Question

Levels of Protein Structure

Enzymes are_____________________ functioning as ________________________.    If digested by something like typsin (a digestive enzyme!), their ______________________structure is lost. If denatured, they will also lose activity, so ____________________, ______________________, and ___________________ structure is also important for proper functioning.

Answer 1

Ans. Enzymes are proteins functioning as biocatalyst.

If digested by something like trypsin (a digestive enzyme), their primary structure is lost. If denatured, they will lose activity, so secondary, tertiary and quaternary structure is also important for proper functioning.

Explanation: Enzymes are defined as biocatalysts of the living system. They are generally protein, a few are RNA, too.

The linear sequence of amino acids in a polypeptide chain is called its primary structure. Due to hydrolytic cleavage by a protease (here, trypsin), the linear amino acid sequence is cleaved into several fragments, thus causing loss of primary structure of the protein.

Primary structure further organizes into secondary and tertiary structures. The association of two or more polypeptide chains is called the quaternary structure of the protein. The higher order of protein structures (secondary, tertiary and quaternary) are stabilized by hydrophobic interactions, H-bonds, disulfide bond (if any), etc. All these structural levels are crucial for the biological functional of the protein. Loss of any structural organization leads to protein denaturation and loss of biological activity, including catalytic activity of enzymes.