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Question
An important difference between a class I and class II aminoacyl-tRNA synthetase is:a. The two classes proceed through different aminoacyl-AMP intermediates.
b. Class I synthetases first attach the amino acid to the 2'-hydroxyl on ribose, whereas class II attach them to the 3'-hydroxyl.
c. Class I synthetases attach amino acids to the 5'-end of the tRNA, whereas class II attach them to the 3'-end.
d. The 5'-end of the tRNA molecule is phosphorylated only for those tRNAs recognized by class I synthetases.
e. None are true.
Answer
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