BIOL 1F90 Lecture Notes - Lecture 9: Christian B. Anfinsen, Ribonuclease, Motor Protein
27 Sep 2017
School
Department
Course
Professor
Document Summary
Defined regions of proteins with distinct structures and functions: fold independently of the rest of the protein. These particular amino acid sequences have been duplicated during evolution: the same domain may be found in several different proteins. When the same domain is found in different proteins it has the same characteristic three- dimensional shape, chemical properties, and function. Prior to the 1960s, the mechanisms by which proteins assume their three-dimensional structures were not understood. Christian anfinsen postulated that proteins contain all the information necessary to fold into their proper conformation without the need for organelles or cellular factors: determined by the protein sequence. He hypothesized that proteins spontaneously assume their most stable conformation based on the laws of chemistry and physics. Using purified ribonuclease, found that: chemicals that disrupt bonds cause the enzyme to lose function, removal of those chemicals restored function. Therefore, in the complete absence of any cellular factors, an unfolded protein can refold into its functional structure.
