《生物化学》课程PPT教学课件（留学生）Chapter 32 Biosynthesis of Protein

BIOCHEMISTRYANDMOLECULARBIOLOGYChapter 32Biosynthesis of ProteinDepartment of Biochemistry and Molecular Biology,Medicine School

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY Chapter 32 Biosynthesis of Protein

ABIOCHEMISTRYANDMOLECULARBIOLOGYOutline*Overview*Substance for protein synthesis*Biosynthesis of Protein*Post-Translational Modification ofPolypeptideChainsDepartment of Biochemistry and Molecular Biology,Medicine School

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY Outline *Overview *Substance for protein synthesis *Biosynthesis of Protein *Post- Translational Modification of Polypeptide Chains

BIOCHEMISTRYANDMOLECULARBIOLOGY1.overviewGeneexpressionDNATemplatestrandTranscriptionmRNAACCodonTranslationProteinMetProAlaLeuArgfaminoacid chain)AlanineMethionineProlineLeucineArginineeSchool

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY 1. overview

XBIOCHEMISTRYANDMOLECULARBIOLOGY2.Substancefor protein synthesis> mRNA----Template for translation>Ribosome--- Place for protein synthesis>tRNA---Transfer amino acid> The other substanceDepartment of Biochemistry and Molecular Biology,Medicine School

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY 2. Substance for protein synthesis ➢ mRNA-Template for translation ➢Ribosome- Place for protein synthesis ➢tRNA-Transfer amino acid ➢ The other substance

BIOCHEMISTRYANDMOLECULARBIOLOGYmRNA----Template for protein synthesisComponent of genetic codon:>Three of nucleotide in mRNA form a genetic codon,one codon represent one amino acid.>Four kinds of nucleotides comprise 64 codons, 61represent amino acid, 3 of them (UAA、UAG、UGA)are termination codonDepartment of Biochemistry and Molecular Biology,Medicine School

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY Component of genetic codon： ➢Three of nucleotide in mRNA form a genetic codon， one codon represent one amino acid. ➢Four kinds of nucleotides comprise 64 codons，61 represent amino acid，3 of them（UAA、UAG、UGA） are termination codon. mRNA-Template for protein synthesis

Gene expressionDNATemplatestrandTranscriptionCmRNA1CodonTranslationProteinMetProLeuAlaArgTaminoacidchain)MethionineProlineLeucineAlanineArginine

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY

Second letterGUCAUUUUUAUUGUPhenyl-UCUTyrosineCysteineUUCUACCUGCUCCalanineUSerineUCAAUGAUUAUAAStopcodonStop.codonLeucineUCGUAGUUGGUGGStopcodonTryptophanUCAUCGUCUUCCUHistidineCACCCCCCGCCUCProlineLeucineArginineCGACCACUAACAAGlutamineCGGCUGCCGCAGGUAAUAGUAUUACUSerineAsparagineAGCAUCAACIsoleucineCACC-ThreonineAUAACAMethionineAAAAAGALysineArginineACGinitiationAUGAAGAGGGcodonUGAUGUUGCUAsparticGGUGACCGCCGGCGUCacidGValineAlanineGlycineGUAGCAGGAAGAAGlutamicGUGGCGGGGGAGGacid

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY

CAU启HHMetHHGAUStart CodonGGAOGGCUGCCCCUCCOU剪mmnC35

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY

AUGlyPheGluHHHHSerHHAAStopCodonAAN(also UAG and UGA)UCCCCCOLCUU35

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY

mRNA----Template for protein synthesisCharacteristics of codon:>Commaless:The genetic code is nonoverlapping and commaless- that is,the code is read from a fixed starting point as a continuoussequence of bases, taken three at a time.>Degeneracy(Redundancy):(1) Besides Trp （W) and Met （M) ， The other aminoacids have more than one triplet genetic codon.(2) It usually change on the third of nucleotide in thenucleotide -codonDepartment of Biochemistry and Molecular Biology,MedicineSchool

Department of Biochemistry and Molecular Biology, Medicine School BIOCHEMISTRY AND MOLECULAR BIOLOGY Characteristics of codon： ➢Commaless: The genetic code is nonoverlapping and commaless- that is, the code is read from a fixed starting point as a continuous sequence of bases, taken three at a time. ➢Degeneracy(Redundancy): (1) Besides Trp（W) and Met（M），The other amino acids have more than one triplet genetic codon. (2) It usually change on the third of nucleotide in the nucleotide codon mRNA-Template for protein synthesis