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Biosynthesis of protein (translation) PowerPoint Presentation
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Biosynthesis of protein (translation)

Biosynthesis of protein (translation)

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Biosynthesis of protein (translation)

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  1. Biosynthesis of protein (translation)

  2. Materials involved in • the translation • (1) mRNA • a. genetic code • b. the category of genetic • code

  3. c. Triplet code d. Open reading frame (ORF) c. character of the genetic code

  4. * non-spacer,non overlap frame shift & frame shift mutation A DNA 5’-ATG CAT GAC ATT TCG-3’ mRNA 3’-UAC GUA CUG UAA AGC-5’

  5. * degeneracy(synonymous code) & plurality concept significant * wobble

  6. ① ② ③ mRNA密码 5’—G C U—3’ 5’—G C C—3’ 5’—G C A—3’ tRNA反密码3’—C G I—5’ 3’—C G I —5’ 3’—C G I—5’ 3 2 1 U C A I C G U A U G

  7. * Universality (2) tRNA * function *charater

  8. mRNA 5’-AAU CGA-3’ tRNA 3’-UUN GCN-5’ wobble if the first code in anticode of the tRNA is C or A there is no wobble

  9. * Type initiation tRNA concrpt tRNAfmet ( prokaryotes) kind tRNAimet (eukaryotes)

  10. elongation tRNA concept (3) ribosome & polyribome prokaryotes :60s large subunite 40s small subunite eukaryotes: 50s large subunite 30s small subunite

  11. Polyribosome in cytosol biding to the rough endoplasmic reticulum

  12. Soluble factors • initiaotion factors (IF) • elongation factors (EF) • termination factors (RF) • (release factors) • for eukaryotes • eIF, eEF, eRF

  13. (5) Energy & enzymes • 2. the process of synthesis • activation & transfer of • amino acid • * enzyme • aminoacyl-tRNA synthetase

  14. * Catalytic reaction * type type I & type II * Charater two site high specificity

  15. biding site bind & activate E hydrolytic site proofreading

  16. (2) ribosome cycle---- initiation,elongation,termination of the translation A. initiation stage a. requirment

  17. prokaryotes: * dissociated of large & small subunite * The initiation signal in mRNA 5’ end

  18. * Initiation tRNA ( tRNAfmet) * Three types of initiation factors

  19. IF1— help IF3 to bind small subunite,make large & small subunite dissociated IF2---recongnize tRNAfmet , bind to GTP to form triplet then to bind small subunite , possess GTPase activity IF3---bind small subunite, make large & small subunite dissociated

  20. b.form of initiation complex *initiation sequence SD sequence

  21. c.Form of 70s complex mRNA 5’end SD sequence base pair with the 16s rRNA 3’end initiation code of mRNA base pair with anticode of tRNAfmet

  22. 30S起始复合物 + IF3 GTP 50S大亚基 GDP IF1 IF2 70S起始复合物

  23. Elongation of peptide synthesis aminoacyl-tRNA delivery peptide bond formation translocation

  24. aminoacyl-tRNA delivery * protein factors involved * process *character GTPase activity of EF-tu determined pace & fidelity of protein synthesis

  25. EF-tu (have GTPase activity) elongation factor,EF EF-ts