Question

A protein chain folds into its stable and unique three-dimensional structure, or conformation, by making many noncovalent bonds between different parts of the chain. Such noncovalent bonds are also critical for interactions with other proteins and cellular molecules. From the list provided, choose the class(es) of amino acids that are most important for the interactions detailed below.

A.forming ionic bonds with negatively charged DNA

B.forming hydrogen bonds to aid solubility in water

C.binding to another water-soluble protein

D.localizing an "integral membrane" protein that spans a lipid bilayer

E.tightly packing the hydrophobic interior core of a globular protein

1__acidic, 2__nonpolar, 3__basic, 4__uncharged polar

Answer 1

The answers to the above questions with options A - E are:

A. BASIC class of amino acids are most important for forming ionic bonds with negatively charged DNA.

B. UNCHARGED POLAR class of amino acids are most important for forming hydrogen bonds to aid solubility in water

C. BASIC, UNCHARGED POLAR, ACIDIC, classes of amino acids are most important for binding to another water-soluble protein

D. NON POLAR class of amino acids are most important for localizing an "integral membrane" protein that spans a lipid bilayer

E. NON POLAR class of amino acids are most important for tightly packing the hydrophobic interior core of a globular protein

Step-by-step explanation:

Amino acids are organic molecules that make up proteins, and they are made of a carbon atom, a hydrogen atom, a carboxyl group along with an amino group and a variable group.

Based on the variable group, that gives amino acid specific chemical properties, amino acids can be classified into four categories: acidic, basic, polar, and nonpolar.

Nonpolar amino acids have hydrophobic side chains, making them water repelling because they have little or no polarity in their side chains.

Basic amino acids are positively charged, hence they have side chain with a net positive charge.

Acidic amino acids carry a side chain with a net negative charge.

Uncharged polar amino acids variable groups are soluble in water, and they are electrically neutral.

Answer 2

2, 4, 134, 2

A) forming ionic bonds with negatively charged DNA - non polar family (2)

B) forming hydrogen bonds to aid solubility in water- uncharged polar family (4)

C)binding to another water-soluble protein- is both basic, acidic and uncharged polar.

D) localizing an "integral membrane" protein that spans a lipid bilayer- non polar family.

Step-by-step explanation:

Protein folding is a physical process by which a polypeptide folds into its characteristic and functional three-dimensional (3D) structure from a random coil. Folding occurs even during translation of the polypeptide chain. The most important property of amino acids that affects the folding and the function of the entire protein molecule is their known and predictable interaction with water. (Hydrophobic or hydrophilic)

There are about 5 amino acids that are either acidic or basic, and their R-groups (R means the variable side chain, which is the only chemical group that is different among all twenty amino acids) ionize at various pHs level to produce a chemical structure that has either a positive or negative charge. These types of R-groups are strongly hydrophilic (water loving) and are stabilized when surrounded by water.

Also, there are about 10 nonpolar amino acids with R-groups that are not stable when in contact with water. They are hydrophobic that is, the hate water.

Finally, about 5 amino acids have polar side chains, R-groups which do not ionize or become positively or negatively charged. These R-groups are neither strongly hydrophilic nor hydrophobic they are in-between.