I'm desperate and I cannot find the answer to this question....
As the name implies, globular proteiens tend to have a roundish, globular shape. What types of side chains might you expect to find on the amino acid residues that face the outside of a globular protein if it is primarily found in an aqueous environment in the body? What type of side chains might be found facing the inside?
Please HELP ASAP!!
hydrophobic and hydrophilic
To find the answer to your question, we can analyze the characteristics of the amino acid residues in a globular protein that is primarily found in an aqueous environment in the body.
To begin, it is important to note that the aqueous environment of the body consists of water, which is a polar molecule. As a result, water molecules tend to interact with each other through hydrogen bonding and have a strong attraction to other polar molecules. This property is crucial in understanding the distribution of amino acid residues on the outer and inner surfaces of a globular protein.
1. Side chains facing the outside (hydrophilic residues):
Since the outer surface of the globular protein is exposed to the aqueous environment, the amino acid residues facing the outside tend to be hydrophilic (water-loving). These side chains have properties that allow them to interact favorably with water molecules. Examples of hydrophilic side chains include amino acids such as serine, threonine, asparagine, glutamine, lysine, arginine, and histidine. These side chains usually contain polar functional groups, such as hydroxyl (-OH), amine (-NH2), or carbonyl (-CO) groups, which can form hydrogen bonds with water molecules.
2. Side chains facing the inside (hydrophobic residues):
On the other hand, the interior of a globular protein is shielded from the surrounding aqueous environment. This region tends to be hydrophobic (water-fearing) to minimize unfavorable interactions with water. The side chains facing the inside of the protein are usually hydrophobic and lack polar functional groups. Examples of hydrophobic side chains include alanine, isoleucine, leucine, valine, phenylalanine, tryptophan, and methionine. These side chains typically contain nonpolar groups, such as alkyl or aromatic rings, which do not interact well with water.
In summary, the amino acid residues facing the outside of a globular protein found in an aqueous environment are generally hydrophilic, with polar side chains that can interact favorably with water molecules. In contrast, the residues facing the inside tend to be hydrophobic, with nonpolar side chains that minimize interactions with water.