Double-duplication evolution
In the 1 September Science Lang et al. argue that two single-domain biosynthetic enzymes appear to have evolved from gene duplication, followed by fusion, followed by a second gene duplication (Science 2000, 289:1546-1550). Both of the proteins, HisA and HisF, can be broken down into two half beta/alpha barrels. The four half barrels can be superimposed on each other, revealing 22% identical or similar residues. As both enzymes bind biphosphate substrates, each half barrel has a phosphate-bindin
Sep 5, 2000
In the 1 September