Aminoactyl-tRNA Synthase is the enzyme responsible for linking the amino acid to the tRNA. A specific enzyme for each amino acid and not for the tRNA.
There are 2 adaptors which translate the genetic code to protein.
Ribosomes are complex machinery that controls protein synthesis and 2 subunits one is large and catalyses the peptide bond formation.
There is 1 small subunit which is small and binds mRNA and tRNA, this contains proteins and RNA. rRNA is central to the catalytic activity and is folded structure which is highly conserved and the protein has less homology and may not be as important.
Ribosomes structures may be free in the cytoplasm or attached to the enoplasmic reticulum. The subunits are in the nucleus in the nucleolus and transported to the cytoplasm.
The 1 large subunit is used to catalyse the formation of the peptide bond and the 1 small units matches the tRNA to the mRNA and moves along the mRNA adding amino acids to growing protein chain.
Ribosomal movement is such that there are 4 binding sites and this the mRNA binding site. The peptidyl-tRNA binding site called the P site, holds tRNA attached to growing end of the peptide.
Aminoacyl-tRNA binding site A which holders the incoming AA and the E site which is the exit site.
**!! REMEMBER TO STAY POSITIVE LIKE A PROTON!!**
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