CHED 1589 |
| The potential diversity of protein ‘sequence space' is enormous. Even for a 100-residue protein, the number of possible sequences (20**100) is so large that a collection containing one molecule of each protein would fill a volume larger than Avogadro's number of universes. The subset of this sequence space that has actually been sampled by biological evolution represents only a miniscule fraction of this potential diversity. Combinatorial libraries of novel amino acid sequences can provide a rich source of diversity for the discovery of new proteins with useful activities. Randomly generated sequences, however, rarely fold into ordered protein-like structures. To enhance the quality of a library, diversity must be focused into regions of sequence space that favor well-folded structures. We use rational design to produce focused libraries of proteins. Recent experimental work demonstrates that de novo proteins from such libraries – which have neither been selected by evolution, nor designed by computer – fold into native-like structures and display a range of functions. Examples will be presented describing libraries of alpha-helical and beta-sheet proteins. These libraries include well-ordered structures, cofactor binding proteins, catalytically active enzymes, and protein-based biomaterials. |
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Exploring and Exploiting Nature with Biomimetics
8:30 AM-11:45 AM, Tuesday, March 27, 2007 McCormick Place North -- Room N230A, Level 2, Oral
Division of Chemical Education |