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Metabolism of nucleic acids. the structure & function. The structure of nucleic acids. 1. summarize. the discovery The function The headway. A. nucleotides. base ( purine、pyrimdine )+ ribose ( deoxyribos N-glycosyl linkage nucleoside+phosphate
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Metabolism of nucleic acids the structure & function
The structure of nucleic acids 1.summarize the discovery The function The headway
base(purine、pyrimdine)+ribose(deoxyribos • N-glycosyl linkage • nucleoside+phosphate • phosphoester linkage • nucleotide • phosphodiester linkage • nucleic acid
The structure of the • nucieic acid
一、the building block molecule of nucleic acid--nucleotide In RNA: AMP、CMP、GMP、TMP In DNA: dAMP、dCMP、dGMP 、dUMP
The physiological function of the nucleotides
二、the linkage ---- phosphodiester bridge 3’terminal 5’terminal Nucleotide residues
三、the primary structure of nucleic acid definition writing method polinucleotide oligonucleotide
四、the structure of DNA 1.the primary structure of DNA * concept * writing method
5’-AATTCGGATCTTAGC-3’ * characteristics specificity in race non specificity in tissues Chargff Law
2.the secondary structure of DNA Watson-Crick double helix structure
3.the force maintaining the double helix stability *hydrogen bond * Stacking force
4. Some difference steric conformation types of DNA double helix
A型 B型 Z型 结晶湿度 75% 92% 高盐溶液结晶 右手 左手 方向 右手 2nm 2.55nm 直径 2.46nm 3.4nm 螺距 表面只有一大沟碱基为嘌啉呤,嘧啶交替, 0.34nm 0.23nm 相邻碱基距离 螺旋一周所含 碱基 12 11 10
5. The tertiary structure of nucleic acid The length of genome DNA 6106Kb DNA supercoiling
Nucleosome ( DNA double helix of containing 200bp ) 140bp DNA double helix histone (H2A1)2,(H2B)2,(H3)2,(H4)2,octamer Core particles 60bp DNAdouble helix fragment+H1histone(linkage region) Core particles a string of beads of nucleosome further fold to form chromosome
五、the structure of RNA 1.summarize • Content • components & linkage • inhomogeneity • steric conformation • function
2. The structure of tRNA * kinds * commonness
(1) The primary structure of tRNA * 5’ PG, 3’ CCA * more rare bases
(2) The secondary structure of tRNA Characteristic structure
*Amino acid arm • * DHU arm DHU ring • * T ψC arm TψC ring • Anticodon arm anticodon ring • extra fork
(3) The tertiary structure of tRNA twisted L
3. The structure of mRNA • Summarize • * characteristic
Prokaryotes --polycistronic Eukaryotes-- monocistronic