BCH210H1 Lecture Notes - Lecture 5: 2-Mercaptoethanol, Ultimate Tensile Strength, Globular Protein

• School: UTSG
• Department: Biochemistry
• Course: BCH210H1
• Professor: Stavroula Andreopoulos

Document Summary

Mechanism stable formation of a protein is complex. Levinthal"s paradox many conformations are possible for a typical protein that there is not sufficient time for the sampling of all conformations secondary structures (helices, sheets, turns) form first. Hypothesize that proteins must fold by specific folding pathways. Nonpolar residues aggregate hydrophobic collapse formation of long range interactions between secondary structures or other hydrophobic interactions are subsequent. Process of folding may involve one or more intermediate states transition states known as molten globules. Polypeptides fall down the wall of the funnel as contacts between residues establish different folding possibilities; narrowing funnel represents smaller number of available states as the protein approaches its final state. Bumps/pockets in funnel walls represent partially stable intermediates of the folding pathway. Bottom of the funnel most stable/native folded state of a protein. Tertiary structure typical folded protein is marginally stable. Marginal stability is important for flexibility and motion.