NE224 Lecture Notes - Lecture 16: Phenylalanine, Prokaryotic Small Ribosomal Subunit, Messenger Rna
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The machinery: mrna trna translation factors the ribosome. For a movie of translation see: http://en. wikipedia. org/wiki/translation_(biology) http://www. dnai. org/a/index. html, reading the code putting it together translation (or interactive) The genetic code is in triplets i. e. 3 nucleotides specify 1 aa. The code is degenerate : i. e. 1 aa can be specified by more than 1 codon. The code is widespread, but not completely universal e. g. uga is usually stop, but in mitochondria= trp. Prokaryotes and eukaryotes use the same codons but with different frequencies. The machinery: transfer rna amino acid attachment site. Figure 32-7 the genetic code is read by molecules that recognize a particular codon and carry the corresponding amino acid. Trna acts as an adaptor between the mrna and the protein sequence. The anticodon on the trna binds to the codon on the mrna. Ribosomes are composed of central rrna (16s, 30s, 5s), and many peripheral proteins (see lecturenotes-11)