河南师范大学：《生物化学》课程PPT教学课件（英文版）H protein synthesis

H protein synthesis H1 The genetic code H2 Protein synthesis(translation in prokaryotes H3 Translation in eukaryotes 14 Protein targeting H5 Protein glycosylation

• H1 The genetic code • H2 Protein synthesis(translation) in prokaryotes • H3 Translation in eukaryotes • H4 Protein targeting • H5 Protein glycosylation H protein synthesis

Restriction enzymes ● Overview O Restriction enzyme digestion ● Nomenclature ● Gel electrophoresis ● Restriction maps o Restriction fragment length polymorphisms(RFLP)

• Overview • Restriction enzyme digestion • Nomenclature • Gel electrophoresis • Restriction maps • Restriction fragment length polymorphisms(RFLP) Restriction enzymes

H1 The genetic code The genetic code is a triplet code The genetic code is degenerate Universality of the genetic code ° Reading frames Open reading frames

• The genetic code is a triplet code • The genetic code is degenerate • Universality of the genetic code • Reading frames • Open reading frames H1 The genetic code

Triplet code The nucleotide sequence of the mRNA is colinear with the amino acid sequence of the polypeptide in encodes The relationship between them is called the genetic code 5--3N.C terminal

Triplet code • The nucleotide sequence of the mRNA is colinear with the amino acid sequence of the polypeptide in encodes. The relationship between them is called the genetic code • 5’---3’ N terminal-----C terminal

Triplet code The three nucleotides in group called codons 43=64 codons Initiation codon (AUG) stop codon(UAA, UAG, UGA)

Triplet code • The three nucleotides in group called codons • 4 3=64 codons • Initiation codon (AUG) • stop codon ( UAA, UAG,UGA)

Triplet code First position Third position (5 end) Second position (3 end) C Phe Ser Tyr Cys Phe Ser Tyr Leu Ser Stop Stop ucAG Leu Ser Stop Trp Leu P Hi Ar rg Leu Pro His Ar rg C Leu Pro GIn Arg Leu Pro GIn Arg Ile Thr Asn Ser lle Thr A Ser le ys ro Met Thr Lys Arg A Asp Gly ucAGUcAGUcA Va Ala sp Gly G Ala Glu Gly Va Ala Glu y

Triplet code

The genetic code is degenerate 64 codons, but only 20 amino acids, so that, a single amino acid is coded for by several different codons, that is, degenerate Synonyms: different codons specify the same amino acid

The genetic code is degenerate • 64 codons, but only 20 amino acids, so that, a single amino acid is coded for by several different codons, that is, degenerate. • Synonyms:different codons specify the same amino acid

Triplet code Codon and anticodon: a triplet of bases in a specific tRNA molecule. each base is the codon base-pairs with its complementary base in the anticodon Wobble base-pairing

Triplet code • Codon and anticodon: a triplet of bases in a specific tRNA molecule. each base is the codon base –pairs with its complementary base in the anticodon. • Wobble base-pairing

Degeneracy of the genetic code Table 26-4 Degeneracy of the genetic code umino Number of Amino Number of acid codons acid odons Ala Leu Met p Cys GI Glu 622222423 Phe Pro Se 62124641 Thr T His Tyr e

Degeneracy of the genetic code

Wobble rules The Wobble Rules of Codon-Anticodon Pairing 5 Base of Anticodon 3'Base of Codon CAUG GUACU G 04 0C

Wobble rules