BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Insulin is a protein composed of two chains, an A chain (with 21 amino acids) and a B chain (with 30 amino acids), which are linked together by sulfur atoms. Insulin is derived from a 74-amino-acid prohormone molecule called proinsulin.

Detailed explanation-2: -Insulin is a small protein, but contains almost all structural features typical of proteins: -helix, -sheet, -turn, high order assembly, allosteric T®R-transition, and conformational changes in amyloidal fibrillation.

Detailed explanation-3: -Insulin is a small globular protein containing two chains, A (21 residues) and B (30 residues) (Fig. 2.1A). Stored in the cell as a Zn2+-stabilized hexamer, the hormone dissociates in the bloodstream to function as a Zn2+-free monomer (Fig. 2.1B).

Detailed explanation-4: -Insulin (, from Latin insula, ‘island’) is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the INS gene. It is considered to be the main anabolic hormone of the body.

Detailed explanation-5: -Hence, insulin is a quaternary structure.