Back to the Future
Dean, an associate professor of Ecology, Evolution and Behavior, has described his role as one of finding a way to make the study of historical adaptation an "experimental science." And his experiments with the group of bacterial enzymes known collectively as isopropylmalate dehydrogenase (IDH) have been cited as an example of transformative research that is advancing the field of evolutionary biology.
"The approach I use places a strong emphasis on the relations between protein structure and protein function rather than on the genic analyses that comprise much of the field," he says.
Dean and his colleagues have specifically studied the way Escherichia coli bacteria use IDH to extract energy from different sources. Early bacterial IDHs utilized the co-enzyme or helper molecule nicotinamide adenine dinucleotide (NAD) in this energy metabolism. But at some point in time some bacteria, including E. coli, began using an alternate co-enzyme known as nicotinamide adenine dinucleotide phosphate (NADP), which provides reducing power for biosynthesis. Dean wanted to find out why. By strategically switching six amino acids in IDH that bind NADP, he and his colleagues were able to re-create the enzyme function as it existed roughly 3 billion years ago.
DEAN HOME PAGE
Click here to visit Antony Dean's Home Page
