Question

A tRNA is charged with the amino acid phenylalanine
(a) At what end of tRNA is this amino acid attached?
(b) What is the mRNA codon that codes for phenylalanine?
(c) What is its anticodon?
(d) Name the enzyme responsible for this attachment.

Answer 1

Hint:tRNA is ribonucleic acid which acts as genetic material in some organisms. The term tRNA stands for transfer RNA. The role of tRNA is to form a physical link between the amino acid sequence of proteins and mRNA.

Complete answer: a) tRNA is one of the special kinds of RNA molecules. The function of the tRNA is to form a match of mRNA codon with the amino acid with which it forms codes. Each tRNA consists of a set of three nucleotides called an anticodon. The tRNA has an amino acid acceptor site which is one of the four sites of tRNA. The amino acid is attached to the tRNA at the amino acid acceptor site.
b) The binding of tRNA to the codon takes place inside of the ribosome where they deliver amino acids for addition to the protein chain. Phenylalanine is an amino acid with UUU or UUC mRNA codon that codes for the anticodon AAG of tRNA.
c) One or a few specific mRNA codons binds with the anticodon of a given tRNA. The tRNA molecules also consist of an amino acid specifically, the one encoded by the codons that the tRNA binds. An anticodon is a complementary trinucleotide sequence that codes with the codon on messenger RNA (mRNA).
d) The attachment of anticodon of tRNA with the codon of mRNA which codes for phenylalanine is done with the help of an enzyme called amino acetyltransferase.

Note: There are different types of tRNA found around in a cell. Each tRNA has its own anticodon and matching codon of amino acid. Different synthetase enzymes are used for the attachment of codon with the anticodon of tRNA.