Aminoacyl-tRNA synthetases have also been called âamino acid activating enzymesâ

a) In what sense do these enzymes âactivateâ amino acids?

b) Aminoacyl-tRNA synthetases must recognize several different substrates. What are they?

RNA structure:

a) In general terms, compare the structure of tRNA and the 16s rRNA.

b) What are the driving forces that lead to these structures? c) Why do these structures tolerate non-canonical base pairs (G:U, A:A, etc.) when such base pairs are not found in DNA?

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Beverley SmithLv2

27 May 2019

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