Final answer:
To design a novel hydrophobic protein, Amino acids with nonpolar side chains would be most essential. These would include amino acids such as alanine, valine, leucine, and others that are hydrophobic and insoluble in water, thus ensuring the protein's hydrophobic characteristic.
Step-by-step explanation:
If you were to design a novel hydrophobic protein, the most essential monomers to incorporate in the molecule would be Amino acids with nonpolar side chains, because these amino acids are insoluble in water and tend to avoid the aqueous environment. Nonpolar amino acids include alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), proline (Pro), methionine (Met), phenylalanine (Phe), and tryptophan (Trp). These amino acids are critical in stabilizing the structure of proteins that are part of cell membranes or function in a nonpolar solvent.
In terms of the specific option from the choices provided, the correct one would be A. Amino acids with nonpolar side chains. This directly relates to the hydrophobic nature required for the protein. Charged or polar side chains would not contribute to the hydrophobic character of a protein and are more commonly found on the surface of membrane proteins in contact with the aqueous environment.
Additionally, molecules that have both polar and nonpolar groups are described as amphipathic (Option B from the reference), and while they contain hydrophobic components, their polar regions make them distinct from purely hydrophobic molecules. On the other hand, polar amino acids such as serine, threonine, and cysteine have hydrophilic side chains, which would not be suitable for creating a hydrophobic protein.