabolism of Purine Nucleotides嘌呤核苷酸分解代谢 ;尿酸;; 痛风症的治疗机制;Section 3 Metabolism of Pyrimidine Nucleotides嘧啶核苷酸的合成与分解代谢;§ 3.1 synthesis of pyrimidine nucleotides;1. Element source of pyrimidine base 嘧啶合成的元素来源;2. Synthesis of UMP 先合成UMP;; ;3. Synthesis of CTP;4. Formation of dTMP ;dTMP synthesis at the nucleoside monophosphate level. dTMP在单核苷酸水平上的生成;The enzymes mostly lie in cytosol, but some enzymes exist in mitochondria. The pyrimidine ring is first synthesized, then combines with PRPP. 先合成嘧啶环，再与PRPP连接成核苷酸。 UMP is first synthesized, then UMP is used for synthesizing other p