Peptide Synthesis Lab Report

If I want to target the peptide to different compartments, I would use specific signal sequences or uptake-targeting sequences encoded into my peptide. Signal sequences contain information that will target the peptide to a particular organelle. The information is usually encoded within amino acid sequences of the protein itself, usually within the 20-50 amino acids. Also, each organelle has specific set of receptors that bind only to the specific signal sequences, thus making sure of target specificity. Once the peptide containing the signal sequence has bound to the respective receptor, the peptide is transferred through the lipid bilayer through the translocation channel.
For example in case of
1. Endoplasmic reticulum- ER signal sequence is about 16- to 30- residues in length and they are located on the N-terminal of the protein. Two important components in targeting the protein to the ER membrane include signal-recognition particle (SRP) and its receptor. The SRP binds to the ER signal sequence on the peptide, to the large ribosomal unit and to the SRP receptor.
Mitochondria- The signal sequence targeted to the matrix of mitochondria is located on the N-terminal of the protein. It is an amphipathic helix it is 20-50 residues in length, with Arg and Lys residues on one side and hydrophobic residues on the other end. Unfolded mitochondrial precursor is imported by binding of mitochondrial targeting sequence to an outer receptor in the outer mitochondrial membrane and they are generally designated as Tom proteins. For proteins destined for the mitochondrial matrix, transfer through the outer membrane occurs simultaneously with transfer through an inner membrane channel composed of