The site
of proteins is called what

Ribosomes are the site of protein synthesis, and they convert the coded information in messenger RNA into an actual protein molecule.

I hope this helped! OvO

Your question is not clear whether you are referring to sites of protein synthesis or Protein I-sites so I’ve pasted this paragraph from Wikipedia of the later.

Explanation:

I-sites are short sequence-structure motifs that are mined from the Protein Data Bank (PDB) that correlate strongly with three-dimensional structural elements. These sequence-structure motifs are used for the local structure prediction of proteins. Local structure can be expressed as fragments or as backbone angles. Locations in the protein sequence that have high confidence I-sites predictions may be the initiation sites of folding. I-sites have also been identified as discrete models for folding pathways. I-sites consist of about 250 motifs. Each motif has an amino acid profile, a fragment structure (represented by a "paradigm" fragment chosen from a protein in the PDB) and optionally, a 4-dimensional tensor of pairwise sequence covariance.