A guiding principle in the field of protein folding
, Anfinsen's Dogma
states that any protein's final three-dimensional configuration
is predetermined by its constituents. Or in other words, a protein's folded structure is completely inherent to its amino acid
sequence, and needs no outside information or help. This means that the protein molecule
's lowest energy state -- that which it seeks when it begins folding -- is also its native conformation
. A specific instance of this action (in bovine ribonuclease
) was demonstrated experimentally by Christian B. Anfinsen in the mid 1950's, and won him the 1972 Nobel Prize
Chaperone enzymes were once thought to be an exception to Anfinsen's Dogma -- since their job is to surround an unfolded protein until it folds, science had the idea that it was encouraging the protein to fold a certain way. It turns out that chaperone molecules are actually to protect the protein while it is folding, and do nothing to actually influence the final native conformation. Like the bundle of cords underneath your computer, if not organized in some way long straight strands of anything tend to get tangled up when left alone, including proteins. Thus, one of the purposes of chaperone enzymes is to buffer each protein from it's neighbors so they can't become tangled. A secondary purpose is to protect the folding protein from heat stress that may cause it to fold into an ineffective or otherwise dangerous conformation.
Anfinsen's Dogma seems to suggest that since a given set of amino acids hooked together with peptide bonds (that's what a protein is) is going to fold a certain way every time, it should be possible to predict how they are going to fold. If this were true, it would be wonderful for Genetics, as you would be able to determine what a protein looked like and thus what its function was without having to culture the protein. However, much like Computer Science's traveling salesman problem, determining each individual atom's movement with respect to thousands of other individual atoms is an NP-Hard problem. That is to say, since each state is partially determined by each other state, computing all of the possible states would take a nearly infinite amount of time. This finding is known as Levinthal's Paradox, and there is more information about it under that node.