Discussion on protein structure formation usually begins with the primary structure or amino acid sequence of the protein, not with amino acid composition. Although we happened to use amino acid composition for investigation of protein structure formability, it resulted in interesting conclusions, as described below.
Structure formability is the same for any protein of the same amino acid composition, that was randomly selected for assembling. This means that every protein synthesized by random peptide bond formation among amino acids in the amino acid composition could be folded into similar but into different structures. Proteins can have the same amino acid composition but different sequences. We call such a specific amino acid composition that is favorable for protein structure formation “protein 0th-order structure”.