transcription-translation-core-1231389105373484 - REVISION-IB2
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The tRNA molecule • tRNA molecules do the final translating • At one end the have a specific amino acid attached by a tRNA activating enzyme These enzymes do the first part of translating • At the other end they have an anticodon which is complementary to the mRNA codons © 2007 Paul Billiet ODWS © St Edward’s University: Dept Chemistry and Biochemistry 3rd position ↓ 2nd position 1st position U C A G U Phe Ser Tyr Cys U Phe Ser Tyr Cys C Leu Ser STOP STOP A Leu Ser STOP Trp G Leu Pro His Arg U Leu Pro His Arg C Leu Pro Gln Arg A Leu Pro Gln Arg G Ile Thr Asn Ser U Ile Thr Asn Ser C Ile Thr Lys Arg A Met Thr Lys Arg G Val Ala Asp Gly U Val Ala Asp Gly C Val Ala Glu Gly A Val Ala Glu Gly G C A G © 2007 Paul Billiet ODWS Acidic Basic Uncharged Polar Non-polar http://learn.genetics.utah.edu/content/begin/dna/firefly/ Translation1 AUGGGAUACACUUUUUGA Ribosome © 2007 Paul Billiet ODWS mRNA Translation 2 met amino acid tRNA UAC anticodon AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 3 gly met CCU UAC AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 4 peptide bond met gly UAC CCU AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 5 tyr met gly AUG UAC CCU AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 6 met gly tyr CCU AUG AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 7 thr met gly tyr UGA CCU AUG AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation 8 phe polypeptide chain met gly tyr thr AAA AUG UGA AUGGGAUACACUUUUUGA © 2007 Paul Billiet ODWS Translation: the sequence • The tRNA molecules with the correct anticodons are lined up with their bases complementary to the mRNA codons • Two tRNA molecules at a time can fit on the ribosome • A peptide bond forms between their amino acids • The first tRNA leaves the ribosome and mRNA move along to accept a new tRNA • The process of translation proceeds in the same direction as replication and transcription (5’ to 3’) © 2007 Paul Billiet ODWS