Amino acid activation - Wikipedia Amino acid activation This article has multiple issues. Please help improve it or discuss these issues on the talk page. ( Learn how and when to remove these template messages ) This article is an orphan, as no other articles link to it. Please introduce links to this page from related articles ; try the Find link tool for suggestions. ( December 2009 ) This article does not cite any sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. ( December 2009 ) Amino acid activation refers to the attachment of an amino acid to its Transfer RNA ( tRNA ). Aminoacyl transferase binds Adenosine triphosphate ( ATP ) to amino acid, PP is released. Aminoacyl transferase binds AMP - amino acid to tRNA. The AMP is used in this step. Amino Acid Activation During amino acid activation the amino acids ( aa ) are attached to their corresponding tRNA. The coupling reactions are catalysed by a group of enzymes called aminoacyl - tRNA synthetases ( named after the reaction product aminoacyl - tRNA or aa - tRNA ). The coupling reaction proceeds in two steps : 1. aa + ATP -- > aa - AMP + PP, ( pyrophosphate ) 2. aa - AMP + tRNA -- > aa - tRNA + AMP The amino acid is coupled to the penultimate nucleotide at the 3 ' - end of the tRNA ( the A in the sequence CCA ) via an ester bond ( roll over in illustration ). The formation of the ester bond conserves a considerable part of the energy from the activation reaction. This stored energy provides the majority of the energy needed for peptide bond formation during translation. Each of the 20 amino acids are recognized by its specific aminoacyl - tRNA synthetase. The synthetases are usually composed of one to four protein subunits. The enzymes vary considerably in structure although they all perform the same type of reaction by binding ATP, one specific amino acid and its corresponding tRNA. The specificity of the amino acid activation is as critical for the translational accuracy as the correct matching of the codon with the anticodon. The reason is that the ribosome only sees the anticodon of the tRNA during translation. Thus, the ribosome will not be able to discriminate between tRNAs with the same anticodon but linked to different amino acids. The error frequency of the amino acid activation reaction is approximately 1 in 10 000 despite the small structural differences between some of the amino acids. This biochemistry article is a stub. You can help Wikipedia by expanding it. Retrieved from `` https://en.wikipedia.org/w/index.php?title=Amino_acid_activation&oldid=731663636 '' Categories : Acidic amino acids Biochemistry stubs Hidden categories : Orphaned articles from December 2009 All orphaned articles Articles lacking sources from December 2009 All articles lacking sources All stub articles Talk About Wikipedia Add links This page was last edited on 26 July 2016, at 19 : 11. About Wikipedia

Question: where does the amino acid attach to trna
Answer: the penultimate nucleotide at the 3’-end of the tRNA