Question

What are the primary secondary and tertiary structures of proteins?

Answer 1

The different levels of protein structure are known as primary, secondary, tertiary, and quaternary structure. The primary structure is the sequence of amino acids that make up a polypeptide chain. ... The exact order of the amino acids in a specific protein is the primary sequence for that protein.

Answer 2

Answer:

1. Primary structure of proteins: Refers to sequence amino acids linked together through peptide bonds in a polypeptide chain. It also refers to position of disulphide bonds (-S-S) that are formed between the -SH groups of cysteine residues that are adjacent in space but not in the linear sequence of amino acids.
2. Secondary structure of proteins: The polypeptide chain undergoes regular folding or coiling to give rise secondary structure of protein. The coiling of polypeptide chain is produced and stabilized by weak, low energy non-covalent hydrogen bonds and covalent disulpide bonds. Each hydrogen bond is weak, but collectively hydrogen bonds are strong enough to stabilize the secondary structure. The two most prominent types of secondary structure of proteins are (i) alpha-Helix & (ii) beta-Pleated sheet.
3. Tertiary structure of proteins: Refers to overall three-dimensional structure (native conformation) of a protein molecule. The tertiary structure is derived by further folding and super-folding of polypeptide chain(s) exhibiting secondary structure. The tertiary structure is stabilized by covalent disulfide bonds and various weak non-covalent bonds (hydrophobic interactions/van der Waal forces, ionic interactions and hydrogen bonding).