In the Picotechnology of Proteins approach, the third letter of the triplet controls the rotation angle of the next amino acid residue relative to the previous one.
As a first approximation, we have 4 variants of the compositional angle Phi, and it is determined according to the 3D genetic code table.
All amino acid residues share a common structural template and differ only in radicals. In this case, by determining the spatial shape of the template, we calculate the spatial structure of the entire protein chain. Thus, we can decipher the protein's letter code into its accurate spatial structure.
Four rotation angles correspond to the assembly of alpha helices (red, right-handed), beta helices (green, left-handed), pi helices (blue, left-handed), and 310 helices (orange, right-handed).
Proline (yellow) is structured as a joint and can form flexible protein segments. Methionine (purple) can also form helices; the methionine helix is right-handed, with the pitch of the methionine helix being approximately 20% larger than that of the alpha helix.
The 2D PicoTech diagram precisely depicts every amino acid residue, every loop, and every segment of the fundamental helices that make up the protein chain, reflecting all the rotation angles using a color chart.
Consequently, the 2D diagram can be unambiguously transformed into a 3D diagram. Therefore, we can compare PicoTech to the descriptive geometry of proteins.
When constructing 3D models, the following are taken into account: deviations of compositional angles, transposition angles, proline joint flexion angles, transition angles between helices, and physicochemical interactions.
