Page 228 - Biochemistry PharmD General

Features of the Genetic Code

• The code is written in the 5’ → 3’ direction.
• Third base is less important in binding to tRNA.
• The first codon establishes the reading frame.

– If reading frame is thrown off by a base or two,
all subsequent codons are out of order.

• 61/64 codons code for amino acids.
• There are three are termination codons:

– UAA, UGA, UAG
• AUG = initiation codon (as well as Met codon).

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