上海交大生物化学课件chapter
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• Deoxyribonucleotides are synthesized by reduction of ribonucleotides(dNDP from NDP)
• Finally, dTMP is formed by methylation甲基化 of dUMP
(UMP→ dUMP → dTMP)
2. Asp (N-1) 3. Gln (N-3, N-9)两次 – FH4 (C-2, C-8)两次 – CO2 (C-6)
.
5
PRPP is the donor of the PR unit of nucleotides (Nt)
• PRPP provides PR portion for the synthesis of Pur and Pyr Nt, just as for that of Trp
CHAPTER 29 BIOSYNTHESIS OF NUCLEOTIDES
➢ Nucleotides play key roles in the following biochemical processes:
1. As activated precursors of DNA and RNA核酸前体
.
6
• PRPP is synthesized from ATP and R-5-P, which is primarily formed by PPP
– PRPP synthetase catalyzes the transfer of the β- γ pyrophosphoryl group of ATP to C-1 of R-5-P
– PRPP has an α-configuration at C-1, the activated carbon atom α构型
.
7
The Pur ring is assembled on PR
• The committed step in the de novo synthesis of Pur Nt is the formation of 5-phosphoribosylamine (5-磷酸核糖胺) from PRPP and Gln
– catalyzed by amido-phosphoribosyl transferase 酰胺磷酸核糖转移酶 – The amide group (酰胺基) from Gln displaces the PPi group attached to C-1
of PRPP – The configuration at C-1 is inverted from α to βin this reaction – The resulting C-N glycosidic bond has βconfiguration that is characteristic of
4. Adenine nucleotides are components of 3 major coenzymes: NAD+, FAD, and CoA辅酶
5. As metabolic regulators, e.g. cAMP and ATP 代谢调节 物
.
2
• Nucleotides are synthesized from simple building blocks (de novo synthesis从头合成) or by the recycling of preformed bases (salvage synthesis节约利用途经)
.
3
.
4百度文库
The purine ring is synthesized from AA, FH4 derivatives, and CO2
• The Pur Ring is assembled de novo from several simple precursors
– 1. Gly (C-4, C-5, N-7)
– Purines (Pur.) and pyrimidines (Pyr.) are built de novo from AA, FH4 derivatives, NH4+ and CO2
– The PR moiety of ribonucleotides comes from PRPP, an activated donor
2. Their derivatives are activated intermediates in many biosyntheses, e.g. UDP-Glc and CDP-DAG and S-A Met 活性中间物
3. ATP is a universal currency of energy in biological systems, GTP powers many movements of macromolecules能量通用形式
naturally occurring Nt β-构型是天然存在的核苷酸中的糖苷键的构型
– This reaction is driven forward by the hydrolysis of PPi
.
8
.
9
.
10
.
11
• PRPP→phosphoribosylamine 磷酸核糖胺
→ glycinamide ribonucleotide 甘氨酰胺核苷酸
• Nucleotide analogs are valuable drugs in the treatment of cancers(P753), viral infections, autoimmune diseases, and genetic disorders such as gout痛风症(P757)
→ formylglycinamide ribonucleotide 甲酰甘氨酰胺核苷酸 → formylglycinamidine ribonucleotide 甲酰甘氨脒核苷 酸→ 5-aminoimidazole ribonucleotide 5-氨基咪唑核苷酸
• Finally, dTMP is formed by methylation甲基化 of dUMP
(UMP→ dUMP → dTMP)
2. Asp (N-1) 3. Gln (N-3, N-9)两次 – FH4 (C-2, C-8)两次 – CO2 (C-6)
.
5
PRPP is the donor of the PR unit of nucleotides (Nt)
• PRPP provides PR portion for the synthesis of Pur and Pyr Nt, just as for that of Trp
CHAPTER 29 BIOSYNTHESIS OF NUCLEOTIDES
➢ Nucleotides play key roles in the following biochemical processes:
1. As activated precursors of DNA and RNA核酸前体
.
6
• PRPP is synthesized from ATP and R-5-P, which is primarily formed by PPP
– PRPP synthetase catalyzes the transfer of the β- γ pyrophosphoryl group of ATP to C-1 of R-5-P
– PRPP has an α-configuration at C-1, the activated carbon atom α构型
.
7
The Pur ring is assembled on PR
• The committed step in the de novo synthesis of Pur Nt is the formation of 5-phosphoribosylamine (5-磷酸核糖胺) from PRPP and Gln
– catalyzed by amido-phosphoribosyl transferase 酰胺磷酸核糖转移酶 – The amide group (酰胺基) from Gln displaces the PPi group attached to C-1
of PRPP – The configuration at C-1 is inverted from α to βin this reaction – The resulting C-N glycosidic bond has βconfiguration that is characteristic of
4. Adenine nucleotides are components of 3 major coenzymes: NAD+, FAD, and CoA辅酶
5. As metabolic regulators, e.g. cAMP and ATP 代谢调节 物
.
2
• Nucleotides are synthesized from simple building blocks (de novo synthesis从头合成) or by the recycling of preformed bases (salvage synthesis节约利用途经)
.
3
.
4百度文库
The purine ring is synthesized from AA, FH4 derivatives, and CO2
• The Pur Ring is assembled de novo from several simple precursors
– 1. Gly (C-4, C-5, N-7)
– Purines (Pur.) and pyrimidines (Pyr.) are built de novo from AA, FH4 derivatives, NH4+ and CO2
– The PR moiety of ribonucleotides comes from PRPP, an activated donor
2. Their derivatives are activated intermediates in many biosyntheses, e.g. UDP-Glc and CDP-DAG and S-A Met 活性中间物
3. ATP is a universal currency of energy in biological systems, GTP powers many movements of macromolecules能量通用形式
naturally occurring Nt β-构型是天然存在的核苷酸中的糖苷键的构型
– This reaction is driven forward by the hydrolysis of PPi
.
8
.
9
.
10
.
11
• PRPP→phosphoribosylamine 磷酸核糖胺
→ glycinamide ribonucleotide 甘氨酰胺核苷酸
• Nucleotide analogs are valuable drugs in the treatment of cancers(P753), viral infections, autoimmune diseases, and genetic disorders such as gout痛风症(P757)
→ formylglycinamide ribonucleotide 甲酰甘氨酰胺核苷酸 → formylglycinamidine ribonucleotide 甲酰甘氨脒核苷 酸→ 5-aminoimidazole ribonucleotide 5-氨基咪唑核苷酸