BIOC 302 Lecture Notes - Lecture 23: Stop Codon, Start Codon, Transfer Rna
Document Summary
Protein synthesis trna carry an amino acid and have a triplet binding site. Why do you use triplet binding sites instead of double . Double would only give you 16 opions and there are 20 aas. For triplets there are 64 opions 61 are coding and 3 are stop codons. mrna is read in a non-overlapping fashion. Code degeneracy: except for met and trp, every amino acid is encoded by > 1 triplet (codon) Second posiion = purine polar, pyrimidine non-polar. Third posiion: change from purine to purine will give same aa, change from pyrimidine to pyrimidine will give same aa except aug and uga (a vs g) trna coninued: They fold into a deinite 3-d shape with 4"5 arms: acceptor or amino acid arm, anicodon arm aniparallel, d arm, t c arm, extra arm. The amino acid arm uses the 3"oh to atach the amino acid to it. The d arm some diferent nitrogenous bases in there.
