BIO206H5 Lecture Notes - Lecture 4: Peptide Bond, Protein Folding, Hydrogen Bond
Document Summary
Tertiary and quaternary structure: cumulative effect of many weak bonds, hydrogen bonding. Ionic bonds: van der waals forces (from dipoles, hydrophobic interactions, sometimes covalent disulfide bonds. Ionic bonds: van der waals attractions, hydrogen bonds. Disulfide bonds can form or dissolve depending on the environment in which the protein is in. Sometimes proteins need help to fold correctly into the lowest energy configuration: chaperones can also refold denatured or incorrectly folded proteins, folding requires a lot of. Atp: sometimes chaperones fold i(cid:374)(cid:272)orre(cid:272)tl(cid:455), (cid:271)ut it"s rare. Importance of folding: loss of function, disease (e. g. mad cow, scarpie, entire protein-foldi(cid:374)g (cid:374)et(cid:449)ork has e(cid:448)ol(cid:448)ed to fa(cid:272)ilitate a(cid:374)d/or (cid:272)atal(cid:455)ze the (cid:862)proper(cid:863) folding of proteins: molecular chaperones (which are proteins themselves) Secondary structure the heli(cid:454: right-handed, stabilized by hydrogen bonds between. Secondary structure the sheet: adjacent chains held together by hydrogen bonds between backbone residues, parallel: the chains run in the same direction, n c or c n.