Protein> Going Deeper:

Going Deeper:  Cyrus Levinthal asked how many conformations or possible structures were accessible to a protein and did a protein sample all possible conformations when folding into its correct conformation.  If each amino acid residue has 3 possible conformations that it can access, then a 100 amino acid residue protein would sample 3100 or 1030 possible conformations.  If the time to convert from one conformation to another were very fast, such as 10-13 s, then it would take on average 1027s or 1020 years to sample all possible conformations!  In actuality, proteins have been observed to fold in 10-1 to 103 s either in a cell or in the 'test tube.'   How a protein finds its optimal conformation in this relatively short period of time is known as the Levinthal paradox and lies at the heart of the protein folding problem.

Experiment for Kids
**Sticky Icky** 
play with glue and borax to demonstrate principles of polymerization and crosslinkers

from the menu, choose Experiment Guide, Sticky Icky