第二节 蛋白质生物合成过程 Section 2 Process of protein biosynthesis 生物化学与分子生物学教研室
一、 肽链合成起始 合成起始阶段指mRNA和起始氨基酰一tRNA分别与核 蛋白体结合形成翻译起始复合物的过程。 参与该过程的多种蛋白质因子称为起始因子(initiation factor,IF) 原核的记做IF,真核的记做eF. (）原核翻泽起始复合物的形成 生物化学与分子生物学教研室
月 Ribosome 3 70S ◆ 30S F3 50S Ribosome IF3 70S GTP GDP Pi IF2 : GTP 30S [F3 2山 fMet-tRNAMet GTP 生物化学与分子生物学教研室
IF1 30S IF3 IF1 50S GTP IF2 fMet-tRNAf Met Ribosome 70S 30S IF3 IF1 IF2 GTP IF3 GDP + Pi IF2 GTP IF1 Ribosome 70S IF3
structure ofinitiated complex for prokaryotic translation mRNA small subunit fMet-tRNA Met exit site,E site acceptor site,A site or aminoacyl site large subunit peptide site,Psite or donor site 生物化学与分子生物学教研室
small subunit large subunit fMet-tRNAf Met 5’ 3’ 5’ 3’ mRNA acceptor site, A site or aminoacyl site peptide site, P site or donor site exit site, E site
Initiation of translation for prokaryote ribosome small subunit 16S rRNA UCCU:rpS-1 protein mRNA 53. AGGAPuPuUUUPuPuAUG. 3 Shine-Dalgarno sequence, rpS-1 recognizing and binding sequence SD sequence ribosomal binding sequence 生物化学与分子生物学教研室
Initiation of translation for prokaryote 3’. . 5’ UCCU ribosomal binding sequence mRNA 5’. AGGAPuPuUUUPuPuAUG. 3’ Shine-Dalgarno sequence, SD sequence rpS-1 recognizing and binding sequence 16S rRNA ribosome small subunit rpS-1 protein