Question

Primary structure of polypeptide is stabilised or secondary structure of polypeptide is maintained by
a. Hydrogen bonds
b. Disulfide bonds
c. Ionic bonds
d. Hydrophobic interactions

Answer 1

Hint: A polypeptide contains partial intermolecular holding cooperation between a solitary pair on an electron-rich particle, especially the second-line components nitrogen, oxygen, or fluorine, and the antibonding sub-atomic orbital of a bond between a proton in one particle and an electronegative molecule in the other.

Complete answer:
The secondary structure of the primary polypeptide is maintained by the hydrogen bond. The Alpha helix structure of the protein is a type of optional structure of the protein. It is framed because of the development of hydrogen connections between spine amide and carbonyl gatherings.

The hydrogen bonds are framed between $N - H$ gathering of one amino build-up with a $C = O$ group of fourth amino corrosive from the amino corrosive bearing $N - H$ gathering. Each turn of the alpha helix contains 3.6 amino corrosive build-ups. $\beta $-creased optional protein structure is framed by the equal or against equal polypeptide steel together by H-bonds. It is balanced out by the hydrogen bonds framed between $N - H$ and $C = O$ of the neighboring polypeptide chains.

Auxiliary structure alludes to ordinary, repeating courses of action in space of neighboring amino corrosive deposits in a polypeptide chain. It is kept up by hydrogen connections between amide hydrogens and carbonyl oxygen of the peptide spine.

In this structure, the polypeptide spine is firmly twisted around the long pivot of the atom, and R gatherings of the amino corrosive build-ups project outward from the helical spine. The rehashing unit is a solitary turn of a helix, which reaches out about 0.54nm with the pivot, and the quantity of amino corrosive build-ups required for one complete turn is 3.6.

Hence, the correct answer is option (A).

Additional information:
Disulfide bond arrangement happens in the endoplasmic reticulum by oxidation. Hence disulfide bonds are generally found in extracellular, discharged, and periplasmic proteins, although they can likewise be shaped in cytoplasmic proteins under states of oxidative pressure.

Ionic holding is the finished exchange of valence electron(s) between molecules. In ionic bonds, the metal loses electrons to turn into a decidedly charged cation, while the nonmetal acknowledges those electrons to turn into a contrarily charged anion.

Hydrophobic communications portray the relations among water and hydrophobes (low water-dissolvable atoms). Hydrophobes are nonpolar particles and ordinarily have a long chain of carbons that do not connect with water atoms. The blending of fat and water is a genuine case of this specific connection.

Note: Two hydrogen-bonded helical structures for a polypeptide chain have been found in which the deposits are stereo-chemically identical, the interatomic separations and bond edges have values found in amino acids, peptides, and other straightforward substances identified with proteins, and the formed amide framework is planar.